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Competing Contingencies for Escape Behavior

Permanent Link: http://ufdc.ufl.edu/UFE0024848/00001

Material Information

Title: Competing Contingencies for Escape Behavior Effects of Negative Reinforcement Magnitude and Quality
Physical Description: 1 online resource (63 p.)
Language: english
Creator: Hammond, Jennifer
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2009

Subjects

Subjects / Keywords: analysis, behavior, blocking, competing, contingencies, extinction, functional, negative, parameters, problem, reinforcement, response
Psychology -- Dissertations, Academic -- UF
Genre: Psychology thesis, Ph.D.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: Previous research has shown that problem behavior maintained by social-negative reinforcement can be treated without escape extinction by enhancing the quality of positive reinforcement for an appropriate alternative response such as compliance. By contrast, negative reinforcement (escape) for compliance generally has been ineffective in the absence of extinction. It is possible, however, that escape for compliance might be effective if the magnitude or quality of negative reinforcement for compliance is greater than that for problem behavior. This study examined the effects of negative reinforcement magnitude and quality on problem behavior and compliance that occurred in the context of demands. In Study 1, we evaluated the effects of negative reinforcement magnitude on the escape-maintained behavior of 7 individuals with developmental disabilities. Across all treatment phases, compliance produced escape of an equal, greater, or (in some cases) lesser duration than problem behavior. Problem behavior decreased for 2 of 7 subjects when equal magnitudes of reinforcement were delivered for both response options. One subject demonstrated reductions in problem behavior and improvements in compliance in the absence of escape extinction when compliance was positively reinforced. The remaining 4 subjects, however, showed no improvement until extinction was added as a treatment component. In Study 2, we evaluated the effects of negative reinforcement quality on the escape-maintained behavior of 3 individuals by blocking problem behavior for the duration of its occurrence during the escape interval. Treatment effects were achieved for 2 of 3 subjects when the quality of negative reinforcement was manipulated. Enhancing the quality of positive reinforcement for compliance was required for the remaining subject. Taken together, results suggest that (a) very small breaks following problem behavior may be sufficient to maintain behavior that is sensitive to escape as a reinforcer, but that (b) reducing the quality of negative reinforcement for problem behavior via blocking may be effective even though task demands are removed for a period of time.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Jennifer Hammond.
Thesis: Thesis (Ph.D.)--University of Florida, 2009.
Local: Adviser: Iwata, Brian.
Electronic Access: RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2010-08-31

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2009
System ID: UFE0024848:00001

Permanent Link: http://ufdc.ufl.edu/UFE0024848/00001

Material Information

Title: Competing Contingencies for Escape Behavior Effects of Negative Reinforcement Magnitude and Quality
Physical Description: 1 online resource (63 p.)
Language: english
Creator: Hammond, Jennifer
Publisher: University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2009

Subjects

Subjects / Keywords: analysis, behavior, blocking, competing, contingencies, extinction, functional, negative, parameters, problem, reinforcement, response
Psychology -- Dissertations, Academic -- UF
Genre: Psychology thesis, Ph.D.
bibliography   ( marcgt )
theses   ( marcgt )
government publication (state, provincial, terriorial, dependent)   ( marcgt )
born-digital   ( sobekcm )
Electronic Thesis or Dissertation

Notes

Abstract: Previous research has shown that problem behavior maintained by social-negative reinforcement can be treated without escape extinction by enhancing the quality of positive reinforcement for an appropriate alternative response such as compliance. By contrast, negative reinforcement (escape) for compliance generally has been ineffective in the absence of extinction. It is possible, however, that escape for compliance might be effective if the magnitude or quality of negative reinforcement for compliance is greater than that for problem behavior. This study examined the effects of negative reinforcement magnitude and quality on problem behavior and compliance that occurred in the context of demands. In Study 1, we evaluated the effects of negative reinforcement magnitude on the escape-maintained behavior of 7 individuals with developmental disabilities. Across all treatment phases, compliance produced escape of an equal, greater, or (in some cases) lesser duration than problem behavior. Problem behavior decreased for 2 of 7 subjects when equal magnitudes of reinforcement were delivered for both response options. One subject demonstrated reductions in problem behavior and improvements in compliance in the absence of escape extinction when compliance was positively reinforced. The remaining 4 subjects, however, showed no improvement until extinction was added as a treatment component. In Study 2, we evaluated the effects of negative reinforcement quality on the escape-maintained behavior of 3 individuals by blocking problem behavior for the duration of its occurrence during the escape interval. Treatment effects were achieved for 2 of 3 subjects when the quality of negative reinforcement was manipulated. Enhancing the quality of positive reinforcement for compliance was required for the remaining subject. Taken together, results suggest that (a) very small breaks following problem behavior may be sufficient to maintain behavior that is sensitive to escape as a reinforcer, but that (b) reducing the quality of negative reinforcement for problem behavior via blocking may be effective even though task demands are removed for a period of time.
General Note: In the series University of Florida Digital Collections.
General Note: Includes vita.
Bibliography: Includes bibliographical references.
Source of Description: Description based on online resource; title from PDF title page.
Source of Description: This bibliographic record is available under the Creative Commons CC0 public domain dedication. The University of Florida Libraries, as creator of this bibliographic record, has waived all rights to it worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law.
Statement of Responsibility: by Jennifer Hammond.
Thesis: Thesis (Ph.D.)--University of Florida, 2009.
Local: Adviser: Iwata, Brian.
Electronic Access: RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2010-08-31

Record Information

Source Institution: UFRGP
Rights Management: Applicable rights reserved.
Classification: lcc - LD1780 2009
System ID: UFE0024848:00001


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COMPETING CONTINGENCIES FOR ESCAPE BEHAVIOR: EFFECTS OF NEGATIVE
REINFORCEMENT MAGNITUDE AND QUALITY




















By

JENNIFER L. HAMMOND


A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE DEGREE OF
DOCTOR OF PHILOSOPHY

UNIVERSITY OF FLORIDA

2009


































2009 Jennifer L. Hammond

































To my family Mom, Dad, and Stephanie









ACKNOWLEDGMENTS

I thank Sarah Bloom, Carrie Dempsey, and Jenn Fritz for their thoughtful comments and

suggestions throughout the course of the study, as well as Tara Fahmie, Jill Harper, Natalie

Rolider, and Anne Shroyer for their assistance with overseeing subjects. I also extend my sincere

appreciation to Stephen Smith, Donald Stehouwer, and Timothy Vollmer for their guidance and

helpful suggestions on this project. Most of all, I offer my utmost gratitude and admiration to

Brian Iwata for all of the time, commitment, and endless support he provided to this project and

to me throughout my career. I consider myself extremely fortunate to have had such a fine model

and mentor; I am forever grateful.









TABLE OF CONTENTS

page

A C K N O W L E D G M E N T S ..............................................................................................................4

L IST O F T A B L E S ........................................................................................... . 7

LIST OF FIGURES .................................. .. ..... ..... ................. .8

L IST O F A B B R E V IA T IO N S ......... ..........................................................................9

A B S T R A C T ......... ....................... ............................................................ 10

CHAPTER

1 IN TR OD U CTION .......................................................................... .. ... .... 12

Functional Analysis of Problem Behavior ...................................................... ............. 12
Function-Based Treatment Selection .................................................... ... ............13
Treatment of Problem Behavior Maintained by Escape ............. ........................................ 14
Noncontingent Reinforcement................................. .................................... 14
E x tin ctio n ............................................................................... 15
D differential R einforcem ent............................................ ....................................... 16
Treatm ent W ith Escape Extinction .................................................... ............... 17
Treatments Without Escape Extinction............... .................. ................... 18

2 FUNCTIONAL ANALYSIS OF PROBLEM BEHAVIOR .............. ............... 22

M e th o d .............................................................................................................................. 2 2
Subjects and Setting .............................. ............. ...... .. ......... .............. 22
Response Measurement and Reliability .............................................................. 22
P ro c e d u re s .......................................................................................................................2 4
R e su lts ....................... .................... .. ....26..........

3 STUDY 1: EFFECTS OF NEGATIVE REINFORCEMENT MAGNITUDE ......................28

M e th o d .............................................................................................................................. 2 8
Subjects and Setting .............................. ............. ...... .. ......... .............. 28
Response Measurement and Reliability .............................................................. 28
P ro c e d u re s .......................................................................................................................2 9
Experim mental D design ................. ...... ........................ ...... ........ .............. 30
R esu lts ................... ................... .......................................................... .. 3 1









4 STUDY 2: EFFECTS OF NEGATIVE REINFORCEMENT QUALITY.............................37

M e th o d ................................ .............................................................................................. 3 7
Subjects and Setting .............................. ........... ....... ........... ..........37
Response Measurement and Reliability .............................................................. 37
P ro c e d u re s .......................................................................................................................3 9
Experim mental D design .................................... .. .... ..... .. ............40
R e su lts ................... ...................4...................0..........

5 D IS C U S S IO N ........................................................................................................4 3

L IST O F R E F E R E N C E S ..................................................................................... ....................57

B IO G R A PH IC A L SK E T C H .......................................................................... ........................63








































6









LIST OF TABLES


Table page

2 -1 Subject ch aracteristics......................... ................................................. ........................53

3-1 Task demands included for each subject in Study 1 ..... ...........................................54

3-2 Means and ranges of dependent measures for each subject Study 1 ..............................55

4-1 Task demands included for each subject in Study 2................................................56

4-2 Means and ranges of dependent measures for each subject Study 2 ..............................56









LIST OF FIGURES


Figure paMe

2-1 Functional analysis results for Emma, Braxton, Tim, Gary, John, Rita, Keith, Ethan,
and K endra. ................................................................................27

3-1 Treatment results for Emma and Braxton in Study 1. ...................................................... 34

3-2 Treatm ent results for Tim in Study 1.......................................... ........................... 35

3-3 Treatment results for Gary, John, Rita, and Keith in Study 1.........................................36

4-1 Treatment results for Ethan, Keith, and Kendra in Study 2 ............... ...... .............. 42









LIST OF ABBREVIATIONS

FA Functional analysis

SIB Self-injurious behavior

EO Establishing operation

NCR Noncontingent reinforcement

NCE Noncontingent escape

EXT Extinction

DRA Differential reinforcement of alternative behavior

DRO Differential reinforcement of other behavior

DNRA Differential negative reinforcement of alternative behavior

DNRO Differential negative reinforcement of other behavior

HP High preferred

RPM Responses per minute

Sr- Negative reinforcement

Sr+ Positive reinforcement

BL Baseline

PD Property destruction

Mag Magnitude

LQ Low quality

MR Mental retardation









Abstract of Dissertation Presented to the Graduate School
of the University of Florida in Partial Fulfillment of the
Requirements for the Degree of Doctor of Philosophy

COMPETING CONTINGENCIES FOR ESCAPE BEHAVIOR: EFFECTS OF NEGATIVE
REINFORCEMENT MAGNITUDE AND QUALITY

By

Jennifer L. Hammond

August 2009

Chair: Brian A. Iwata
Major: Psychology

Previous research has shown that problem behavior maintained by social-negative

reinforcement can be treated without escape extinction by enhancing the quality of positive

reinforcement for an appropriate alternative response such as compliance. By contrast, negative

reinforcement (escape) for compliance generally has been ineffective in the absence of

extinction. It is possible, however, that escape for compliance might be effective if the

magnitude or quality of negative reinforcement for compliance is greater than that for problem

behavior. This study examined the effects of negative reinforcement magnitude and quality on

problem behavior and compliance that occurred in the context of demands. In Study 1, we

evaluated the effects of negative reinforcement magnitude on the escape-maintained behavior of

7 individuals with developmental disabilities. Across all treatment phases, compliance produced

escape of an equal, greater, or (in some cases) lesser duration than problem behavior. Problem

behavior decreased for 2 of 7 subjects when equal magnitudes of reinforcement were delivered

for both response options. One subject demonstrated reductions in problem behavior and

improvements in compliance in the absence of escape extinction when compliance was

positively reinforced. The remaining 4 subjects, however, showed no improvement until

extinction was added as a treatment component. In Study 2, we evaluated the effects of negative









reinforcement quality on the escape-maintained behavior of 3 individuals by blocking problem

behavior for the duration of its occurrence during the escape interval. Treatment effects were

achieved for 2 of 3 subjects when the quality of negative reinforcement was manipulated.

Enhancing the quality of positive reinforcement for compliance was required for the remaining

subject. Taken together, results suggest that (a) very small breaks following problem behavior

may be sufficient to maintain behavior that is sensitive to escape as a reinforcer, but that (b)

reducing the quality of negative reinforcement for problem behavior via blocking may be

effective even though task demands are removed for a period of time.









CHAPTER 1
INTRODUCTION

Functional Analysis of Problem Behavior

Functional analysis methodology is the benchmark standard for assessment in applied

behavior analysis (cf. Hanley, Iwata, & McCord, 2003; Iwata, Kahng, Wallace, & Lindberg,

2000). This experimental approach identifies environmental variables that maintain problem

behavior through the systematic manipulation of antecedent and consequent events that are

known to influence behavior. Thus, a functional analysis aims to recreate the conditions under

which problem behavior is likely to occur. This series of studies focuses on the functional

analysis and treatment of problem behavior that occurs in the context of instructional demands.

Iwata, Dorsey, Slifer, Bauman, and Richman (1982/1994) were the first to demonstrate the

utility of functional analysis (FA) methodology in elucidating both the social and nonsocial

sources of reinforcement that may maintain problem behavior exhibited by individuals with

developmental disabilities. They created a series of three test conditions and one control

condition, which were alternated rapidly in a multielement design. The test conditions included:

alone (the subject was in a barren environment, and no programmed consequences were placed

on problem behavior; this condition tested for maintenance by automatic reinforcement), social

disapproval (no attention was provided to the subject except contingent on problem behavior;

this condition tested for maintenance by social-positive reinforcement), and academic demand

(instructions were presented on a fixed-time schedule and were removed contingent on problem

behavior only; this condition tested for maintenance by social-negative reinforcement). A play

condition served as the control, in which the subject had noncontingent access to preferred items

and social interaction; the purpose of this condition was to nullify test components of the other

conditions. Differential responding in one or more test conditions indicated the source of









reinforcement that maintained problem behavior, and Iwata et al. demonstrated that the self-

injurious behavior (SIB) of 6 of 9 subjects was reliably associated with a specific stimulus

condition, thus, empirically supporting early hypotheses (e.g., Carr, 1977; Smolev, 1971) that

such problem behavior could be maintained by operant contingencies.

Function-Based Treatment Selection

Although Iwata et al. (1982/1994) noted the implications of their findings for assessment

and treatment, the full scope of FA methodology has become more apparent in the years since its

original publication. The procedures have been replicated in hundreds of studies across various

populations, settings, and topographies of problem behavior (see Hanley et al., 2003, for a

discussion). Furthermore, the use of FA methodology has been cited as a prime factor

contributing to a decrease in the use of punishment (Pelios, Morren, Tesch, & Axelrod, 1999),

government regulations specifying "best practice" (e.g., Individuals with Disabilities Educational

Act; IDEA, 1997), and the development of more effective treatments overall.

Perhaps the most pragmatic feature of FA methodology is that it can be used to guide the

selection of treatments based on principles of reinforcement to yield the most efficient and

effective outcomes. Prior to the use of FA methodology, reinforcement-based interventions often

were applied haphazardly based on one's best guess as to what approach might prove most

effective. Because the success of such arbitrary approaches to treatment selection often hinged

on the ability of the programmed reinforcer to compete with the behavior's maintaining

contingency, these early attempts at treatment sometimes failed or were less effective than

procedures based on punishment (e.g., Cataldo, 1991).

A number of function-based treatments that center on principles of reinforcement have

been identified over the past 20 years (cf. Iwata, Vollmer, Zarcone, & Rodgers, 1993). These

procedures are best classified according to their underlying behavioral processes. Problem









behavior can be suppressed through: (a) eliminating the relevant establishing operation or EO

that influences the "value" of a reinforcer noncontingentt reinforcement), (b) eliminating the

maintaining contingency (extinction), and (c) strengthening a competing response (differential

reinforcement). These general strategies are common across problem behavior, although

procedural differences arise based on the source of reinforcement that maintains a particular

behavior.

Treatment of Problem Behavior Maintained by Escape

Social-negative reinforcement plays a prominent role in the maintenance of problem

behavior (cf. Iwata, 1987). Epidemiological studies indicate that avoidance of or escape from

task demands may account for the largest proportion of problem behavior shown by individuals

with developmental disabilities roughly 40% (Derby et al., 1992; Iwata et al., 1994b).

Therefore, an understanding of the role that negative reinforcement plays in the development and

maintenance of problem behavior is important to the development of effective treatment.

A number of reinforcement-based treatments for escape-maintained behavior have been

developed over the years (see Cipani & Spooner, 1997, for a review). These procedures are best

classified according to the three fundamental approaches noted previously, namely:

noncontingent reinforcement (EO manipulations), extinction, and differential reinforcement.

Noncontingent Reinforcement

Noncontingent reinforcement (NCR) decreases behavior by eliminating the EOs that make

behavior reinforcing in the first place. In typical application, NCR involves the delivery of the

consequence that is responsible for behavioral maintenance according to a time-based schedule

(see Carr et al., 2000, for a review). For problem behavior maintained by negative reinforcement,

this may mean that escape (a break from work) is delivered frequently in a demand context,

irrespective of the subject's behavior (NCE; e.g., Vollmer, Marcus, & Ringdahl, 1995).









Alternatively, noncontingent access topositive reinforcers during instructional trials also has

been used to treat escape-maintained behavior. For example, Wilder, Normand, and Atwell

(2005) found that 1 subject's self-injury and food refusal decreased when she was given

noncontingent access to preferred videos during feeding sessions. Another antecedent

intervention that has been shown to reduce problem behavior maintained by escape is stimulus

fading, in which the difficulty (e.g., Weeks & Gaylord-Ross, 1981) or frequency (e.g., Pace,

Iwata, Cowdery, Andree, & McIntyre, 1993; Pace, Ivancic, & Jefferson, 1994) of the task

initially is reduced to the point where problem behavior no longer is evoked, and then gradually

increased to baseline levels while low rates of problem behavior are maintained. Finally, the

high-probability instructional sequence or "high-p sequence" involves presenting a series of

instructions with which the subject is likely to comply immediately before an instruction with

which the subject is not likely to comply the "momentum" of compliance generated by the

high-p responses is believed to facilitate response persistence in the face of changing conditions

(i.e., low-p demands) (e.g., Mace & Belfiore, 1990). The common feature among all of these

procedures is the alteration of an antecedent event that typically evokes problem behavior.

Extinction

Extinction (EXT) suppresses behavior by discontinuing the response-reinforcer

relationship (Ferster & Skinner, 1957). Identification of the behavior's maintaining contingency,

therefore, is a prerequisite for the effective use of EXT (Iwata, Pace, Cowdery, & Miltenberger,

1994a). For problem behavior maintained by negative reinforcement, EXT involves continued

presentation of demands and prevention of escape contingent on the occurrence of problem

behavior (Iwata, Pace, Kalsher, Cowdery, & Cataldo, 1990). Iwata et al. (1990) found that the

escape-maintained SIB of 5 of 6 individuals with developmental disabilities rapidly decreased

when problem behavior no longer produced a break, and also observed concomitant









improvements in the subjects' compliance even though the contingencies for compliance

remained unchanged. These effects have been replicated in numerous studies, and escape EXT

may well be regarded as the most effective and efficient method of decreasing problem behavior

that occurs in the context of demands (cf. Iwata, 1987). In short, it is a key component of many

behavioral procedures (e.g., NCR, differential reinforcement, as well as punishment), and the

effectiveness of these procedures may be a function solely of EXT (see Lerman & Iwata, 1996b,

for a review).

Differential Reinforcement

Differential reinforcement, including differential reinforcement of alternative behavior

(DRA) and differential reinforcement of other behavior (DRO), suppresses problem behavior by

strengthening a competing response or some feature of a response, such as longer inter-response

times in the case of DRO (see Vollmer, 1999, for a discussion). Differential reinforcement for

escape-maintained behavior may take one of several forms. First, negative reinforcement may be

delivered contingent on an appropriate alternative response (DNRA). For example, escape from

task demands for a period of time may be delivered contingent upon a request for a break (e.g.,

"finished"; Marcus & Vollmer, 1995); similarly, aversive characteristics of the task may be

reduced contingent on an appropriate request for assistance (e.g., "help"; Carr & Durand, 1985).

Alternatively, escape may be provided contingent on compliance (Marcus & Vollmer). By

contrast, DRA for escape-maintained behavior may include delivering potent positive reinforcers

(e.g., preferred edible items or toys) contingent on an appropriate alternative response, such as

compliance (DeLeon, Neidert, Anders, & Rodriguez-Catter, 2001; Lalli et al., 1999; Piazza et al.,

1997). Finally, differential negative reinforcement of other behavior (DNRO) involves providing

escape from task demands contingent on the omission of problem behavior for a period of time

(e.g., Kodak, Miltenberger, & Romaniuk, 2003; Vollmer et al., 1995). Collectively, results of









these studies have shown that, when reinforcement is delivered contingent on some characteristic

of behavior other than the target problem behavior, a decrease in that problem behavior typically

is observed (see Vollmer & Iwata, 1992, for a general review of differential reinforcement

procedures). It is important to note that differential reinforcement almost always includes an

EXT component, which eliminates the possibility that problem behavior might compete with

alternative behavior.

Treatment With Escape Extinction

Although the interventions described above have been found to be extremely effective in

treating behavior that occurs in the context of demands, most share one common element that

may be partially or wholly responsible for observed treatment effects namely, the use of EXT.

Most research has shown that EXT is a critical component of treatment (Mazaleski, Iwata,

Vollmer, Zarcone, & Smith, 1993; Zarcone, Iwata, Hughes, & Vollmer, 1993; Zarcone, Iwata,

Mazaleski, & Smith, 1994; Zarcone, Iwata, Smith, Mazaleski, & Lerman, 1994). For example, in

a series of studies, Zarcone et al. demonstrated that escape EXT contributed to the success of the

high-p instructional sequence and demand fading procedures, and that (in some cases) EXT

alone was sufficient to suppress problem behavior and increase compliance (e.g., Zarcone et al.,

1993).

Despite the fact that EXT is a highly effective treatment, adverse side effects such as

bursting (a temporary increase in responding) or EXT-induced aggression have been observed

occasionally, which may preclude its use in applied settings (Goh & Iwata, 1994; Lerman, Iwata,

& Wallace, 1999). Moreover, the severity of problem behavior or the size of the individual who

exhibits it may prevent the use of EXT for escape-maintained behavior. That is, because EXT

requires the continued presentation of demands and prevention of escape, which also may require

physical intervention, it may not be feasible with large or combative individuals. Thus, an









important treatment consideration is whether it is possible to decrease problem behavior

maintained by escape without EXT.

Treatments Without Escape Extinction

Results of some studies have suggested that antecedent interventions such as demand

fading (Pace et al., 1994) and activity choice (Romaniuk et al., 2002), as well as consequent

interventions such as DRA (Homer & Day, 1991; Lalli, et al., 1999; Piazza et al., 1997), might

be effective even when escape-maintained behavior continues to be negatively reinforced with

greater emphasis being placed on DRA. Although most research on DRA for escape-maintained

behavior has incorporated EXT, several studies have shown that DRA without EXT may be

effective when qualitatively different reinforcers are used. For example, positive reinforcement

for compliance, either alone (e.g., an edible item; DeLeon et al., 2001; Lalli et al.) or combined

with negative reinforcement (e.g., access to preferred activities and/or attention during the escape

interval; Hoch, McComas, Thompson, & Paone, 2002; Lalli & Casey, 1996; McComas,

Goddard, & Hoch, 2002; Piazza et al.) has been shown to reduce escape-maintained behavior

without EXT. Because the contingencies arranged in these studies involved different reinforcers

(i.e., positive reinforcement for compliance versus negative reinforcement for problem behavior),

these arrangements can best be described as unequal or asymmetrical (see Fisher & Mazur, 1997,

for a discussion).

Several studies also have examined whether negative reinforcement (alone) for an

appropriate alternative response may compete with problem behavior maintained by escape in

the absence of EXT. Because the contingencies arranged in these studies involved qualitatively

similar reinforcers (negative reinforcement for both compliance and problem behavior), these

arrangements incorporate equal outcomes. Although the majority of studies have shown

negligible effects when escape for appropriate and problem behavior was equivalent (DeLeon et









al., 2001; Hoch et al., 2002; Lalli et al., 1999), results of some studies have suggested that escape

for an appropriate alternative response may compete with escape for problem behavior. For

example, Piazza et al. (1997) found that the escape-maintained problem behavior of 1 of 3

subjects eventually decreased to zero when both compliance and problem behavior produced

equal durations of negative reinforcement. Similarly, Horner and Day (1991) found that escape

for an appropriate alternative response produced both reductions in problem behavior and

improvements in the alternative response when the alternative response (mand) was either more

efficient or reinforced more frequently than the target response. In general, however,

idiosyncratic results have been obtained in studies evaluating the effects of DNRA on escape-

maintained behavior when equal outcomes are incorporated.

One method that might enhance the effects of negative reinforcement for compliance

would be to increase the magnitude (duration) of escape for appropriate behavior relative to that

for problem behavior. Some applied research has shown that increasing the magnitude of

positive reinforcement may decrease behavior that is maintained by access to tangible items. For

example, Carr, Bailey, Ecott, Lucker, and Weil (1998) obtained lower rates of responding when

a relatively large amount of food was delivered noncontingently (i.e., in the NCR-high

condition), whereas baseline rates of responding were obtained when smaller amounts of food

were delivered in the NCR-low condition. Roscoe, Iwata, and Rand (2003) extended these

findings by showing that larger magnitudes of reinforcement, defined functionally based on rates

of responding during contingent reinforcement, can reduce response rates under NCR even when

session time is corrected to account for reinforcer consumption time. Lerman, Kelley, Van

Camp, and Roane (1999) also showed that DRA + EXT produced consistently lower levels of









problem behavior when a functionally equivalent alternative response resulted in a longer

duration of access to the putative reinforcer (i.e., toys).

Although magnitude has been shown to be a somewhat influential parameter for behavior

maintained by positive reinforcement, the effects of negative reinforcement magnitude are less

certain. Very little applied research has been conducted on the effects of negative reinforcement

magnitude. A notable exception is a study by Lerman, Kelley, Vorndran, Kuhn, and LaRue

(2002), who examined the effects of reinforcement magnitude on the appropriate communication

of 3 subjects whose problem behavior was placed on EXT throughout the evaluation. For

subjects whose problem behavior was maintained (at least in part) by escape from task demands,

the duration of escape delivered contingent on appropriate communication was varied. Results

generally showed that the subjects' rates of communication were similar across the 20-, 60-, and

300-s magnitude conditions, thus suggesting that negative reinforcement magnitude may not be a

major determinant of behavior. It is possible, however, that the single reinforcement schedule for

appropriate behavior, in which only one magnitude was available in a given experimental

condition, partially contributed to the negative results obtained. It has been noted that concurrent

schedules, in which different parameters are compared directly by making both available but for

different responses, are better suited to examine the relative effects of reinforcement magnitude

(cf., Catania, 1963). Additionally, because problem behavior was placed on EXT throughout the

evaluation, the relative effects of negative reinforcement magnitude on problem behavior

maintained by escape remain unknown.

It is also possible that escape-maintained behavior could be treated without EXT by

altering qualitative characteristics of negative reinforcement. Most research on competing

contingencies for behavior has shown that the quality of positive reinforcement is a highly









influential determinant of reinforcement effects (e.g., Kodak et al., 2007; Lalli et al., 1999; Mace,

Neef, Shade, & Mauro, 1996; Neef, Mace, Shea, & Shade, 1992; Neef, Shade, & Miller, 1994).

However, it remains unknown whether negative reinforcement quality would prove to be an

equally powerful parameter. One way its effects could be evaluated would be to block problem

behavior for the duration of its occurrence, which might reduce the quality of reinforcement

because escape is available only to the extent that blocking is in effect. Thus, reductions in

problem behavior might be obtained even though problem behavior continues to produce escape

on some level. This question has direct clinical relevance because the severity of the behavior

(i.e., SIB or aggression) sometimes necessitates immediate intervention to ensure the safety of

the individual or others. Surprisingly, very little research has been conducted in this area. A

notable exception is a study by Peck et al. (1996), who found that the escape-maintained problem

behavior of 2 subjects decreased when problem behavior was blocked; however, because both

the magnitude of negative reinforcement and quality of positive reinforcement associated with

the appropriate alternative response also were enhanced in this study, the effects of blocking per

se on problem behavior maintained by escape remain unknown.

In summary, although the majority of applied research suggests that negative

reinforcement (alone) for compliance is ineffective in reducing escape-maintained problem

behavior without EXT, additional research is warranted. That is, little research been conducted

on methods for strengthening negative reinforcement for appropriate behavior relative to that for

problem behavior. The purpose of this study therefore is to determine whether increases in

compliance and decreases in escape-maintained problem behavior may be obtained when the

magnitude or quality of negative reinforcement for problem behavior is lessened relative to that

for compliance.









CHAPTER 2
FUNCTIONAL ANALYSIS OF PROBLEM BEHAVIOR

Method

Subjects and Setting

Nine individuals diagnosed with developmental disabilities who were referred for

assessment and treatment of problem behavior participated. Subject characteristics are listed in

Table 2-1. Functional analyses were conducted initially as a screening procedure to identify

subjects whose problem behavior was maintained by escape from task demands. Sessions were

conducted in a self-contained classroom at a special education school or in an observation room

at an adult day program. Session areas contained a table and chairs, as well as materials that

varied according to the condition in effect. Setting and room characteristics remained the same

across Studies 1 and 2. Sessions were 10 min in duration; 1 to 5 sessions were conducted each

day, and sessions typically were conducted 2 to 5 days per week depending on the subjects'

schedules.

Response Measurement and Reliability

The primary dependent measure was the number of responses per minute of problem

behavior. Topographies of problem behavior included property destruction (Emma, Tim, John,

and Keith), self-injury (Braxton and Kendra), and aggression (Gary, Rita, and Ethan).

Operational definitions of the target problem behaviors for each subject are listed in Table 2-1.

Data also were collected on the subjects' compliance with demands (Emma, Braxton, Tim, John,

Rita, and Ethan), which was defined as completion of the task following either a verbal or model

prompt.

Several therapist behaviors also were recorded. Attention delivery was defined as the

therapist initiating verbal or physical interaction with the subject. A prompt was defined as the









initial instruction in a three-step sequence. Escape was defined as the therapist terminating

demands and turning away from the subject for 30 s. Tangible was defined as the therapist

handing the subject an item or placing an item directly within reach of the subject.

Observers recorded the frequency of subject target problem behavior, subject compliance,

and therapist behavior during continuous 10-s intervals using a handheld Palm PDA.

Interobserver agreement was assessed by having a second observer simultaneously but

independently collect data during at least 25% of the FA sessions for all subjects. Proportional

agreement percentages were calculated for each response by comparing the two observers'

recorded frequencies during each 10-s interval. The smaller number of responses was divided by

the larger number in each interval with a disagreement, the fractions were summed across all

intervals, and the total was added to the total number of agreement intervals in the session. The

sum was divided by the total number of intervals in the session and multiplied by 100% to yield

reliability scores for each dependent measure. Mean reliability scores were as follows: Emma,

94.5% for property destruction (range, 84.2% to 100%), 96.7% for compliance (range, 93.3% to

100%), and 94.4% for therapist behaviors (range, 90% to 100%); Braxton, 100% for SIB, 100%

for compliance, and 97% for therapist behaviors (range, 89.2% to 100%); Tim, 97.1% for

property destruction (range, 88.5% to 100%), 96.7% for compliance, and 91.7% for therapist

behaviors (range, 80% to 100%); Gary, 99.8% for aggression (range, 99.2% to 100%) and 97.5%

for therapist behaviors (range, 93.3% to 100%); John, 100% for property destruction, 100% for

compliance, and 97% for therapist behaviors (range, 90% to 100%); Rita, 96.1% for aggression

(range, 95% to 100%), 100% for compliance, and 96.9% for therapist behaviors (range, 93.3% to

100%); Keith, 99.5% for property destruction (range, 96.7% to 100%) and 100% for therapist

behaviors; Ethan, 98.5% for aggression (range, 94.2% to 100%), 96.7% for compliance, and









93.5% for therapist behaviors (range, 73.3% to 100%); and Kendra, 100% for SIB and 100% for

therapist behaviors.

Procedures

FAs were conducted using procedures similar to those described by Iwata et al.

(1982/1994). Test and control conditions were alternated in a multielement design. Attention,

play, and demand conditions were included in all FAs. An ignore condition generally was not

included if the target response was aggression, and a tangible condition was conducted only if

caregiver report suggested that problem behavior might be maintained by access to preferred

items or activities. Specific stimuli (e.g., different therapists, session areas, or colored shirts)

were associated with each FA condition to enhance discrimination of the contingencies in effect

(Conners et al., 2000).

Ignore: The purpose of this condition was to determine if problem behavior would persist

in the absence of social contingencies, suggesting that problem behavior was maintained by

nonsocial (automatic) reinforcement. The subject was in an isolated area of the room without

access to leisure items or social interaction. The therapist also was present but did not interact in

any way with the subject throughout the session.

Attention: The purpose of this condition was to determine if problem behavior was

maintained by social-positive reinforcement in the form of attention. The subject had access to 2-

3 moderately preferred toys identified via a paired-stimulus (Fisher et al., 1992) or a multiple-

stimulus (DeLeon & Iwata, 1996) preference assessment. At the start of the session, the therapist

told the subject, "I have some work to do, but you can play with these toys if you'd like." The

therapist sat next to but did not interact with the subject. Contingent upon each occurrence of

target problem behavior, however, the therapist delivered a brief reprimand and statement of









concern (e.g., "You shouldn't do that; you're going to hurt yourself!") and gentle physical

contact (e.g., placed a hand on the subject's arm).

Tangible: The purpose of this condition was to determine if problem behavior was

maintained by social-positive reinforcement in the form of access to preferred items. The subject

was given approximately 60-s access to 3 high-preferred (HP) edible items (identified in a

preference assessment) immediately before the start of the session. At the start of the session, the

therapist removed the items from the subject but remained nearby. If the subject initiated

interaction with the therapist during this condition, the therapist briefly responded to the subject

and then terminated the interaction (e.g., quickly answered a question or said "We'll talk later.").

Contingent on the occurrence of problem behavior, one small edible item was delivered.

Demand: The purpose of this condition was to determine if problem behavior was

maintained by social-negative reinforcement in the form of escape from task demands. The

subject was seated at a table with task materials present. The therapist initiated academic or

vocational trials on a fixed-time 30-s schedule using a graduated, three-step prompt sequence

(verbal instruction, model prompt, physical guidance at 5-s intervals if compliance did not

occur). Contingent on compliance, the therapist delivered verbal praise and began a new trial.

Contingent on problem behavior, the therapist discontinued the demands and moved away from

the subject for 30 s.

Play: This condition served as the control condition in which antecedent and consequent

events likely to occasion problem behavior were absent. The subject and therapist were seated at

a table or on the floor. The subject had continuous access to 2-4 HP leisure items (identified in a

preference assessment), and the therapist initiated friendly interaction with the subject

approximately every 30 s (contingent upon a 5-s absence of problem behavior) or any time the









subject initiated appropriate interaction. No consequences were delivered following the

occurrence of problem behavior.

Results

Figure 2-1 shows results of the FAs for each subject who participated in Studies 1 and 2.

Emma, Braxton, Tim, Gary, John, Rita, and Keith engaged in higher rates of problem behavior in

the demand condition and little or no problem behavior in any other condition, indicating that

their problem behaviors were maintained by escape from task demands.

Ethan and Kendra also engaged in high rates of problem behavior in the demand condition.

However, their problem behavior occurred at somewhat similar rates in the tangible condition.

Thus, Ethan's aggression and Kendra's hand biting appeared to be maintained not only by escape

from task demands but also by access to preferred edible items.

Taken together, data for all subjects indicate that their problem behaviors were maintained

(at least in part) by social-negative reinforcement, which was a prerequisite for participation in

the treatment phases of this study.















8




4


0 -- ----e \
2 ^f^t S" V
pJ>^. a -


5 10 15 20


1.0

0a

0.6

04-

0.2

0.0 ** g .0-. 0


5 10 15


Tim


0 -0
5 10 15


3 to

0.8
2
20.6 /



0.24

0 1 O----. --o-n- ., .a -- 'c I 0--*-
5 10 15 5 10 15 20


3-









5 10 15


5 IS3

4 r-,u1,0 \







20 10 20 30

SESSIONS


e 0----e-


5 10











b 10 .1..........
5 10 15


Figure 2-1. Functional analysis results for all subjects. Emma, Braxton, Tim, Gary, John, Rita,

and Keith participated in Study 1; Keith, Ethan, and Kendra participated in Study 2.









CHAPTER 3
STUDY 1: EFFECTS OF NEGATIVE REINFORCEMENT MAGNITUDE

Method

Subjects and Setting

Emma, Braxton, Tim, Gary, John, Rita, and Keith participated in Study 1. Sessions were

10 min in duration; 1 to 8 sessions were conducted each day, and sessions typically were

conducted 2 to 5 days per week depending on the subjects' schedules.

Response Measurement and Reliability

The primary dependent measure was the number of responses per minute of problem

behavior (see Table 2-1 for definitions). Data also were collected on subjects' compliance with

demands, as previously defined. The demands included for each subject are listed in Table 3-1.

The frequency of therapist behavior, including initial verbal instructions and reinforcer

delivery (i.e., escape and edible item, if applicable) was recorded. Additionally, data were

collected on reinforcer consumption time (the duration of the escape interval), which was

subtracted from session time, yielding a conservative estimate of the rate of problem behavior

that was not artificially suppressed merely as a function of reduced time spent in the presence of

demands.

Interobserver agreement was calculated as previously described. Mean reliability scores

were as follows: Emma, 96.6% for property destruction (range, 86.6% to 100%), 97% for

compliance (range, 93.3% to 100%), 92.2% for therapist instructions (range, 84.2% to 100%),

and 98% for therapist reinforcer delivery (range, 91.6% to 100%); Braxton, 98.9% for SIB

(range, 92.5% to 100%), 98.6% for compliance (range, 90.3% to 100%), 93.4% for therapist

instructions (range, 85% to 100%), and 95.9% for therapist reinforcer delivery (range, 55% to

100%); Tim, 97.7% for property destruction (range, 86.5% to 100%), 96.7% for compliance









(range, 90% to 100%), 97.1% for therapist instructions (range, 87.8% to 100%), and 97% for

therapist reinforcer delivery (range, 86.7% to 100%); Gary, 96.8% aggression (range, 87.5% to

100%), 96.1% for compliance (range, 84.1% to 100%), 93.3% for therapist instructions (range,

79.9% to 100%), and 94.7% for therapist reinforcer delivery (range, 82.5% to 100%); John,

96.1% for property destruction (range, 87.5% to 100%), 98% for compliance (range, 90% to

100%), 91.9% for therapist instructions (range, 68.3% to 100%), and 97.3% for therapist

reinforcer delivery (range, 86.7% to 100%); Rita, 95.6% for aggression (range, 80.6% to 100%),

98.4% for compliance (range, 90% to 100%), 93.3% for therapist instructions (range, 79.2% to

100%), and 97.3% for therapist reinforcer delivery (range, 86.7% to 100%); and Keith, 94.4%

for property destruction (range, 81.7% to 100%), 97% for compliance (range, 79.2% to 100%),

95.7% for therapist instructions (range, 84.2% to 100%), and 96.7% for therapist reinforcer

delivery (range, 89.2% to 100%).

Procedures

A concurrent-schedule arrangement, in which two or more response options are available

to a subject, each associated with a different consequence (Catania, 1963), was used to evaluate

the effects of negative reinforcement magnitude on compliance and on problem behavior. The

magnitude (duration) of escape associated with compliance and/or problem behavior was

systematically manipulated across conditions, such that (a) compliance did or did not produce a

break (or access to positive reinforcement), and (b) problem behavior did or did not produce a

break of equal, lesser, or (in some cases) greater magnitude than compliance. The contingencies

in effect were not described to the subjects at any time. Treatment conditions are labeled with

two symbols (e.g., Praise/ Sr); the first symbol denotes the consequences for compliance, and the

second symbol denotes the consequence for problem behavior.









Baseline (Praise/ Sr): Procedures were similar to the demand condition of the FA.

Compliance resulted in verbal praise followed by resumption of task demands. Problem behavior

produced 30-s escape.

Equal Escape (Sr-/ S-): Procedures were similar to those used in baseline, except that

compliance also produced a 30-s break.

Enhanced Reinforcement Magnitude for Compliance (Enhanced Sr/ Sr): Procedures

will were similar to those used in the equal S-/ Sr- condition, except that compliance now

produced 120-s escape from the task, whereas problem behavior continued to result in 30-s

escape (i.e., 120/ 30). If this phase proved ineffective, the magnitude of reinforcement for

problem behavior was reduced, such that problem behavior produced only 5-s escape (i.e., 120/

5).

Positive Reinforcement for Compliance (S"/ Sr-): Escape no longer was provided for

compliance. Rather, contingent on compliance, one of three HP edible items was delivered in a

varied format (Egel, 1981). Immediately following the delivery of the HP edible item, the

therapist instructed the subject to complete another task. Problem behavior continued to produce

30-s escape.

Positive Reinforcement plus Extinction (S"/ EXT): Procedures were similar to those

used in the previous Sr+/ S- phase, except that extinction (EXT) now was in effect for problem

behavior. Contingent on the occurrence of problem behavior, the therapist physically guided the

subject to complete the task and then presented the next demand; no break was provided.

Experimental Design

Experimental control was established by way of a multiple baseline across subjects (Emma

and Braxton) or reversal designs (Tim, Gary, John, Rita, and Keith). The A condition consisted

of baseline, the B condition consisted of equal Sr-/ S-, the C condition consisted of enhanced









magnitude Sr-/ Sr (i.e., 120/ 30 or 120/ 5), the D condition consisted of Sr/ Sr-, and the E

condition will consisted of Sr+/ EXT. Treatment conditions were implemented sequentially, such

that a given condition was implemented only after the previous condition was found to be

ineffective.

Results

Table 3-2 summarizes means and ranges for subjects' problem behavior and compliance

across baseline and treatment conditions. Figure 3-1 shows results for Emma and Braxton.

Emma exhibited variable rates of property destruction and low levels of compliance during

baseline. When the equal escape (Sr-/ Sr-) condition was implemented, her problem behavior

decreased to near-zero rates, and her compliance increased steadily across this condition.

Braxton engaged in lower rates of problem behavior than did Emma during baseline. His

compliance also was low but increased gradually throughout the condition. Braxton's hand biting

immediately decreased to zero rates when equal Sr-/ Sr- was implemented; however, unlike

Emma, his compliance improved very little. The enhanced reinforcement magnitude condition

(enhanced mag Sr-/ S-) therefore was implemented in an effort to increase his compliance.

However, increasing the relative magnitude of negative reinforcement for compliance from 30/

30 to 120/ 30 was not an effective strategy for Braxton, as his compliance remained relatively

unchanged from the previous condition. Because Braxton typically complied with the same two

demands only (i.e., touch card, hand therapist card), it was concluded that additional teaching

strategies rather than augmented amounts or qualities of reinforcement were necessary to

further increase his compliance with the other tasks selected (i.e., "touch [body part]").

Tim (Figure 3-2) engaged in variable levels of property destruction and compliance during

baseline. The equal Sr-/ S- condition did not produce clinically significant reductions in his

problem behavior, although his compliance did improve. Similar results were obtained in the









subsequent enhanced magnitude Sr-/ Sr conditions (120/ 30 and 120/ 5), as both property

destruction and compliance remained relatively unchanged. When a preferred edible item was

delivered contingent on compliance during the S+/ Sr- condition, his property destruction quickly

decreased and his compliance increased sharply, even though problem behavior continued to be

negatively reinforced. When baseline was reinstated, Tim's problem behavior escalated to the

highest rates obtained throughout the evaluation. When the Sr+/ Sr- condition was reimplemented,

treatment effects were replicated and maintained.

Figure 3-3 shows results for Gary, John, Rita, and Keith. Although slight differences were

seen in their rates of problem behavior and compliance during baseline and across subsequent

conditions, all subjects showed the same general pattern of responding. No significant

improvements were observed in their behavior during either the equal or enhanced magnitude Sr-

/ S- conditions. Similarly, the Sr+/ S- condition had either negligible effects on behavior (Gary,

Rita, and Keith) or beneficial effects on compliance but not on problem behavior (John). When

the Sr/ EXT condition was implemented, large reductions in problem behavior were observed

for all subjects, and improvements in compliance were observed for 3 subjects (Rita was the

exception). Following a return to baseline, these effects were replicated during the final Sr/ EXT

condition.

In summary, 2 of 7 subjects (Emma and Braxton) exhibited reductions in problem

behavior in the equal Sr-/ Sr- condition; however, only 1 subject's (Emma's) compliance

increased. Enhancing the magnitude of negative reinforcement for compliance, relative to that

for problem behavior (enhanced mag Sr-/ Sr- condition), was ineffective for all 6 subjects who

were exposed to this condition. These results suggest that providing a break following problem

behavior no matter how brief- may be sufficient to maintain problem behavior that is sensitive









to escape as a reinforcer as long as compliance also produces escape. Providing a preferred

edible item contingent on compliance while problem behavior continued to produce escape (Sr+/

Sr- condition) was effective for only 1 of 5 subjects in this study. It appeared that, for Tim,

positive reinforcement was a more potent reinforcer than negative reinforcement even though

his problem behavior was maintained by escape. However, because we did not include a tangible

condition in Tim's FA, it remains unknown whether his property destruction also was maintained

by access to preferred items. Finally, escape EXT was required to decrease the remaining 4

subjects' problem behavior. Although not all subjects were exposed to EXT because it was

implemented only if other procedures were ineffective, the fact that a majority of subjects

showed reliable improvements in behavior only when EXT was used were consistent with a great

deal research showing rapid reductions in problem behavior during EXT.












Baseline
(BL) Equal sr/S'
12- 100
PD
Emma
SCompliance 80
8 0
+-60

-40
4-
S* -20 -

0 o- -0 W
S2- sB Enhanced Mag Sr/Sr' -100 Z
Sr |120/30



1-
-40


S-20
0-r!/ A -------- ----- ---
10 20 30 40 50 60

SESSIONS


Figure 3-1. Treatment results for Emma and Braxton in Study 1. (* The asterisk below Emma's
compliance data point in the first equal Sr-/ Sr- session [session #9] indicates that
problem behavior is not plotted; corrected rates could not be calculated due to a
missing data stream.)












S L Equail i/ DtL Dninai iw xU ig a to I a a /
25 1 20130 120/5 V -100

20- 80 -
0 PD
15- Tim e
i I 60

1o- -40 Z

5- -20

0 0" 40 U
10 20 30 40 50 60 70 80 90 100
SESSIONS

Figure 3-2. Treatment results for Tim in Study 1.




















5 10 15 20 25 30 35 40 45 50 55
Enhanced


AGC

n


0
120
U
10 20 30 40 50 60 70 80
Equal Enhanced Mag S-/S8
3L Sr-,S 12030 120/5 I S '/SS/EXT SW/EXT 100
Rita
I 8

I A 1 -- o i A 8


4


10 20 30 40 50 60 70 80 90 100 110


10 20 30 40 50 60 70 80
SESSIONS


Figure 3-3. Treatment results for Gary, John, Rita, and Keith in Study 1.


Ir~n~e~~


,, ~,~


1) 1 ... ..


J I


N


.,~









CHAPTER 4
STUDY 2: EFFECTS OF NEGATIVE REINFORCEMENT QUALITY

Results of Study 1 suggested that enhancing the magnitude of negative reinforcement for

compliance may not be effective when problem behavior continues to produce escape, and that

EXT may be necessary to reduce the problem behavior of most subjects. However, as previously

discussed, it may not always be possible for caregivers to implement EXT for escape-maintained

behavior. Given that reinforcement quality has been found to be an important determinant of

reinforcement effects, it is possible that problem behavior maintained by escape may be treated

by reducing the quality of negative reinforcement available for problem behavior relative to that

for compliance. The purpose of Study 2, therefore, was to examine the effects of negative

reinforcement quality on problem behavior and on compliance when EXT is not used.

Method

Subjects and Setting

Ethan, Keith, and Kendra participated in Study 2. Sessions were 10 min in duration; 1 to 4

sessions were conducted each day, and sessions typically were conducted 2 to 5 days per week

depending on the subjects' schedules.

Response Measurement and Reliability

The primary dependent measure was the number of responses per minute of problem

behavior (see Table 2-1 for definitions). Attempts to engage in the target problem behavior also

were recorded during conditions that included response blocking. Ethan's attempts to engage in

aggression were defined as raising or swinging his hand, arm, or leg in the direction of the

therapist; placing his mouth within 1 inch of the therapist; and rapidly moving his body within 6

inches of the therapist. Keith's attempts to engage in property destruction were defined as

picking up an item and raising his forearm (containing the item) to a 45-degree angle or more,









placing his thumb and one or more fingers at the top of a sheet of paper in such a manner that the

paper could tear if he rotated his fingers in opposite directions, reaching his hand within 6 inches

of a wall containing paper, or swinging his hand or arm within 6 inches of an item (e.g.,

furniture) in a rapid and forward motion. Kendra's attempts to engage in SIB were defined as

placing her mouth within 6 inches of her palm. Data also were collected on subjects' compliance,

as previously defined. The demands included for each subject are listed in Table 4-1.

The frequency of therapist verbal instruction, reinforcer delivery (i.e., escape and edible

item, if applicable), and response blocking onset and offset also was recorded. Additionally,

because escape and blocking periods were not always equal, duration data on these measures

were recorded. As in Study 1, reinforcer consumption time during the escape intervals was

subtracted from session time when calculating response rates, although blocked responses were

included in the corrected response rates.

Interobserver agreement was calculated as previously described. Mean reliability scores

were as follows: Ethan, 96.5% for aggression (range, 85.9% to 100%), 96.8% for compliance

(range, 90% to 100%), 94.5% for therapist instructions (range, 83.3% to 100%), 95.6% for

reinforcer delivery (range, 86.7% to 100%), 99.1% for blocking onset (range, 95.8% to 100%),

and 98.4% for blocking offset (range, 90.8% to 100%); Keith, 97% for property destruction

(range, 82.5% to 100%), 97.9% for compliance (range, 90% to 100%), 96% for therapist

instructions (range, 88.3% to 100%), 96.3% for reinforcer delivery (range, 86.7% to 100%),

97.9% for blocking onset (range, 86.7% to 100%), and 98.8% for blocking offset (range, 95% to

100%); and Kendra, 97.1% for SIB (range, 86.4% to 100%), 95.4% for compliance (range, 71%

to 100%), 95.3% for therapist instructions (range, 80.6% to 100%), 95.0% for reinforcer delivery









(range, 80.4% to 100%), 98.8% for blocking onset (range, 91.7% to 100%), and 99.4% for

blocking offset (range, 93.3% to 100%).

Procedures

A concurrent schedule was used to evaluate the effects of negative reinforcement quality

on compliance and on problem behavior. Across all phases, problem behavior produced escape

from the task demands, whereas compliance did or did not result in escape. As in Study 1,

treatment conditions are labeled with two symbols; the first symbol denotes the consequences for

compliance, and the second symbol denotes the consequence for problem behavior.

Baseline (Praise/ Sr): Procedures were similar to the demand condition of the FA.

Compliance resulted in brief verbal praise followed by another task demand. Problem behavior

produced 30-s escape.

Equal Escape (S'-/ S-): Procedures were similar to those used in baseline, except that

compliance also produced a 30-s break.

Low Quality (LQ) Negative Reinforcement for Problem Behavior (S'/ LQ Sr):

Compliance continued to produce 30-s escape. However, attempts to engage in problem behavior

now were blocked by briefly interrupting the response with the minimum amount of contact

necessary to prevent problem behavior.

Positive Reinforcement for Compliance and LQ Negative Reinforcement for Problem

Behavior (S-/ LQ S'): This condition was similar to the previous Sr-/ LQ Sr- condition, except

that an HP edible item now was delivered contingent on compliance (i.e., no break was

delivered). Problem behavior continued to be blocked for the duration of its occurrence, as in the

previous condition.









Experimental Design

A reversal design was used to establish experimental control. The A condition consisted of

baseline, the B condition consisted of equal Sr/ Sr-, the C condition consisted of Sr/ LQ Sr-, and

the D condition consisted of S+/ LQ Sr. Treatment conditions were implemented sequentially,

such that a given condition was implemented only after the previous condition was shown to be

ineffective.

Results

Table 4-2 summarizes means and ranges for subjects' problem behavior and compliance

across baseline and treatment conditions. Figure 4-1 shows results for Ethan, Keith, and Kendra.

The equal Sr-/ Sr- condition produced no reliable decrease in problem behavior for any subject,

although Kendra's compliance improved somewhat. When problem behavior was blocked (S-/

LQ Sr- condition), Ethan's and Keith's problem behavior (attempts) decreased to near-zero

levels, and both subjects showed large increases in compliance. Following a return to baseline,

these effects were replicated in a subsequent Sr-/ LQ Sr- condition. Kendra showed a different

pattern of results when blocking was implemented. Her rate of hand biting increased markedly

during the S-/ LQ Sr- condition. However, when a preferred edible item was delivered for

compliance in the Sr/ LQ Sr- condition, Kendra's hand biting immediately decreased to zero

rates, and her task completion increased to near 100%. Following a return to baseline, treatment

effects were replicated in the final S+/ LQ Sr- phase, as Kendra did not engage in any hand biting

for several sessions, and she complied with the vast majority of task demands.

In summary, 2 of 3 subjects (Ethan and Keith) showed immediate reductions in problem

behavior when response blocking was implemented, even though it resulted in escape from task

demands following problem behavior. Concomitant improvements in their compliance also were

observed in this Sr-/ LQ S'- condition, even though the contingency for compliance remained









unchanged. By contrast, Kendra only showed sustained improvements in problem behavior and

compliance when compliance produced an apparently more potent positive reinforcer (S+/ LQ

Sr- condition).








Baseline
(BL) Sr-/Sr-


SJ,


Sr- / Sr-





*s. k


BL Sr- / LQSr-


Sr-/ LQ Sr-I
BL Sr+ / LQ Sr-

jjMt^blfLt~


Kendra
***e***********


5 10 15 20 25 30 35 40 45 50 55 60 6


SESSIONS

Figure 4-1. Treatment results for Ethan, Keith, and Kendra in Study 2. (* The asterisk above
Keith's data point for problem behavior in the first Sr/ LQ Sr- session [session #25]
indicates that this session was terminated early [at 5-min].)


000 %


i









CHAPTER 5
DISCUSSION

The present studies examined the influence of quantitative and qualitative parameters of

negative reinforcement on escape-maintained behavior in the absence of EXT. The magnitude of

escape for compliance (Study 1) and quality of escape for problem behavior (Study 2) were

manipulated to determine their relative effects on compliance and problem behavior that

occurred in the context of demands. Taken together, results indicated that very small breaks

following problem behavior may be sufficient to maintain problem behavior that is sensitive to

escape as a reinforcer (Study 1), but that reducing the quality of negative reinforcement for

problem behavior via blocking may be effective even though task demands contingently are

removed for a period of time (Study 2).

Results of Study 1 indicated that enhancing the magnitude (duration) of negative

reinforcement for compliance, beyond that for problem behavior, had little therapeutic effect

when problem behavior continued to produce escape. Although 2 of 7 subjects (Emma and

Braxton) demonstrated reductions in problem behavior when equal escape durations were

available for both response options, the remaining 5 subjects' problem behavior failed to

decrease even when the duration of escape for compliance was increased relative to that for

problem behavior. These data indicate that negative reinforcement for compliance is unlikely to

be effective without EXT, but if it is, relative magnitudes of escape for compliance versus

problem behavior seem unimportant. These findings are consistent with both basic and applied

research, which generally has shown inconsistent or complex relations between reinforcement

magnitude and response rate (Reed, 1991; Reed & Wright, 1988; Trosclair-Lasserre, Lerman,

Call, Addison, & Kodak, 2008), and further suggest that negative reinforcement magnitude may

be a relatively weak parameter of reinforcement (see Lerman et al., 2002, for a discussion).









However, it is possible that additional (uncontrolled) features of the experiment contributed to

the negative results obtained. For example, although we included only one-step tasks that

required minimal response time, it is possible that, if completing a task required more time than

engaging in problem behavior, compliance with demands resulted in an increased delay to

reinforcement. Given that reinforcer immediacy has been found to be a highly potent determinant

of reinforcement effects (e.g., Neef, Mace, & Shade, 1993; Neef et al., 2005; Rachlin, 1974), one

might expects subjects to allocate their responding toward the option that produced more

immediate reinforcement in this case, problem behavior. Although most applied research in

this area has evaluated parameters of positive reinforcement, a notable exception is a study by

Solnick, Kannenberg, Eckerman, and Waller (1980) who, using 90-dB white noise as the

negative reinforcer, found that subjects preferred briefer, more immediate escape (i.e., 90-s

escape delivered immediately) over longer, more delayed escape (i.e., 120-s escape delivered

after 60 s). In short, results of Study 1 extend the literature in suggesting that enhancing the

magnitude of negative reinforcement for an appropriate competing response (compliance) may

not be effective when problem behavior maintained by escape continues to be reinforced. These

results perhaps are not all that surprising. That is, because problem behavior continued to be

negatively reinforced, subjects simply had to engage in more problem behavior in the enhanced

reinforcement magnitude conditions to obtain similar durations of escape (as was provided for

compliance). The clinical implication of these negative findings is important because the

delivery of a longer break following task completion is an obvious treatment strategy that one

might consider when attempting to reduce problem behavior that occurs in the context of

demands. Although this strategy may seem reasonable, our data suggest that care providers









should be cautious not to provide a break following problem behavior no matter how brief-

particularly when compliance is negatively reinforced.

Results of Study 1 also suggested that providing a preferred edible item contingent on

compliance may not be effective in the absence of escape EXT. Four of 5 subjects continued to

show baseline rates of problem behavior and (with the exception of John) compliance during the

Sr/ Sr- condition. These results were unexpected and contradict those of previous research,

which generally has shown positive reinforcement to compete quite well with negative

reinforcement (i.e., Kodak, Lerman, Volkert, & Trosclair, 2007; Lalli et al., 1999). Several

factors may have contributed to the negative results obtained for the majority of our subjects in

the Sr+/ Sr- condition. First, as previously noted, it is possible that compliance was associated

with a relative delay to reinforcement. For those subjects for whom immediacy was a more

potent parameter of reinforcement (i.e., than quality), it would be expected that they would

allocate their responding toward problem behavior. Similarly, if compliance was the more

effortful response, one might expect the subjects to allocate their responding toward problem

behavior (cf Horner & Day, 1991). Third, it is possible that positive reinforcement for

compliance was ineffective because it was not a functional reinforcer for problem behavior.

Some studies that have shown beneficial effects under the Sr+/ Sr- contingency included subjects

whose problem behaviors were maintained by both negative and positive reinforcement (i.e.,

DeLeon et al., 2001; Piazza et al., 1997); thus, perhaps it is not surprising that positive

reinforcement for compliance was the superior treatment in these studies. However, because we

did not include a tangible condition in the FAs of most of our subjects, we cannot conclude that

their problem behaviors were not also sensitive to tangible reinforcement. Furthermore, because

research has shown that positive reinforcement for compliance can compete with problem









behavior that is maintained solely by escape (i.e., Lalli et al.), this interpretation seems unlikely.

Fourth, the contingencies for compliance were not described to any of our subjects, which is a

procedural difference from studies showing that S+/ Sr- decreased problem behavior maintained

by escape only (i.e., Hoch et al., 2002; Lalli et al.). Additionally, it is remotely possible that the

subjects' lengthy history of escape for problem behavior biased their responding toward this

alternative and contributed to the negative effects obtained in the Sr+/ Sr- condition, as well as in

the previous conditions wherein problem behavior continued to be negatively reinforced.

Finally, escape EXT was necessary to decrease the remaining 4 subjects' problem

behavior in Study 1. Given the rapid reductions in problem behavior that were achieved when

EXT was implemented, results of Study 1 indicated that (when possible) EXT should be used as

the preferred method of treatment. These findings are supported by numerous studies that have

shown that EXT may be a critical component of treatment (i.e., Mazaleski et al., 1993; Zarcone

et al., 1993; 1994a; 1994b).

Results of Study 2 suggested the possibility of altering a different dimension of negative

reinforcement quality when EXT for problem behavior is not feasible. Two subjects (Ethan

and Keith) exhibited reductions in problem behavior when response blocking was implemented

during the escape interval even though problem behavior also resulted in the cessation of task

demands for a period of time. These subjects also showed improvements in compliance when

problem behavior was blocked during escape, despite the fact that the contingency for

compliance remained unchanged. These results coincide with previous research, which generally

has shown that compliance improves without additional contingencies when problem behavior

maintained by escape is decreased (Iwata et al., 1990). These findings perhaps raise the question

as to what mechanism was responsible for the reduced rates of problem behavior obtained for









both Ethan and Keith. Previous research on the effects of response blocking on behavior

maintained by automatic reinforcement suggests that blocking may function as either punishment

(Lerman & Iwata, 1996a) or EXT (Smith, Russo, & Le, 1999). It is possible that similar

behavioral processes were responsible for the decreased rates of problem behavior observed for

these subjects in the Sr-/ LQ Sr- condition, particularly considering that the quality manipulation

involved a deterioration of conditions for problem behavior. Regardless, results for Ethan and

Keith extend previous research (e.g., Peck et al., 1996) in demonstrating that blocking (alone)

may be an effective treatment for problem behavior maintained by negative reinforcement.

Furthermore, these results perhaps suggest that negative reinforcement quality also may be an

influential parameter.

By contrast, Kendra exhibited a significant increase in problem behavior in the Sr-/ LQ Sr-

condition. Thus, blocking was not only ineffective for Kendra but in the absence of additional

contingencies for compliance resulted in a worsening of problem behavior. Two factors may

have contributed this. First, it is remotely possible that blocking somehow enhanced (rather than

reduced) the quality of reinforcement that her hand biting produced in the Sr-/ LQ Sr- condition.

For example, anecdotal reports indicated that Kendra often laughed, smiled, and swayed her head

back and forth (which she typically would do when playing) when blocking was implemented.

Although the results of Kendra's FA did not suggest an attention function, she did not contact the

contingency for problem behavior in any of the attention sessions (see Figure 2-1). Thus,

although unlikely, perhaps her hand biting also was maintained by attention, but that her FA (as

configured) was not sensitive enough to capture this function. A more probable explanation is

that blocking, because of its aversive properties, elicited higher rates of problem behavior in the

Sr-/ LQ Sr- condition. Previous research has shown that aversive stimuli, when used as negative









reinforcers, can acquire eliciting properties (Powell & Peck, 1969; Sidman, Hermstein, &

Conrad, 1957). Given the nature of Kendra's problem behavior, however, it was not feasible to

remove the blocking component because of the risk of self-harm that her hand biting posed.

Therefore, positive reinforcement in the form of preferred edible items was delivered for

compliance while problem behavior continued to be blocked. An immediate and sustained

decrease in Kendra's rate of hand biting was observed when the contingency for compliance was

changed from negative to positive reinforcement. A marked increase in her level of compliance

also was observed in this S+/ LQ Sr- condition. Thus, contrary to the results of Study 1, Kendra's

results coincide with previous research, which largely has shown that problem behavior

maintained (at least in part) by escape may be treated without EXT by delivering high quality

positive reinforcers contingent on compliance (e.g., DeLeon et al., 2001; Lalli et al., 1999).

Collectively, these results point to some directions for future research on competing

contingencies of negative reinforcement for behavior that occurs in the context of demands.

First, it is remotely possible that the subjects' lengthy history of escape for problem behavior

rendered the enhanced reinforcement magnitude manipulation a very slow acting treatment, but

one that might have been effective if given enough time. Future research could examine this

possibility by exposing the subjects to the enhanced reinforcement magnitude condition for

longer periods of time than they were in this study. Because treatment efficiency is an important

consideration, however, the utility of this approach may be questionable. Second, perhaps the

magnitudes we used in this study were not sufficiently different to shift the subjects' response

allocation from problem behavior to compliance. Additional research therefore could examine

the effects of negative reinforcement magnitude by providing considerably longer breaks

contingent on compliance from the outset, relative to that for problem behavior. For example,









sessions initially could be terminated following the first compliant response (e.g., resulting in a 9

min break or more if the subject complied immediately). As sustained improvements in the

subjects' behavior are demonstrated, the rate of task demands could be increased while relatively

larger magnitude of negative reinforcement continue to be available for compliance. Such an

approach would combine both antecedent (demand fading) and consequent (DRA) interventions.

Although demand fading has been shown to be ineffective in the absence of EXT (Zarcone et al.,

1994b), it is possible that treatment effects could be achieved by combining the two procedures.

Similarly, perhaps delivering larger magnitudes of negative reinforcement for compliance would

prove effective if used in conjunction with an errorless learning or instructional fading procedure

(Weeks & Gaylord-Ross, 1981). For example, difficult features of the task first could be

removed by providing escape contingent on an appropriate break request. This might reduce any

delay to reinforcement that could be associated with compliance; if so, the subjects might be

more likely to allocate their responding toward the appropriate response. If problem behavior

decreases to low rates, difficult features of the task could be reintroduced while the magnitude of

escape for compliance is increased (as the contingency is changed from DRA [mand] to DRA

[compliance]). Alternatively, future research could examine the relative effects of negative

reinforcement magnitude on compliance and on problem behavior following an EXT baseline.

Previous research has shown that problem behavior might be treated without EXT by

capitalizing on such sequence effects (e.g., Vollmer, Roane, Ringdahl, & Marcus, 1999). The

clinical implications of this approach, if effective, would be that sustained reductions in escape-

maintained behavior might be achieved in the relevant environment ii iil,,,t EXT by first treating

problem behavior in ith EXT in a clinic setting (i.e., with skilled therapists).









Future research also could examine the conditions under which positive reinforcement for

compliance will and will not compete with problem behavior maintained by escape. Previous

research has shown that the success of positive reinforcement is dependent on factors such as the

subject's preference for the item that is delivered contingent on compliance (i.e., high- versus

low-preferred items; Kodak et al., 2007) and the response requirements of the task itself (DeLeon

et al., 2001). Results of Studies 1 and 2 extend these findings in suggesting that the quality of

negative reinforcement that problem behavior produces also might influence the effectiveness of

the Sr/ Sr- procedure. That is, when problem behavior produces escape in the absence of

additional consequences (i.e., no blocking), Sr+ for compliance might be largely ineffective

(Study 1); however, when the quality of escape for problem behavior is reduced via blocking, Sr+

for compliance may be rendered more effective (Study 2). Additional studies could evaluate the

conditions under which Sr+/ Sr- is and is not an effective treatment for escape maintained

behavior by examining the extent to which low rates of problem behavior are maintained under

increasing schedule requirements for compliance (e.g., Lalli et al., 1999) or when Sr+/ S- is

implemented for longer periods of time (e.g., across the school day). Also, future research

perhaps could compare the utility of the Sr+/ S- procedure at decreasing problem behavior that is

maintained solely by escape versus problem behavior that is maintained by both negative and

positive reinforcement.

Additionally, it may be worth noting that our subjects differed on several demographic

characteristics such as age, diagnosis and functioning level, history of reinforcement for problem

behavior, and so forth. Therefore, it is somewhat possible that these characteristics contributed

(at least in part) to the idiosyncratic results that were obtained in both Study 1 and Study 2.

Future research may examine this possibility by evaluating the effects of negative reinforcement









magnitude and quality on the escape-maintained behavior of individuals whose characteristics

are more similar.

Finally, our reason for examining the effects of competing contingencies for problem

behavior maintained by escape is that caregivers often do not implement EXT which leads to

questions about why not, and whether there are ways to improve caregivers' correct use of this

procedure. Additional research in this area therefore is needed. One approach would be to

conduct descriptive analyses (Bijou, Peterson, & Ault, 1968) of caregivers' use of escape EXT

during naturally occurring demand situations, which would provide information regarding what

actually happens when tasks are presented. For example, is it simply a matter of inconsistent

(intermittent) application? Or do suspected problems (i.e., physical resistance on the part of the

client) actually occur? This information might prove useful in designing strategies that may

improve the consistency with which escape EXT is implemented by caregivers across relevant

environments.

In summary, these studies extend previous research on treatments without EXT by

evaluating the effects of quantitative and qualitative parameters of negative reinforcement on

compliance and on problem behavior that occurs in the context of demands. Although positive

reinforcement long has been recognized as a potent source of reinforcement for problem

behavior, and treatment for this function generally is well understood, the role that negative

reinforcement plays in the maintenance of both appropriate and problem behavior shown by

individuals with developmental disabilities is less well developed (cf. Iwata, 1987). The utility of

negative reinforcement for an appropriate competing response (compliance) in the absence of

EXT is not evident, and the use of positive reinforcement for appropriate behavior is not simply

a matter of competition between different reinforcers, but competition between different









contingencies. Therefore, a number of parameters and contingency relations have yet to be

explored in the treatment of problem behavior maintained by escape, and the hope is that this

study will assist in guiding that line of research.









Table 2-1. Subiect characteristics


Name


Age


Classification


Emma 11 Down syndrome, MR



Braxton 19 Cerebral palsy, seizure disorder,
MR


Tim



Gary


21 Angelman syndrome, seizure
disorder, MR


12 Autism


John 6 Autism



Rita 17 Angelman syndrome, MR




Keith 43 Seizure disorder, MR





Ethan 4 PDD-NOS


Kendra 10


Seizure disorder, retinopathy of
the eye


Definition of Target Problem Behaviors
Property destruction (throwing items a
distance of 6" or more, tipping over
furniture)

SIB (hand biting: inserting palm past plane
of the lips while forcefully biting down)

Property destruction (tearing paper or
clothing by at least 1" or audibly, throwing
or swiping items a distance of 6" or more)

Aggression (hitting or kicking from a
distance of at least 6" or audibly, head
butting)

Property destruction (throwing or swiping
objects a distance of 6" or more, knocking
over furniture)

Aggression (hair pulling, hitting from a
distance of at least 6" or audibly, pushing
such that the therapist or wheelchair
moves)

Property destruction (throwing items a
distance of 6" or more, ripping paper,
hitting walls or furniture from a distance of
at least 6" or audibly, tearing paper off of
walls, knocking over furniture)

Aggression (hitting or kicking from a
distance of at least 6", biting or attempts to
bite by placing mouth within 1" of
therapists body part, scratching by moving
fingers at least 1" along therapist's skin,
pushing therapist with his body)

SIB (hand biting: inserting palm past plane
of the lips and biting down with teeth-to-
skin contact)









Table 3-1. Task demands included for each subject in Study 1
Name Definition of Task Demands
Emma Sit at desk or table, place objects in a bin, touch body part (e.g., hair, belly, nose)

Braxton Touch card, hand therapist card, touch body part (e.g., ear, head, belly, elbow)

Tim Sit in chair, fold paper or clothing, stack paper, hand therapist paper, pick up trash, put
items in trash bag

Gary Object identification (i.e., "point to [x]"), write letter "G"

John Sit in chair, establish eye contact with the therapist (i.e., "look at me"), object
identification (i.e., "touch [x]"), hand therapist object, place objects in bin

Rita Touch card, hand therapist card, touch body part (e.g., head, nose, belly)

Keith Sit in chair, draw a line, wipe surface, hand experimenter object, put on shoe









Table 3-2. Means and ranges of dependent measures for each


Name
Emma


Condition
BL
30/30


Braxton BL
30/30
120/30


Tim


Gary






John


Rita






Keith


BL
30/30
120/30
120/5
r+/ Sr-

BL
30/30
120/30
120/5
r+/ Sr-
Sr+/ EXT

BL
30/30
120/30
120/5
r+/ Sr-
Sr+/ EXT

BL
30/30
120/30
120/5
r+/ Sr-
Sr+/ EXT

BL
30/30
120/30
120/5
r+/ Sr-
Sr+/ EXT


Problem behavior


4.4 rpm (range, 0.36 to 9.87 rpm)
0.98 rpm (range, 0 to 2.86 rpm)

1.0 rpm (range, 0.24 to 1.68 rpm)
0.02 rpm (range, 0 to 0.23 rpm)
0.05 rpm (range, 0 to 0.53 rpm)

6.86 rpm (range, 1.53 to 12.3 rpm)
2.87 rpm (range, 0 to 8.46 rpm)
3.03 rpm (range, 1.08 to 7.14 rpm)
2.57 rpm (range, 0.65 to 5.52 rpm)
0.16 rpm (range, 0 to 0.69 rpm)

17.8 rpm (range, 3.14 to 28.4 rpm)
17.7 rpm (range, 13 to 25.4 rpm)
27.1 rpm (range, 20 to 31.1 rpm)
32.4 rpm (range, 30.3 to 33.4 rpm)
25.2 rpm (range, 18 to 37.5 rpm)
0.08 rpm (range, 0 to 0.1 rpm)

2.22 rpm (range, 1.66 to 3.27 rpm)
1.77 rpm (range, 0.9 to 2.39 rpm)
1.82 rpm (range, 1.54 to 2.23 rpm)
3.4 rpm (range, 2.54 to 3.92 rpm)
2.49 rpm (range, 1.08 to 4.2 rpm)
0.37 rpm (range, 0 to 1.2 rpm)

7.18 rpm (range, 1.85 to 12.3 rpm)
7.86 rpm (range, 2.56 to 11.1 rpm)
6.96 rpm (range, 1.71 to 19.1 rpm)
3.29 rpm (range, 0.86 to 8.37 rpm)
3.51 rpm (range, 0.51 to 4.96 rpm)
0.56 rpm (range, 0 to 1.3 rpm)

9.79 rpm (range, 5.35 to 14.1 rpm)
12.6 rpm (range, 8.29 to 15.7 rpm)
14.5 rpm (range, 8.3 to 20.5 rpm)
9.75 rpm (range, 3.14 to 25.5 rpm)
7.0 rpm (range, 5.7 to 8.6 rpm)
0.87 rpm (range, 0 to 2.8 rpm)


subject Study 1
Compliance


14.5% (range,
40.4% (range,

4.16% (range,
17.6% (range,
20.1% (range,

15.0% (range,
56.8% (range,
59.4% (range,
57.2% (range,
89.4% (range,


0 to 27.8%)
9.5 to 64.7%)

Oto 13%)
10.7 to 21.9%)
14.8 to 28.6%)

0 to 45.8%)
25.0 to 92.3%)
33.3 to 83.3%)
33.3 to 83.3%)
78.3 to 98.1%)


5.17% (range,
11.4% (range,
7.03% (range,
20.7% (range,
16.6% (range,
13.3% (range,

8.73% (range,
12.0% (range,
26.3% (range,
29.7% (range,
32.3% (range,
56.2% (range,


Oto 16.7%)
0 to 31.3%)
Oto 18.2%)
2.44 to 50.0%)
7.4 to 30.0%)
10.6 to 14.9%)

0 to 14.3%)
0 to 27.8%)
15.4 to 44.4%)
15.8 to 45.5%)
27.0 to 42.0%)
37.1 to 76.7%)


Summary data for the first BL phase and last effective treatment phase are reported.


14.4% (range, 5.26 to 36%)
6.93% (range, 5.55 to 11.8%)
6.27 % (range, 5.88 to 6.67%)
1.95% (range, 1.79 to 2.22%)
5.26% (range, 5.26 to 5.26%)
98.9% (range, 96.3 to 100%)

5.01% (range, O to 9.52%)
16.4% (range, O to 62.5%)
8.51% (range, 5.56 to 13.3%)
8.91 (range, 6.9 to 11.5%)
37.2% (range, 17.7 to 52.2%)
34.5% (range, 15.0 to 58.3%)









Table 4-1. Task demands included for each subject in Study 2
Name Definition of Task Demands
Ethan Sit down, stand up, touch body part (e.g., head, nose, ear), "count to (x)", object
identification (e.g., "show me [x]," "point to the [x] on the left/right," etc.)

Keith Stack chairs, string bead, put puzzle piece in puzzle, zip bag, put on jacket, put on
shoe

Kendra Sit down, stand up, clap hands, put on shirt, put on shoe



Table 4-2. Means and ranges of dependent measures for each subject Study 2
Name Condition Problem behavior Compliance
Ethan BL 15.2 rpm (range, 11.7 to 20.7 rpm) 12.8% (range, 0 to 34.7%)
30/30 12.6 rpm (range, (9.15 to 16.5 rpm) 16.2% (range, 5.5 to 29.4%)
Sr-/ LQ Sr- 0.15 rpm (range, 0 to 1.65 rpm) 90.7% (range, 62.5 to 100%)

Keith BL 10.6 rpm (range, 3.0 to 18.5 rpm) 14.6% (range, 0 to 38.9%)
30/30 9.97 rpm (range, 2.11 to 19.3 rpm) 23.6% (range, 0 to 60.0%)
Sr-/ LQ Sr- 0.93 rpm (range, 0 to 18.1 rpm) 67.7% (range, 4.3 to 80.0%)

Kendra BL 1.94 rpm (range, 0.5 to 4.62 rpm) 1.92% (range, 0 to 11.0%)
30/30 1.58 rpm (range, 0.38 to 4.0 rpm) 11.4% (range, O to 40.0%)
Sr-/ LQ Sr- 5.69 rpm (range, 3.11 to 7.55 rpm) 11.8% (range, 10.3 to 12.5%)
Sr+/ LQ Sr- 0.01 rpm (range, 0 to 0.1 rpm) 97.8% (range, 93.9 to 100%)
Summary data for the first BL phase and last effective treatment phase are reported.









LIST OF REFERENCES


Bijou, S. W., Peterson, R. F., & Ault, M. H. (1968). A method to integrate descriptive and
experimental field studies at the level of data and empirical concepts. Journal ofApplied
Behavior Analysis, 1, 175-191.

Carr, E. G. (1977). The motivation of self-injurious behavior: A review of some hypotheses.
Psychological Bulletin, 84, 800-816.

Carr, E. G., & Durand, M. V. (1985). Reducing behavior problems through functional
communication training. Journal ofApplied Behavior Analysis, 18, 111-126.

Carr, J. E., Bailey, J. S., Ecott, C. L., Lucker, K. D., & Weil, T. M. (1998). On the effects of
noncontingent delivery of differing magnitudes of reinforcement. Journal of Applied
Behavior Analysis, 31, 313-321.

Carr, J. E., Coriaty, S., Wilder, D. A., Gaunt, B. T., Dozier, C. L., Britton, L. N., Avina, C., &
Reed, C. L. (2000). A review of noncontingentt" reinforcement as treatment for the
aberrant behavior of individuals with developmental disabilities. Research in
Developmental Disabilities, 21, 377-391.

Cataldo, M. F. (1991). The effects of punishment and other behavior reducing procedures on the
destructive behavior of persons with developmental disabilities. In U.S. Department of
Health and Human Services, Treatment of destructive behaviors in persons n ilh
developmental disabilities (pp. 231-341) (NIH Publication No. 91-2410). Bethesda, MD:
National Institutes of Health.

Catania, A. C. (1963). Concurrent performances: A baseline for the study of reinforcement
magnitude. Journal of the Experimental Analysis ofBehavior, 6, 299-300.

Cipani, E., & Spooner, F. (1997). Treating problem behaviors maintained by negative
reinforcement. Research in Developmental Disabilities, 18, 329-342.

Conners, J., Iwata, B. A., Kahng, S. W., Hanley, G. P., Worsdell, A. S., & Thompson, R. H.
(2000). Differential responding in the presence and absence of discriminative stimuli
during multielement functional analyses. Journal ofApplied Behavior Analysis, 33, 299-
308.

DeLeon, I. G. & Iwata, B. A. (1996). Evaluation of a multiple-stimulus presentation format for
assessing reinforcer preferences. Journal ofApplied Behavior Analysis, 29, 519-533.

DeLeon, I. G., Neidert, P. L., Anders, B. M., & Rodriguez-Catter, V. (2001). Choices between
positive and negative reinforcement during treatment for escape-maintained behavior.
Journal ofApplied Behavior Analysis, 34, 521-525.









Derby, K. M., Wacker, D. P., Sasso, G., Steege, M., Northup, J., Cigrand, K., & Asmus, J.
(1992). Brief functional assessment techniques to evaluate aberrant behavior in an
outpatient setting: A summary of 79 cases. Journal ofApplied Behavior Analysis, 25,
713-721.

Egel, A. L. (1981). Reinforcer variation: Implications for motivating developmentally disabled
children. Journal ofApplied Behavior Analysis, 14, 345-350.

Ferster, C. B., & Skinner, B. F. (1957). Schedules of reinforcement. New York: Appleton-
Century-Crofts.

Fisher, W. W., & Mazur, J. E. (1997). Basic and applied research on choice responding. Journal
ofApplied Behavior Analysis, 30, 387-410.

Fisher, W., Piazza, C. C., Bowman, L. G., Hagopian, L. P., Owens, J. C., & Slevin, I. (1992). A
comparison of two approaches for identifying reinforcers for persons with severe and
profound disabilities. Journal ofApplied Behavior Analysis, 25, 491-498.

Goh, H., & Iwata, B. A. (1994). Behavioral persistence and variability during extinction of self-
injury maintained by escape. Journal ofApplied Behavior Analysis, 27, 173-174.


Golonka, Z., Wacker, D., Berg, W., Derby, K. M., Harding, J., & Peck, S. (2000). Effects of
escape to alone versus escape to enriched environments on adaptive and aberrant
behavior. Journal ofApplied Behavior Analysis, 33, 243-246.

Hanley, G. P., Iwata, B. A., & McCord, B. E. (2003). Functional analysis of problem behavior: A
review. Journal ofApplied Behavior Analysis, 36, 147-185.

Hoch, H., McComas, J. J., Thompson, A. L., & Paone, D. (2002). Concurrent reinforcement
schedules: Behavior change and maintenance without extinction. Journal of Applied
Behavior Analysis, 35, 155-169.

Horner, R. H. & Day, H. M. (1991). The effects of response efficiency on functionally equivalent
competing behaviors. Journal ofApplied Behavior Analysis, 24, 719-732.

Individuals with Disabilities Education Act Amendments of 1997, 20 U.S.C. 1414(d) (Supp. III
1997).

Iwata, B. A. (1987). Negative reinforcement in applied behavior analysis: An emerging
technology. Journal ofApplied Behavior Analysis, 20, 361-378.

Iwata, B. A., Dorsey, M. F., Slifer, K. J., Bauman, K. E., & Richman, G. S. (1994). Toward a
functional analysis of self-injury. Journal ofApplied Behavior Analysis, 27, 197-209.
Reprinted from Analysis and Intervention in Developmental Disabilities, 2, 3-20, 1982.









Iwata, B. A., Kahng, S., Wallace, M. D., & Lindberg, J. L. (2000). The functional analysis model
of behavioral assessment. In J. Austin & J. E. Carr (Eds.), Handbook of applied behavior
analysis (pp. 61-89). Reno, NV: Context Press.

Iwata, B. A., Pace, G. M., Cowdery, G. E., & Miltenberger, R. G. (1994). What makes extinction
work: An analysis of procedural form and function. Journal ofApplied Behavior
Analysis, 27, 131-144.

Iwata, B. A., Pace, G. M., Dorsey, M. F., Zarcone, J. R., Vollmer, T. R., Smith, R. G., Rodgers,
T. A., Lerman, D. C., Shore, B. A., Mazaleski, J. L., Goh, H., Cowdery, G. E., Kalsher,
M. J., McCosh, K. C., & Willis, K. D. (1994). The functions of self-injurious behavior:
An experimental-epidemiological analysis. Journal ofApplied Behavior Analysis, 27,
215-240.

Iwata, B. A., Pace, G. M., Kalsher, M. J., Cowdery, G. E., & Cataldo, M. F. (1990).
Experimental analysis and extinction of self-injurious escape behavior. Journal of
Applied Behavior Analysis, 23, 11-27.

Iwata, B. A., Vollmer, T. R., Zarcone, J. R., & Rodgers, T. A. (1993). Treatment classification
and selection based on behavioral function. In R. Van Houten & S. Axelrod (Eds.),
Behavior analysis and treatment (pp. 102-125). New York: Plenum.

Kodak, T., Lerman, D. C., Volkert, V. M., & Trosclair, N. (2007). Further examination of factors
that influence preference for positive versus negative reinforcement. Journal ofApplied
Behavior Analysis, 40, 25-44.

Kodak, T., Miltenberger, R. G., & Romaniuk, C. (2003). The effects of differential negative
reinforcement of other behavior and noncontingent escape on compliance. Journal of
Applied Behavior Analysis, 36, 379-382.

Lalli, J. S., & Casey, S. D. (1996). Treatment of multiply controlled problem behavior. Journal
ofApplied Behavior Analysis, 29, 391-395.

Lalli, J. S., Vollmer, T. R., Progar, P. R., Wright, C., Borrero, J., Daniel, D., Hoffner Barthold,
C., Tocco, K., & May, W. (1999). Competition between positive and negative
reinforcement in the treatment of escape behavior. Journal ofApplied Behavior Analysis,
32, 285-296.

Lerman, D. C., & Iwata, B. A. (1996). A methodology for distinguishing between extinction and
punishment effects associated with response blocking. Journal ofApplied Behavior
Analysis, 29, 231-233.

Lerman, D. C., & Iwata, B. A. (1996). Developing a technology for the use of operant extinction
in clinical settings: An examination of basic and applied research. Journal of Applied
Behavior Analysis, 29, 345-382.









Lerman, D. C., Iwata, B. A., & Wallace, M. D. (1999). Side effects of extinction: Prevalence of
bursting and aggression during treatment of self-injurious behavior. Journal ofApplied
Behavior Analysis, 32, 1-8.

Lerman, D. C., Kelley, M. E., Van Camp, C. M., & Roane, H. S. (1999). Effects of
reinforcement magnitude on spontaneous recovery. Journal ofApplied Behavior
Analysis, 32, 197-200.

Lerman, D. C., Kelley, M. E., Vorndran, C. M., Kuhn, S. A. C., & LaRue, R. H. Jr. (2002).
Reinforcement magnitude and responding during treatment with differential
reinforcement. Journal ofApplied Behavior Analysis, 35, 29-48.

Mace, F. C., & Belfiore, P. (1990). Behavioral momentum in the treatment of escape-motivated
stereotypy. Journal of Applied Behavior Analysis, 23, 507-514.

Mace, F. C., Neef, N. A., Shade, D., & Mauro, B. C. (1996). Effects of problem difficulty and
reinforcer quality on time allocated to concurrent arithmetic problems. Journal ofApplied
Behavior Analysis, 29, 11-24.

Marcus, B. A., & Vollmer, T. R. (1995). Effects of differential negative reinforcement on
disruption and compliance. Journal ofApplied Behavior Analysis, 28, 229-230.

Mazaleski, J. L., Iwata, B. A., Vollmer, T. R., Zarcone, J. R., & Smith, R. G. (1993). Analysis of
the reinforcement and extinction components in DRO contingencies with self-injury.
Journal ofApplied Behavior Analysis, 26, 143-156.

McComas, J. J., Goddard, C., & Hoch, H. (2002). The effects of preferred activities during
academic work breaks on task engagement and negatively reinforced destructive
behavior. Education and Treatment of Children, 25, 103-112.

Neef, N. A., Mace, F. C., & Shade, D. (1993). Impulsivity in students with serious emotional
disturbance: The interactive effects of reinforcer rate, delay, and quality. Journal of
Applied Behavior Analysis, 26, 37-52.

Neef, N. A., Mace, F. C., Shea, M. C., & Shade, D. (1992). Effects of reinforcer rate and
reinforcer quality on time allocation: Extensions of matching theory to educational
settings. Journal ofApplied Behavior Analysis, 25, 691-699).

Neef, N. A., Marckel, J., Ferreri, S. J., Bicard, D. F., Endo, S., Aman, M. G., Miller, K. m., Jung,
S., Nist, L., & Armstrong, N. (2005). Behavioral assessment of impulsivity: A
comparison of children with and without attention deficit hyperactivity disorder. Journal
ofApplied Behavior Analysis, 38, 23-37.

Neef, N. A., Shade, D., & Miller, M. S. 91994). Assessing influential dimensions of reinforcers
on choice in students with serious emotional disturbance. Journal ofAppliedBehavior
Analysis, 27, 575-583.









Pace, G. M., Ivancic, M. T., & Jefferson, G. (1994). Stimulus fading as treatment of obscenity in
a brain-injured adult. Journal ofApplied Behavior Analysis, 27, 301-305.

Pace, G. M., Iwata, B. A., Cowdery, G. E., Andree, P. J., & McIntyre, T. (1993). Stimulus
(instructional) fading during extinction of self-injurious escape behavior. Journal of
Applied Behavior Analysis, 26, 205-212.

Peck, S. M., Wacker, D. P., Berg, W. K., Cooper, L. J., Brown, K. A., Richman, D., McComas,
J. J., Frischmeyer, P., & Millard, T. (1996). Choice-making treatment of young children's
severe behavior problems. Journal ofApplied Behavior Analysis, 29, 263-290.

Pelios, L., Morren, J., Tesch, D., & Axelrod, S. (1999). The impact of functional analysis
methodology on treatment choice for self-injurious and aggressive behavior. Journal of
Applied Behavior Analysis, 32, 185-195.

Piazza, C. C., Fisher, W. W., Hanley, G. P., Remick, M. L., Contrucci, S. A., & Aitken, T. L.
(1997). The use of positive and negative reinforcement in the treatment of escape-
maintained destructive behavior. Journal ofApplied Behavior Analysis, 30, 279-298.

Powell, R. W., & Peck, S. (1969). Persistent shock-elicited responding engendered by a negative
reinforcement procedure. Journal of the Experimental Analysis ofBehavior, 12, 1049-
1062.

Rachlin, H. (1974). Self-control. Behaviorism, 2, 94-107.

Reed, P. (1991). Multiple determinants of the effects of reinforcement magnitude on free-operant
response rates. Journal of the Experimental Analysis ofBehavior, 55, 109-123.

Reed, P., & Wright, J. E. (1988). Effects of magnitude of food reinforcement on free-operant
response rates. Journal of the Experimental Analysis ofBehavior, 49, 75-85.

Romaniuk, C., Miltenberger, R., Conyers, C., Jenner, N., Jurgens, M., & Ringenberg, C. (2002).
The influence of activity choice on problem behaviors maintained by escape versus
attention. Journal ofApplied Behavior Analysis, 35, 349-362.

Roscoe, E. M., Iwata, B. A., & Rand, M. S. (2003). Effects of reinforcer consumption and
magnitude on response rates during noncontingent reinforcement. Journal ofApplied
Behavior Analysis, 36, 525-539.

Sidman, M., Herrnstein, R. J., & Conrad, D. G. (1957). Maintenance of avoidance behavior by
unavoidable shocks. Journal of Comparative and Physiological Psychology, 50, 553-557.

Smith, R. G., Russo, L., & Le, D. D. (1999). Distinguishing between extinction and punishment
effects of response blocking: A replication. Journal of Applied Behavior Analysis, 32,
367-370.









Smolev, S. R. (1971). Use of operant techniques for the modification of self-injurious behavior.
American Journal of Mental Deficiency, 76, 295-305.

Solnick, J. V., Kannenberg, C. H., Eckerman, D. A., & Waller, M. B. (1980). An experimental
analysis of impulsivity and impulse control in humans. Learning and Motivation, 11, 61-
77.

Trosclair-Lasserre, N. M., Lerman, D. C., Call, N. A., Addison, L. R., & Kodak, T. (2008).
Reinforcement magnitude: An evaluation of preference and reinforcer efficacy. Journal
ofApplied Behavior Analysis, 41, 203-220.

Vollmer, T. R. (1999). Noncontingent reinforcement: Some additional comments. Journal of
Applied Behavior Analysis, 32, 239-240.

Vollmer, T. R., & Iwata, B. A. (1992). Differential reinforcement as treatment for behavior
disorders: Procedural and functional variations. Research in Developmental Disabilities,
13, 393-417.

Vollmer, T. R., Marcus, B. A., & Ringdahl, J. E. (1995). Noncontingent escape as treatment for
self-injurious behavior maintained by negative reinforcement. Journal of Applied
Behavior Analysis, 28, 15-26.

Vollmer, T. R., Roane, H. S., Ringdahl, J. E., & Marcus, B. A. (1999). Evaluating treatment
challenges with differential reinforcement of alternative behavior. Journal of Applied
Behavior Analysis, 32, 9-23.

Weeks, M., & Gaylord-Ross, R. (1981). Task difficulty and aberrant behavior in severely
handicapped students. Journal ofApplied Behavior Analysis, 14, 449-463.

Wilder, D. A., Normand, M., & Atwell, J. (2005). Noncontingent reinforcement as treatment for
food refusal and associated self-injury. Journal ofAppliedBehavior Analysis, 38, 549-
553.

Zarcone, J. R., Iwata, B. A., Hughes, C. E., & Vollmer, T. R. (1993). Momentum versus
extinction effects in the treatment of self-injurious escape behavior. Journal of Applied
Behavior Analysis, 26, 135-136.

Zarcone, J. R., Iwata, B. A., Mazaleski, J. L., & Smith, R. G. (1994). Momentum and extinction
effects on self-injurious behavior and noncompliance. Journal ofAppliedBehavior
Analysis, 27, 649-658.

Zarcone, J. R., Iwata, B. A., Smith, R. G., Mazaleski, J. L., & Lerman, D. C. (1994).
Reemergence and extinction of self-injurious escape behavior during stimulus
(instructional) fading. Journal ofApplied Behavior Analysis, 27, 302-316.









BIOGRAPHICAL SKETCH

Jennifer Hammond completed her bachelor's degree in psychology at the University of

California, Santa Cruz in 1999 while gaining clinical experience with individuals with

developmental disabilities. She subsequently obtained her master's degree in psychology at

California State University, Stanislaus in 2001, where she continued to work and conduct

research with children and adolescents diagnosed with a range of disabilities, including autism.

Jennifer enrolled in the Ph.D. program in behavior analysis at the University of Florida in 2004,

where she focused her studies on disorders of learning and behavior in developmental

disabilities. She conducted clinical research in outpatient clinics, schools, and residential

settings, and served as Clinical Director of a program for individuals with Prader-Willi

Syndrome, while teaching courses in applied behavior analysis. Following graduation, Jennifer

will begin a post-doctoral fellowship in psychiatry at Stanford University School of Medicine,

where she will conduct interdisciplinary research on the neurological and environmental

contributions to various genetic disorders and behavioral phenotypes.





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1 COMPETING CONTINGENCIES FOR ESCAPE BEHAVIOR: EFFECTS OF NEGATIVE REINFORCEMENT MAGNITUDE AND QUALITY By JENNIFER L. HAMMOND A DISSERTATION PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLOR IDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY UNIVERSITY OF FLORIDA 2009

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2 2009 Jennifer L. Hammond

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3 To my family Mom, Dad, and Stephanie

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4 ACKNOWLEDGMENTS I thank Sarah Bloom Carrie Dempsey, and Jenn Fritz for their thoughtful comments and suggestions throughout the course of the study, as well as Tara Fahmie, Jill Harper, Natalie Rolider, and Anne Shroyer for their assistance with overseeing subjects. I also extend my sincere appreciation to Stephen Smith, Donald Stehouw er, and Timothy Vollmer for their guidance and helpful suggestions on this project Most of all, I offer my utmo st gratitude and admiration to Brian Iwata for all of the time, commitment, and e ndless support he provided to this project and to me throughout my career. I consider myself extremely fortunate to have had such a fine model and mentor; I am forever grateful.

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5 TABLE OF CONTENTS page ACKNOWLEDGMENTS ............................................................................................................... 4LIST OF TABLES ...........................................................................................................................7LIST OF FIGURES .........................................................................................................................8LIST OF ABBREVIATIONS ......................................................................................................... .9ABSTRACT ...................................................................................................................... .............10 CHAP TER 1 INTRODUCTION .................................................................................................................. 12Functional Analysis of Problem Behavior .............................................................................. 12Function-Based Treatment Selection ......................................................................................13Treatment of Problem Behavi or Maintained by Escape .........................................................14Noncontingent Reinforcement .........................................................................................14Extinction .................................................................................................................... ....15Differential Reinforcement .............................................................................................. 16Treatment With Escape Extinction ..................................................................................17Treatments Without Escape Extinction ........................................................................... 182 FUNCTIONAL ANALYSIS OF PROBLEM BEHAVIOR ..................................................22Method ........................................................................................................................ ............22Subjects and Setting ........................................................................................................22Response Measurement and Reliability .......................................................................... 22Procedures .................................................................................................................... ...24Results .....................................................................................................................................263 STUDY 1: EFFECTS OF NEGATIVE REINFORCEMENT MAGNITUDE ...................... 28Method ........................................................................................................................ ............28Subjects and Setting ........................................................................................................28Response Measurement and Reliability .......................................................................... 28Procedures .................................................................................................................... ...29Experimental Design ....................................................................................................... 30Results .....................................................................................................................................31

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6 4 STUDY 2: EFFECTS OF NEGATIVE REINFORCEMENT QUALITY ............................. 37Method ........................................................................................................................ ............37Subjects and Setting ........................................................................................................37Response Measurement and Reliability .......................................................................... 37Procedures .................................................................................................................... ...39Experimental Design ....................................................................................................... 40Results .....................................................................................................................................405 DISCUSSION .................................................................................................................... .....43LIST OF REFERENCES ...............................................................................................................57BIOGRAPHICAL SKETCH .........................................................................................................63

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7 LIST OF TABLES Table page 2-1 Subject characteristics ................................................................................................... .....533-1 Task demands included for each subject in Study 1 .......................................................... 543-2 Means and ranges of dependent measures for each subject Study 1 ................................. 554-1 Task demands included for each subject in Study 2 .......................................................... 564-2 Means and ranges of dependent measures for each subject Study 2 ................................. 56

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8 LIST OF FIGURES Figure page 2-1 Functional analysis results for Emma, Braxton, Tim, Gary, John, Rita, Keith, Ethan, and Kendra. ........................................................................................................................273-1 Treatment results for Emma and Braxton in Study 1. ....................................................... 343-2 Treatment results for Tim in Study 1. ................................................................................ 353-3 Treatment results for Gary, J ohn, Rita, and Keith in Study 1. ...........................................364-1 Treatment results for Ethan, Keith, and Kendra in Study 2. .............................................. 42

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9 LIST OF ABBREVIATIONS FA Functional analysis SIB Self-injurious behavior EO Establishing operation NCR Noncontingent reinforcement NCE Noncontingent escape EXT Extinction DRA Differential reinforcement of alternative behavior DRO Differential reinforcement of other behavior DNRA Differential negative reinforcement of alternative behavior DNRO Differential negative reinfo rcement of other behavior HP High preferred RPM Responses per minute SrNegative reinforcement Sr+ Positive reinforcement BL Baseline PD Property destruction Mag Magnitude LQ Low quality MR Mental retardation

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10 Abstract of Dissertation Pres ented to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy COMPETING CONTINGENCIES FOR ESCAPE BEHAVIOR: EFFECTS OF NEGATIVE REINFORCEMENT MAGNITUDE AND QUALITY By Jennifer L. Hammond August 2009 Chair: Brian A. Iwata Major: Psychology Previous research has shown that proble m behavior maintained by social-negative reinforcement can be treated without escape extinction by enhancing the quality of positive reinforcement for an appropriate alternative resp onse such as compliance. By contrast, negative reinforcement (escape) for compliance generally has been ineffective in the absence of extinction. It is possible, howev er, that escape for compliance might be effective if the magnitude or quality of negative reinforcement for compliance is greater than that for problem behavior. This study examined the effects of negative reinforcement magnitude and quality on problem behavior and compliance that occurred in th e context of demands. In Study 1, we evaluated the effects of negative reinforcement magnitude on the escape-maintained behavior of 7 individuals with developmental disabilities. Across all treatment phases, compliance produced escape of an equal, greater, or (in some cases) lesser duration than problem behavior. Problem behavior decreased for 2 of 7 subjects when eq ual magnitudes of reinforcement were delivered for both response options. One subject demonstr ated reductions in problem behavior and improvements in compliance in the absence of escape extinction when compliance was positively reinforced. The remaining 4 subjects, however, showed no improvement until extinction was added as a treatment component. In Study 2, we evaluated the effects of negative

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11 reinforcement quality on the escape-maintained behavior of 3 individuals by blocking problem behavior for the duration of its occurrence duri ng the escape interval. Treatment effects were achieved for 2 of 3 subjects when the quality of negative reinforcement was manipulated. Enhancing the quality of positive reinforcement for compliance was required for the remaining subject. Taken together, result s suggest that (a) very small breaks following problem behavior may be sufficient to maintain behavior that is sensitive to escape as a reinforcer, but that (b) reducing the quality of negativ e reinforcement for problem be havior via blocking may be effective even though task demands ar e removed for a period of time.

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12 CHAPTER 1 INTRODUCTION Functional Analysis of Problem Behavior Functional analysis m ethodology is the benchm ark standard for assessment in applied behavior analysis (cf. Hanl ey, Iwata, & McCord, 2003; Iwat a, Kahng, Wallace, & Lindberg, 2000). This experimental approach identifies en vironmental variables that maintain problem behavior through the systematic manipulation of antecedent and consequent events that are known to influence behavior. Thus, a functional an alysis aims to recreate the conditions under which problem behavior is likely to occur. Th is series of studies focuses on the functional analysis and treatment of problem behavior that occurs in the context of instructional demands. Iwata, Dorsey, Slifer, Bauman, and Richman (1982/1994) were the first to demonstrate the utility of functional analysis (FA) methodology in elucidating both the social and nonsocial sources of reinforcement that may maintain pr oblem behavior exhibite d by individuals with developmental disabilities. They created a seri es of three test conditions and one control condition, which were alternated rapidly in a mu ltielement design. The test conditions included: alone (the subject was in a ba rren environment, and no programmed consequences were placed on problem behavior; this condition tested for ma intenance by automatic reinforcement), social disapproval (no attention was provided to the subj ect except contingent on problem behavior; this condition tested for maintenance by social-positive reinforcement), and academic demand (instructions were presented on a fixed-time schedule and were removed contingent on problem behavior only; this condition tested for mainte nance by social-negative reinforcement). A play condition served as the control, in which the subject had nonconti ngent access to preferred items and social interaction; the purpose of this cond ition was to nullify test components of the other conditions. Differential responding in one or more test conditions indicated the source of

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13 reinforcement that maintained problem behavior, and Iwata et al. demonstrated that the selfinjurious behavior (SIB) of 6 of 9 subjects wa s reliably associated with a specific stimulus condition, thus, empirically supporting early hypo theses (e.g., Carr, 1977; Smolev, 1971) that such problem behavior could be main tained by operant contingencies. Function-Based Treatment Selection Although Iwata et al. (1982/1994) noted the im plications of their findings for assessment and treatment, the full scope of FA methodology has become more apparent in the years since its original publication. The procedures have been replicated in hundr eds of studies across various populations, settings, and topographies of probl em behavior (see Hanley et al., 2003, for a discussion). Furthermore, the use of FA me thodology has been cited as a prime factor contributing to a decrease in the use of puni shment (Pelios, Morren, Tesch, & Axelrod, 1999), government regulations specifying best practice (e.g., Individuals with Disabilities Educational Act; IDEA, 1997), and the development of more effective treatments overall. Perhaps the most pragmatic feature of FA met hodology is that it can be used to guide the selection of treatments based on principles of reinforcement to yield the most efficient and effective outcomes. Prior to th e use of FA methodology, reinforcem ent-based interventions often were applied haphazardly based on ones best gu ess as to what approach might prove most effective. Because the success of such arbitrary approaches to treatmen t selection often hinged on the ability of the programmed reinforcer to compete with the behaviors maintaining contingency, these early attempts at treatment sometimes failed or were less effective than procedures based on punish ment (e.g., Cataldo, 1991). A number of function-based treatments that center on principles of reinforcement have been identified over the past 20 years (cf. Iwata, Vollmer, Zarcone, & Rodgers, 1993). These procedures are best classified according to th eir underlying behavioral processes. Problem

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14 behavior can be suppressed thr ough: (a) eliminating the relevant establishing operation or EO that influences the val ue of a reinforcer (noncontingent reinforcement), (b) eliminating the maintaining contingency (extinction), and (c) strengthening a competing response (differential reinforcement). These general strategies are common across problem behavior, although procedural differences arise based on the source of reinforcement that maintains a particular behavior. Treatment of Problem Behavior Maintained by Escape Social-negative reinforcem ent plays a promin ent role in the maintenance of problem behavior (cf. Iwata, 1987). Epid emiological studies indicate that avoidance of or escape from task demands may account for the largest propor tion of problem behavior shown by individuals with developmental disabilitie s roughly 40% (Derby et al., 1992; Iwata et al., 1994b). Therefore, an understanding of the role that ne gative reinforcement plays in the development and maintenance of problem behavior is important to the development of effective treatment. A number of reinforcement-based treatments for escape-maintained behavior have been developed over the years (see Ci pani & Spooner, 1997, for a review). These procedures are best classified according to the three fundamental approaches noted previously, namely: noncontingent reinforcement (EO ma nipulations), extinction, and differential reinforcement. Noncontingent Reinforcement Noncontingent reinforcem ent (NCR) decreases behavior by eliminating the EOs that make behavior reinforcing in the first place. In ty pical application, NCR invol ves the delivery of the consequence that is responsibl e for behavioral maintenance ac cording to a time-based schedule (see Carr et al., 2000, for a review). For problem behavior maintain ed by negative reinforcement, this may mean that escape (a break from work ) is delivered frequently in a demand context, irrespective of the s ubjects behavior (NCE; e.g., Vo llmer, Marcus, & Ringdahl, 1995).

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15 Alternatively, noncontingent access to positive reinforcers during instru ctional trials also has been used to treat escape-maintained behavi or. For example, Wilder, Normand, and Atwell (2005) found that 1 subjects se lf-injury and food refusal decreased when she was given noncontingent access to preferred videos dur ing feeding sessions Another antecedent intervention that has been shown to reduce proble m behavior maintained by escape is stimulus fading, in which the difficulty (e.g., Weeks & Ga ylord-Ross, 1981) or frequency (e.g., Pace, Iwata, Cowdery, Andree, & McIntyre, 1993; P ace, Ivancic, & Jefferson, 1994) of the task initially is reduced to the point where problem behavior no longer is evok ed, and then gradually increased to baseline levels while low rates of problem behavior are maintained. Finally, the high-probability instructional sequence or highp sequence involves presenting a series of instructions with which the subject is likely to comply immediately before an instruction with which the subject is not likely to comply the momentum of compliance generated by the highp responses is believed to facilitate respons e persistence in the face of changing conditions (i.e., lowp demands) (e.g., Mace & Belfiore, 1990). The common feature among all of these procedures is the alteration of an antecedent event that typically evokes problem behavior. Extinction Extinction (EXT) suppresses behavior by discontinuing the response-reinforcer relationship (Ferster & S kinner, 1957). Identifica tion of the behaviors maintaining contingency, therefore, is a prerequisite for the effective use of EXT (Iwata, Pace, Cowdery, & Miltenberger, 1994a). For problem behavior maintained by negative reinforcement, EXT involves continued presentation of demands and prevention of es cape contingent on the occurrence of problem behavior (Iwata, Pace, Kalsher, Cowdery, & Ca taldo, 1990). Iwata et al. (1990) found that the escape-maintained SIB of 5 of 6 individuals with developmental disabilities rapidly decreased when problem behavior no longer produced a break, and also observed concomitant

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16 improvements in the subjects compliance even though the contingencies for compliance remained unchanged. These effects have been replicated in numerous studies, and escape EXT may well be regarded as the most effective and efficient method of decreasing problem behavior that occurs in the context of de mands (cf. Iwata, 1987). In short, it is a key component of many behavioral procedures (e.g., NCR, differential re inforcement, as well as punishment), and the effectiveness of these procedures may be a f unction solely of EXT (see Lerman & Iwata, 1996b, for a review). Differential Reinforcement Dif ferential reinforcement, including differen tial reinforcement of alternative behavior (DRA) and differential reinforcement of other be havior (DRO), suppresses problem behavior by strengthening a competing response or some feat ure of a response, such as longer inter-response times in the case of DRO (see Vollmer, 1999, for a discussion). Differential reinforcement for escape-maintained behavior may take one of several forms. First, negative reinforcement may be delivered contingent on an appropriate alternat ive response (DNRA). For example, escape from task demands for a period of time may be deliv ered contingent upon a request for a break (e.g., finished; Marcus & Vollmer, 1995); similarly, av ersive characteristics of the task may be reduced contingent on an appropriate request for assistance (e.g., help; Carr & Durand, 1985). Alternatively, escape may be provided contingent on compliance (Marcus & Vollmer). By contrast, DRA for escape-maintained behavior ma y include delivering potent positive reinforcers (e.g., preferred edible items or toys) contingent on an appropriate alternative response, such as compliance (DeLeon, Neidert, Ande rs, & Rodriguez-Catter, 2001; La lli et al., 1999; Piazza et al., 1997). Finally, differential negative reinforcement of other behavior (DNRO) involves providing escape from task demands contingent on the omission of problem behavior for a period of time (e.g., Kodak, Miltenberger, & Romaniuk, 2003; Vollm er et al., 1995). Collectively, results of

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17 these studies have shown that, when reinforcement is delivered contingent on some characteristic of behavior other than the target problem behavior, a decrease in that problem behavior typically is observed (see Vollmer & Iwata, 1992, for a ge neral review of differential reinforcement procedures). It is important to note that diffe rential reinforcement almost always includes an EXT component, which eliminates the possibility that problem behavior might compete with alternative behavior. Treatment With Escape Extinction Although the interventions described above have been found to be extremely effective in treating behavior that occurs in the context of dem ands, most share one common element that may be partially or wholly responsible for observed treatment effects namely, the use of EXT. Most research has shown that EXT is a criti cal component of treatment (Mazaleski, Iwata, Vollmer, Zarcone, & Smith, 1993; Zarcone, Iwata, Hughes, & Vollmer, 1993; Zarcone, Iwata, Mazaleski, & Smith, 1994; Zarcone, Iwata, Smith, Mazaleski, & Lerman, 1994). For example, in a series of studies, Zarcone et al. demonstrated that escape EXT contribu ted to the success of the highp instructional sequence and demand fading pr ocedures, and that (in some cases) EXT alone was sufficient to suppress problem behavi or and increase compliance (e.g., Zarcone et al., 1993). Despite the fact that EXT is a highly effective treatment, adverse side effects such as bursting (a temporary increase in responding) or EXT-induced aggr ession have been observed occasionally, which may preclude its use in applie d settings (Goh & Iwata, 1994; Lerman, Iwata, & Wallace, 1999). Moreover, the severity of problem behavior or the size of the individual who exhibits it may prevent the use of EXT for es cape-maintained behavior. That is, because EXT requires the continued presentation of demands and prevention of escape, which also may require physical intervention, it may not be feasible w ith large or combative individuals. Thus, an

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18 important treatment consideration is whether it is possible to decrease problem behavior maintained by escape without EXT. Treatments Without Escape Extinction Results of som e studies have suggested that antecedent interventions such as demand fading (Pace et al., 1994) and act ivity choice (Romaniuk et al., 2002), as well as consequent interventions such as DRA (Horner & Day, 1991; Lalli, et al., 1999; Piazza et al., 1997), might be effective even when escape-maintained behavior continues to be negatively reinforced with greater emphasis being placed on DRA. Although most research on DRA for escape-maintained behavior has incorporated EXT, several studi es have shown that DR A without EXT may be effective when qualitatively different reinforcers are used. For example, positive reinforcement for compliance, either alone (e.g., an edible item; DeLeon et al., 2001; Lalli et al.) or combined with negative reinforcement (e.g., access to preferred ac tivities and/or attention during the escape interval; Hoch, McComas, Thompson, & Pa one, 2002; Lalli & Casey, 1996; McComas, Goddard, & Hoch, 2002; Piazza et al.) has been shown to reduce escape-maintained behavior without EXT. Because the contingencies arranged in these studies involved different reinforcers (i.e., positive reinforcemen t for compliance versus negative re inforcement for problem behavior), these arrangements can best be described as un equal or asymmetrical (s ee Fisher & Mazur, 1997, for a discussion). Several studies also have examined whethe r negative reinforcement (alone) for an appropriate alternative response may compete with problem behavior maintained by escape in the absence of EXT. Because th e contingencies arranged in thes e studies involved qualitatively similar reinforcers (negative reinforcement for both compliance and problem behavior), these arrangements incorporate equa l outcomes. Although the major ity of studies have shown negligible effects when escape for appropriate and problem behavior was equivalent (DeLeon et

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19 al., 2001; Hoch et al., 2002; Lalli et al., 1999), resu lts of some studies have suggested that escape for an appropriate alternative response may compete with escape for problem behavior. For example, Piazza et al. (1997) found that the esca pe-maintained problem behavior of 1 of 3 subjects eventually decreased to zero when both compliance and problem behavior produced equal durations of negative reinforcement. Sim ilarly, Horner and Day (1991) found that escape for an appropriate alternative response produ ced both reductions in problem behavior and improvements in the alternative response when the alternative re sponse (mand) was either more efficient or reinforced more frequently than the target response. In general, however, idiosyncratic results have been obtained in st udies evaluating the effects of DNRA on escapemaintained behavior when equa l outcomes are incorporated. One method that might enhance the effects of negative reinforcement for compliance would be to increase the magnitude (duration) of escape for appropria te behavior relative to that for problem behavior. Some applied research has shown that increas ing the magnitude of positive reinforcement may decrease behavior that is maintained by access to tangible items. For example, Carr, Bailey, Ecott, Lucker, and We il (1998) obtained lower ra tes of responding when a relatively large amount of food was deliver ed noncontingently (i.e., in the NCR-high condition), whereas baseline rates of responding were obtained when smaller amounts of food were delivered in the NCR-low condition. Ro scoe, Iwata, and Rand (2003) extended these findings by showing that larger magnitudes of re inforcement, defined functionally based on rates of responding during contingent reinforcement, can reduce response rates under NCR even when session time is corrected to account for reinforcer consumption time. Lerman, Kelley, Van Camp, and Roane (1999) also showed that DRA + EXT produced consistently lower levels of

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20 problem behavior when a functi onally equivalent alternative response resulted in a longer duration of access to the putativ e reinforcer (i.e., toys). Although magnitude has been shown to be a so mewhat influential parameter for behavior maintained by positive reinforcement, the effect s of negative reinforcement magnitude are less certain. Very little applied research has been conducted on the effects of negative reinforcement magnitude. A notable exception is a study by Lerman, Kelley, Vorndran, Kuhn, and LaRue (2002), who examined the effects of reinforcement magnitude on the appropriate communication of 3 subjects whose problem behavior was placed on EXT throughout the evaluation. For subjects whose problem behavior was maintained (at least in part) by escape from task demands, the duration of escape delivered contingent on appropriate communicatio n was varied. Results generally showed that the subjec ts rates of communication were similar across the 20-, 60-, and 300-s magnitude conditions, thus suggesting that ne gative reinforcement magnitude may not be a major determinant of behavior. It is possible, ho wever, that the single reinforcement schedule for appropriate behavior, in whic h only one magnitude was availa ble in a given experimental condition, partially contributed to the negative resu lts obtained. It has been noted that concurrent schedules, in which different pa rameters are compared directly by making both available but for different responses, are better suit ed to examine the relative eff ects of reinforcement magnitude (cf., Catania, 1963). Additionally, because prob lem behavior was placed on EXT throughout the evaluation, the relative effects of negative reinforcement magnitude on problem behavior maintained by escape remain unknown. It is also possible that escape-maintained behavior could be treated without EXT by altering qualitative characteristics of negative reinforcement. Most research on competing contingencies for behavior ha s shown that the quality of positive reinforcement is a highly

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21 influential determinant of reinforcement effect s (e.g., Kodak et al., 2007; Lalli et al., 1999; Mace, Neef, Shade, & Mauro, 1996; Neef, Mace, Shea, & Shade, 1992; Neef, Shade, & Miller, 1994). However, it remains unknown whether negative reinforcement quality would prove to be an equally powerful parameter. One way its effects could be evaluated would be to block problem behavior for the duration of its occurrence, which might reduce the quality of reinforcement because escape is available only to the extent that blocking is in effect. Thus, reductions in problem behavior might be obtai ned even though problem behavior continues to produce escape on some level. This question has direct clinical relevance because the severity of the behavior (i.e., SIB or aggression) sometimes necessitates immediate inte rvention to ensure the safety of the individual or others. Surpri singly, very little research ha s been conducted in this area. A notable exception is a study by Peck et al. (1996), who found that the escape-maintained problem behavior of 2 subjects decrea sed when problem behavior was blocked; however, because both the magnitude of negative reinforcement and qual ity of positive reinforcement associated with the appropriate alternative respons e also were enhanced in this study, the effects of blocking per se on problem behavior mainta ined by escape remain unknown. In summary, although the majority of a pplied research suggests that negative reinforcement (alone) for compliance is ineff ective in reducing escape-maintained problem behavior without EXT, additional research is wa rranted. That is, little research been conducted on methods for strengthening negative reinforcement for appropriate behavior relative to that for problem behavior. The purpose of this study ther efore is to determine whether increases in compliance and decreases in escape-maintained problem behavior may be obtained when the magnitude or quality of negative reinforcement for problem behavior is lessened relative to that for compliance.

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22 CHAPTER 2 FUNCTIONAL ANALYSIS OF PROBLEM BEHAVIOR Method Subjects and Setting Nine individuals diagnosed with developm en tal disabilities who were referred for assessment and treatment of problem behavior part icipated. Subject characteristics are listed in Table 2-1. Functional analyses we re conducted initially as a sc reening procedure to identify subjects whose problem behavior was maintained by escape from task demands. Sessions were conducted in a self-contained clas sroom at a special education sc hool or in an observation room at an adult day program. Session areas contained a table and chairs, as well as materials that varied according to the condition in effect. Setting and room characteristics remained the same across Studies 1 and 2. Sessions were 10 min in duration; 1 to 5 sessions were conducted each day, and sessions typically were conducted 2 to 5 days per week depending on the subjects schedules. Response Measurement and Reliability The prim ary dependent measure was the num ber of responses per minute of problem behavior. Topographies of probl em behavior included property destruction (Emma, Tim, John, and Keith), self-injury (Bra xton and Kendra), and aggressi on (Gary, Rita, and Ethan). Operational definitions of the target problem behaviors for each subject are listed in Table 2-1. Data also were collected on the subjects comp liance with demands (Emma, Braxton, Tim, John, Rita, and Ethan), which was defined as completion of the task following either a verbal or model prompt. Several therapist behaviors also were reco rded. Attention delivery was defined as the therapist initiating verbal or phys ical interaction with the subject A prompt was defined as the

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23 initial instruction in a threestep sequence. Escape was define d as the therapist terminating demands and turning away from the subject fo r 30 s. Tangible was defined as the therapist handing the subject an item or placing an item directly within reach of the subject. Observers recorded the frequency of subject target problem behavior, subject compliance, and therapist behavior during continuous 10s intervals using a handheld Palm PDA. Interobserver agreement was assessed by ha ving a second observer simultaneously but independently collect data during at least 25% of the FA sessions for all subjects. Proportional agreement percentages were calculated for each response by comparing the two observers recorded frequencies during each 10-s interval. The smaller number of responses was divided by the larger number in each interval with a disagreement, the fractions were summed across all intervals, and the total was adde d to the total number of agreement intervals in the session. The sum was divided by the total number of intervals in the session and multiplied by 100% to yield reliability scores for each dependent measure. M ean reliability scores were as follows: Emma, 94.5% for property destruction (range, 84.2% to 100%), 96.7% for compliance (range, 93.3% to 100%), and 94.4% for therapist behaviors (range 90% to 100%); Braxton, 100% for SIB, 100% for compliance, and 97% for therapist beha viors (range, 89.2% to 100%); Tim, 97.1% for property destruction (range, 88.5% to 100%), 96. 7% for compliance, and 91.7% for therapist behaviors (range, 80% to 100%); Gary, 99.8% for aggression (range, 99.2% to 100%) and 97.5% for therapist behaviors (range, 93.3% to 100%); John, 100% for property destruction, 100% for compliance, and 97% for therapist behaviors (ra nge, 90% to 100%); Rita, 96.1% for aggression (range, 95% to 100%), 100% for compliance, and 96.9% for therapist behaviors (range, 93.3% to 100%); Keith, 99.5% for property destruction (range, 96.7% to 100%) and 100% for therapist behaviors; Ethan, 98.5% for aggression (range, 94.2% to 100%), 96.7% for compliance, and

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24 93.5% for therapist behaviors (range, 73.3% to 100%); and Kendra, 100% for SIB and 100% for therapist behaviors. Procedures FAs were conducted using procedures sim ilar to those described by Iwata et al. (1982/1994). Test and co ntrol conditions were alternated in a multielement design. Attention, play, and demand conditions were included in all FAs. An ignore condition generally was not included if the target respons e was aggression, and a tangible condition was conducted only if caregiver report suggested that problem behavior might be maintained by access to preferred items or activities. Specific stimuli (e.g., different therapists, session areas, or colored shirts) were associated with each FA condition to enhanc e discrimination of the contingencies in effect (Conners et al., 2000). Ignore: The purpose of this condition was to dete rmine if problem behavior would persist in the absence of social contingencies, suggesting that problem behavior was maintained by nonsocial (automatic) reinforcement. The subject was in an isolated area of the room without access to leisure items or social interaction. The th erapist also was present but did not interact in any way with the subject throughout the session. Attention: The purpose of this condition was to determine if problem behavior was maintained by social-positive reinforcement in th e form of attention. The subject had access to 23 moderately preferred toys identified via a pa ired-stimulus (Fisher et al., 1992) or a multiplestimulus (DeLeon & Iwata, 1996) preference assessm ent. At the start of the session, the therapist told the subject, I have some work to do, but you can play with these toys if youd like. The therapist sat next to but did not interact w ith the subject. Continge nt upon each occurrence of target problem behavior, however, the therapist delivered a brief reprimand and statement of

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25 concern (e.g., You shouldnt do th at; youre going to hurt your self!) and ge ntle physical contact (e.g., placed a hand on the subjects arm). Tangible: The purpose of this condition was to determine if problem behavior was maintained by social-positive reinforcement in the form of access to preferred items. The subject was given approximately 60-s access to 3 high-pr eferred (HP) edible items (identified in a preference assessment) immediately before the start of the session. At the start of the session, the therapist removed the it ems from the subject but remained nearby. If the subject initiated interaction with the ther apist during this conditio n, the therapist briefly responded to the subject and then terminated the interaction (e.g., quickly an swered a question or said Well talk later.). Contingent on the occurrence of problem behavi or, one small edible item was delivered. Demand: The purpose of this condition was to determine if problem behavior was maintained by social-negative reinforcement in the form of escape from task demands. The subject was seated at a table w ith task materials present. The therapist initiated academic or vocational trials on a fixed-time 30-s schedule us ing a graduated, three-step prompt sequence (verbal instruction, model prompt, physical guidance at 5-s intervals if compliance did not occur). Contingent on compliance, the therapist delivered verbal praise and began a new trial. Contingent on problem behavior, the therapist discontinued the demands and moved away from the subject for 30 s. Play: This condition served as the control c ondition in which antecedent and consequent events likely to occasion problem behavior were absent. The subject and therapist were seated at a table or on the floor. The subject had continuous access to 2-4 HP leisure items (identified in a preference assessment), and the therapist initiated friendly in teraction with the subject approximately every 30 s (contingent upon a 5-s ab sence of problem behavior) or any time the

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26 subject initiated appropriate interaction. No consequences were delivered following the occurrence of problem behavior. Results Figure 2-1 s hows results of the FAs for each su bject who participated in Studies 1 and 2. Emma, Braxton, Tim, Gary, John, Ri ta, and Keith engaged in higher rates of problem behavior in the demand condition and little or no problem be havior in any other c ondition, indicating that their problem behaviors were maintained by escape from task demands. Ethan and Kendra also engaged in high rates of problem behavior in the demand condition. However, their problem behavior occurred at so mewhat similar rates in the tangible condition. Thus, Ethans aggression and Kendras hand biting a ppeared to be maintained not only by escape from task demands but also by access to preferred edible items. Taken together, data for all subjects indicate that their problem behaviors were maintained (at least in part) by social-nega tive reinforcement, which was a prerequisite for participation in the treatment phases of this study.

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27 Figure 2-1. Functional analysis results for all subjects. Emma, Braxton, Tim, Gary, John, Rita, and Keith participated in Study 1; Keith, Ethan, and Kendra participated in Study 2.

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28 CHAPTER 3 STUDY 1: EFFECTS OF NEGATIVE REINFORCEMENT MAGNITUDE Method Subjects and Setting Emm a, Braxton, Tim, Gary, John, Rita, and Ke ith participated in Study 1. Sessions were 10 min in duration; 1 to 8 sessions were c onducted each day, and sessions typically were conducted 2 to 5 days per week depending on the subjects schedules. Response Measurement and Reliability The prim ary dependent measure was the num ber of responses per minute of problem behavior (see Table 2-1 for definitions). Data also were collected on subjects compliance with demands, as previously defined. The demands include d for each subject are listed in Table 3-1. The frequency of therapist behavior, including initial verbal instructions and reinforcer delivery (i.e., escape and edible item, if applicable) was recorded. Additionally, data were collected on reinforcer consumption time (the duration of the escape interval), which was subtracted from session time, yielding a conservative estimate of the rate of problem behavior that was not artificially suppre ssed merely as a function of redu ced time spent in the presence of demands. Interobserver agreement was calculated as previously described. Mean reliability scores were as follows: Emma, 96.6% for property destruction (range, 86.6% to 100%), 97% for compliance (range, 93.3% to 100%), 92.2% for therapist instructions (r ange, 84.2% to 100%), and 98% for therapist reinforcer delivery (range, 91.6% to 100%); Braxton, 98.9% for SIB (range, 92.5% to 100%), 98.6% for compliance (range, 90.3% to 100%), 93.4% for therapist instructions (range, 85% to 100%), and 95.9% for therapist reinfor cer delivery (range, 55% to 100%); Tim, 97.7% for property destruction (range, 86.5% to 100%), 96.7% for compliance

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29 (range, 90% to 100%), 97.1% for therapist inst ructions (range, 87.8% to 100%), and 97% for therapist reinforcer deliv ery (range, 86.7% to 100%); Gary, 96.8% aggressi on (range, 87.5% to 100%), 96.1% for compliance (range, 84.1% to 100 %), 93.3% for therapist instructions (range, 79.9% to 100%), and 94.7% for therapist rein forcer delivery (range, 82.5% to 100%); John, 96.1% for property destruction (range, 87.5% to 100%), 98% for compliance (range, 90% to 100%), 91.9% for therapist inst ructions (range, 68.3% to 100 %), and 97.3% for therapist reinforcer delivery (range, 86.7% to 100%); Rita, 95.6% for aggression (range, 80.6% to 100%), 98.4% for compliance (range, 90% to 100%), 93.3% for therapist instructions (range, 79.2% to 100%), and 97.3% for therapist reinforcer deliv ery (range, 86.7% to 100%); and Keith, 94.4% for property destruction (range 81.7% to 100%), 97% for compliance (range, 79.2% to 100%), 95.7% for therapist instructions (range, 84.2% to 100%), and 96.7% for therapist reinforcer delivery (range, 89.2% to 100%). Procedures A concurrent-schedule arrangem ent, in which two or more response options are available to a subject, each associated with a different c onsequence (Catania, 1963), was used to evaluate the effects of negative reinforcement magnitude on compliance and on problem behavior. The magnitude (duration) of escape associated wi th compliance and/or problem behavior was systematically manipulated across conditions, such that (a) compliance did or did not produce a break (or access to posit ive reinforcement), and (b) problem behavior did or did not produce a break of equal, lesser, or (in some cases) grea ter magnitude than complia nce. The contingencies in effect were not described to the subjects at any time. Treatment condi tions are labeled with two symbols (e.g., Praise/ Sr-); the first symbol denotes the co nsequences for compliance, and the second symbol denotes the consequence for problem behavior.

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30 Baseline (Praise/ Sr-): Procedures were similar to the demand condition of the FA. Compliance resulted in verbal praise followed by resumption of task demands. Problem behavior produced 30-s escape. Equal Escape (Sr-/ Sr-): Procedures were similar to thos e used in baseline, except that compliance also produced a 30-s break. Enhanced Reinforcement Magnit ude for Compliance (Enhanced Sr-/ Sr-): Procedures will were similar to those used in the equal Sr-/ Srcondition, except that compliance now produced 120-s escape from the task, whereas pr oblem behavior conti nued to result in 30-s escape (i.e., 120/ 30). If this phase proved ine ffective, the magnitude of reinforcement for problem behavior was reduced, such that probl em behavior produced only 5-s escape (i.e., 120/ 5). Positive Reinforcement for Compliance (Sr+/ Sr-): Escape no longer was provided for compliance. Rather, contingent on compliance, one of three HP edible items was delivered in a varied format (Egel, 1981). Immediately follow ing the delivery of the HP edible item, the therapist instructed the subject to complete another task. Problem behavior continued to produce 30-s escape. Positive Reinforcement plus Extinction (Sr+/ EXT): Procedures were similar to those used in the previous Sr+/ Srphase, except that extinction (EXT) now was in effect for problem behavior. Contingent on the occurrence of probl em behavior, the therapist physically guided the subject to complete the task and then pres ented the next demand; no break was provided. Experimental Design Experim ental control was established by way of a multiple baseline across subjects (Emma and Braxton) or reversal designs (Tim, Gary, John, Rita, and Keith). The A condition consisted of baseline, the B condition consisted of equal Sr-/ Sr-, the C condition consisted of enhanced

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31 magnitude Sr-/ Sr(i.e., 120/ 30 or 120/ 5), the D condition consisted of Sr+/ Sr-, and the E condition will consisted of Sr+/ EXT. Treatment conditions were implemented sequentially, such that a given condition was implemented only af ter the previous condition was found to be ineffective. Results Table 3-2 su mmarizes means and ranges for subjects problem behavior and compliance across baseline and treatment conditions. Figur e 3-1 shows results for Emma and Braxton. Emma exhibited variable rates of property destruction and lo w levels of compliance during baseline. When the equal escape (Sr-/ Sr-) condition was implemented, her problem behavior decreased to near-zero rates, and her compliance increase d steadily across this condition. Braxton engaged in lower rates of problem be havior than did Emma during baseline. His compliance also was low but increased graduall y throughout the condition. Braxtons hand biting immediately decreased to zero rates when equal Sr-/ Srwas implemented; however, unlike Emma, his compliance improved very little. The enhanced reinforcement magnitude condition (enhanced mag Sr-/ Sr-) therefore was implemented in an effort to increase his compliance. However, increasing the relative magnitude of negative reinforcement for compliance from 30/ 30 to 120/ 30 was not an effective strategy for Braxton, as his compliance remained relatively unchanged from the previous condition. Because Br axton typically complied with the same two demands only (i.e., touch card, hand therapist card), it was concluded that additional teaching strategies rather than augmented amounts or qualities of reinforcement were necessary to further increase his compliance with the othe r tasks selected (i.e., touch [body part]). Tim (Figure 3-2) engaged in variable levels of property destructi on and compliance during baseline. The equal Sr-/ Srcondition did not produce clinically significant reductions in his problem behavior, although his compliance did improve. Similar results were obtained in the

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32 subsequent enhanced magnitude Sr-/ Srconditions (120/ 30 and 120/ 5), as both property destruction and compliance remained relativel y unchanged. When a preferred edible item was delivered contingent on compliance during the Sr+/ Srcondition, his property destruction quickly decreased and his compliance incr eased sharply, even though problem behavior continued to be negatively reinforced. When baseline was reinst ated, Tims problem behavior escalated to the highest rates obtained throughout the evaluation. When the Sr+/ Srcondition was reimplemented, treatment effects were replicated and maintained. Figure 3-3 shows results for Gary, John, Rita, and Keith. Although slight differences were seen in their rates of problem behavior and compliance during baseline and across subsequent conditions, all subjects showed the same ge neral pattern of responding. No significant improvements were observed in their behavior du ring either the equal or enhanced magnitude Sr-/ Srconditions. Similarly, the Sr+/ Srcondition had either negligib le effects on behavior (Gary, Rita, and Keith) or beneficial effects on complian ce but not on problem behavior (John). When the Sr+/ EXT condition was implemented, large reducti ons in problem behavi or were observed for all subjects, and improvements in complian ce were observed for 3 subjects (Rita was the exception). Following a return to baseline, thes e effects were replicated during the final Sr+/ EXT condition. In summary, 2 of 7 subjects (Emma and Br axton) exhibited reductions in problem behavior in the equal Sr-/ Srcondition; however, only 1 subjects (Emmas) compliance increased. Enhancing the magnitude of negative re inforcement for compliance, relative to that for problem behavior (enhanced mag Sr-/ Srcondition), was ineffective for all 6 subjects who were exposed to this condition. These results suggest that providing a break following problem behavior no matter how brief may be sufficient to maintain problem behavior that is sensitive

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33 to escape as a reinforcer as long as complian ce also produces escape. Providing a preferred edible item contingent on compliance while problem behavior continued to produce escape (Sr+/ Srcondition) was effective for only 1 of 5 subject s in this study. It appeared that, for Tim, positive reinforcement was a more potent reinforc er than negative reinforcement even though his problem behavior was maintained by escape. However, because we did not include a tangible condition in Tims FA, it remains unknown whether his property destruction also was maintained by access to preferred items. Finally, escape EX T was required to decrease the remaining 4 subjects problem behavior. Although not all subjects were exposed to EXT because it was implemented only if other procedures were ineff ective, the fact that a majority of subjects showed reliable improvements in behavior only wh en EXT was used were consistent with a great deal research showing rapid reducti ons in problem behavior during EXT.

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34 Figure 3-1. Treatment results for Emma and Brax ton in Study 1. (* The asterisk below Emmas compliance data point in the first equal Sr-/ Srsession [session #9] indicates that problem behavior is not plot ted; corrected rates could not be calculated due to a missing data stream.)

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35 Figure 3-2. Treatment results for Tim in Study 1.

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36 Figure 3-3. Treatment results for Gary, John, Rita, and Keith in Study 1.

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37 CHAPTER 4 STUDY 2: EFFECTS OF NEGATIVE REINFORCEMENT QUALITY Results of Study 1 suggested that enhancing the m agnitude of negative reinforcement for compliance may not be effective when problem be havior continues to produce escape, and that EXT may be necessary to reduce the problem behavi or of most subjects. However, as previously discussed, it may not always be possible for care givers to implement EXT for escape-maintained behavior. Given that reinforcement quality has been found to be an important determinant of reinforcement effects, it is possible that proble m behavior maintained by escape may be treated by reducing the quality of negative reinforcement av ailable for problem behavior relative to that for compliance. The purpose of Study 2, therefor e, was to examine the effects of negative reinforcement quality on problem behavior and on compliance when EXT is not used. Method Subjects and Setting Ethan, Keith, and Kendra participated in Study 2. Sessions were 10 m in in duration; 1 to 4 sessions were conducted each day, and sessions typi cally were conducted 2 to 5 days per week depending on the subjects schedules. Response Measurement and Reliability The prim ary dependent measure was the num ber of responses per minute of problem behavior (see Table 2-1 for definitions). Attempts to engage in the target problem behavior also were recorded during conditions that included response blocking. Et hans attempts to engage in aggression were defined as rais ing or swinging his hand, arm, or leg in the direction of the therapist; placing his mouth within 1 inch of the therapist; and rapidly moving his body within 6 inches of the therapist. Keiths attempts to engage in property destruction were defined as picking up an item and raising his forearm (contai ning the item) to a 45-degree angle or more,

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38 placing his thumb and one or more fingers at the t op of a sheet of paper in such a manner that the paper could tear if he rotated his fingers in oppos ite directions, reaching his hand within 6 inches of a wall containing paper, or swinging his ha nd or arm within 6 inches of an item (e.g., furniture) in a rapid and forward motion. Kendras attempts to engage in SIB were defined as placing her mouth within 6 inches of her palm. Da ta also were collected on subjects compliance, as previously defined. The demands included for each subject are listed in Table 4-1. The frequency of therapist verbal instruction, reinforcer delivery (i .e., escape and edible item, if applicable), and response blocking onset and offset also was recorded. Additionally, because escape and blocking periods were not al ways equal, duration data on these measures were recorded. As in Study 1, reinforcer c onsumption time during the escape intervals was subtracted from session time when calculating response rates, although bl ocked responses were included in the corrected response rates. Interobserver agreement was calculated as previously described. Mean reliability scores were as follows: Ethan, 96.5% for aggression (range, 85.9% to 100%), 96.8% for compliance (range, 90% to 100%), 94.5% for therapist in structions (range, 83.3% to 100%), 95.6% for reinforcer delivery (range, 86.7% to 100%), 99. 1% for blocking onset (range, 95.8% to 100%), and 98.4% for blocking offset (range, 90.8% to 1 00%); Keith, 97% for property destruction (range, 82.5% to 100%), 97.9% for compliance (range, 90% to 100%), 96% for therapist instructions (range, 88.3% to 100% ), 96.3% for reinforcer delivery (range, 86.7% to 100%), 97.9% for blocking onset (range, 86.7% to 100%), and 98.8% for blocking offset (range, 95% to 100%); and Kendra, 97.1% for SIB (range, 86.4% to 100%), 95.4% for compliance (range, 71% to 100%), 95.3% for therapist in structions (range, 80.6% to 100%), 95.0% for reinforcer delivery

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39 (range, 80.4% to 100%), 98.8% for blocking onset (range, 91.7% to 100%), and 99.4% for blocking offset (range, 93.3% to 100%). Procedures A concurren t schedule was used to evaluate the effects of negative reinforcement quality on compliance and on problem behavior. Across a ll phases, problem behavior produced escape from the task demands, whereas compliance did or did not result in escape. As in Study 1, treatment conditions are labeled with two symbols; the first symbol denotes the consequences for compliance, and the second symbol denotes the consequence for problem behavior. Baseline (Praise/ Sr-): Procedures were similar to the demand condition of the FA. Compliance resulted in brief ve rbal praise followed by anothe r task demand. Problem behavior produced 30-s escape. Equal Escape (Sr-/ Sr-): Procedures were similar to those used in baseline, except that compliance also produced a 30-s break. Low Quality (LQ) Negative Reinforcement for Problem Behavior (Sr-/ LQ Sr-): Compliance continued to produce 30s escape. However, attempts to engage in problem behavior now were blocked by briefly interrupting the response with the mini mum amount of contact necessary to prevent problem behavior. Positive Reinforcement for Compliance and LQ Negative Reinforcement for Problem Behavior (Sr+/ LQ Sr-): This condition was similar to the previous Sr-/ LQ Srcondition, except that an HP edible item now was delivered contingent on compliance (i.e., no break was delivered). Problem behavior continued to be bloc ked for the duration of its occurrence, as in the previous condition.

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40 Experimental Design A reversal design was used to establish experi m ental control. The A condition consisted of baseline, the B condition consisted of equal Sr-/ Sr-, the C condition consisted of Sr-/ LQ Sr-, and the D condition consisted of Sr+/ LQ Sr-. Treatment conditions were implemented sequentially, such that a given condition was implemented only after the previous condition was shown to be ineffective. Results Table 4-2 su mmarizes means and ranges for subjects problem behavior and compliance across baseline and treatment conditions. Figure 41 shows results for Ethan, Keith, and Kendra. The equal Sr-/ Srcondition produced no reliable decrease in problem behavior for any subject, although Kendras compliance improved somewhat When problem behavior was blocked (Sr-/ LQ Srcondition), Ethans and Keiths problem beha vior (attempts) decr eased to near-zero levels, and both subjects showed large increases in compliance. Following a return to baseline, these effects were replicated in a subsequent Sr-/ LQ Srcondition. Kendra showed a different pattern of results when blocking was implemented. Her rate of hand biting increased markedly during the Sr-/ LQ Srcondition. However, when a prefe rred edible item was delivered for compliance in the Sr+/ LQ Srcondition, Kendras hand biting immediately decreased to zero rates, and her task completion increased to near 100%. Following a return to baseline, treatment effects were replicated in the final S+/ LQ Srphase, as Kendra did not engage in any hand biting for several sessions, and she complied with the vast majority of task demands. In summary, 2 of 3 subjects (Ethan and Ke ith) showed immediate reductions in problem behavior when response blocking was implemented, even though it resulted in escape from task demands following problem behavior. Concomitant improvements in their compliance also were observed in this Sr-/ LQ Srcondition, even though the contingency for compliance remained

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41 unchanged. By contrast, Kendra only showed sustained improvements in problem behavior and compliance when compliance produced an appa rently more potent positive reinforcer (Sr+/ LQ Srcondition).

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42 Figure 4-1. Treatment results for Ethan, Keith, and Kendra in Study 2. (* The asterisk above Keiths data point for problem behavior in the first Sr-/ LQ Srsession [session #25] indicates that this session was terminated early [at 5-min].)

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43 CHAPTER 5 DISCUSSION The presen t studies examined the influence of quantitative and qualitative parameters of negative reinforcement on escape-maintained behavi or in the absence of EXT. The magnitude of escape for compliance (Study 1) and quality of escape for problem behavior (Study 2) were manipulated to determine their relative eff ects on compliance and problem behavior that occurred in the context of demands. Taken toge ther, results indicated that very small breaks following problem behavior may be sufficient to maintain problem behavior that is sensitive to escape as a reinforcer (Study 1), but that redu cing the quality of negative reinforcement for problem behavior via blocking may be effectiv e even though task demands contingently are removed for a period of time (Study 2). Results of Study 1 indicated that enhanci ng the magnitude (duration) of negative reinforcement for compliance, beyond that for pr oblem behavior, had littl e therapeutic effect when problem behavior conti nued to produce escape. Although 2 of 7 subjects (Emma and Braxton) demonstrated reductio ns in problem behavior when equal escape durations were available for both response options, the remain ing 5 subjects problem behavior failed to decrease even when the duration of escape for compliance was increased relative to that for problem behavior. These data indicate that nega tive reinforcement for compliance is unlikely to be effective without EXT, but if it is, relative magnitudes of escape for compliance versus problem behavior seem unimportant. These findings are consistent with both basic and applied research, which generally has shown inconsistent or complex relations between reinforcement magnitude and response rate (Reed, 1991; Reed & Wright, 1988; Trosclair-Lasserre, Lerman, Call, Addison, & Kodak, 2008), and further suggest that negative reinforcement magnitude may be a relatively weak paramete r of reinforcement (see Lerman et al., 2002, for a discussion).

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44 However, it is possible that addi tional (uncontrolled) features of the experiment contributed to the negative results obtained. Fo r example, although we includ ed only one-step tasks that required minimal response time, it is possible that if completing a task required more time than engaging in problem behavior, compliance with demands resulted in an increased delay to reinforcement. Given that reinfo rcer immediacy has been found to be a highly potent determinant of reinforcement effects (e.g., Neef, Mace, & Sh ade, 1993; Neef et al ., 2005; Rachlin, 1974), one might expects subjects to a llocate their responding toward the option that produced more immediate reinforcement in this case, problem behavior. Although most applied research in this area has evaluated parameters of positive reinforcement, a notable exception is a study by Solnick, Kannenberg, Eckerman, and Waller (19 80) who, using 90-dB white noise as the negative reinforcer, found that subjects preferre d briefer, more immediate escape (i.e., 90-s escape delivered immediately) ove r longer, more delayed escape (i.e., 120-s escape delivered after 60 s). In short, results of Study 1 extend the literature in suggesting that enhancing the magnitude of negative reinforcement for an appr opriate competing response (compliance) may not be effective when problem behavior maintain ed by escape continues to be reinforced. These results perhaps are not all that surprising. That is, because problem behavior continued to be negatively reinforced, subjects simply had to enga ge in more problem behavior in the enhanced reinforcement magnitude conditions to obtain si milar durations of escape (as was provided for compliance). The clinical implication of these negative findings is important because the delivery of a longer break following task completion is an obvious treatment strategy that one might consider when attempting to reduce proble m behavior that occurs in the context of demands. Although this strategy may seem reasonabl e, our data suggest that care providers

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45 should be cautious not to provide a break follo wing problem behavior no matter how brief particularly when compliance is negatively reinforced. Results of Study 1 also suggested that provi ding a preferred edible item contingent on compliance may not be effective in the absence of escape EXT. Four of 5 subjects continued to show baseline rates of problem behavior and (with the exception of John) compliance during the Sr+/ Srcondition. These results were unexpected and contradict those of previous research, which generally has shown positive reinforcement to compete quite well with negative reinforcement (i.e., Kodak, Lerman, Volkert, & Trosclair, 2007; Lall i et al., 1999). Several factors may have contributed to the negative resu lts obtained for the majority of our subjects in the Sr+/ Srcondition. First, as previously noted, it is possible that compliance was associated with a relative delay to reinforcement. For t hose subjects for whom immediacy was a more potent parameter of reinforcement (i.e., than quality), it would be expected that they would allocate their responding toward problem beha vior. Similarly, if compliance was the more effortful response, one might expect the subjects to allocate their re sponding toward problem behavior (cf. Horner & Day, 1991). Third, it is possible that positive reinforcement for compliance was ineffective because it was not a functional reinforcer for problem behavior. Some studies that have shown beneficial effects under the Sr+/ Srcontingency included subjects whose problem behaviors were maintained by both negative and positive reinforcement (i.e., DeLeon et al., 2001; Piazza et al., 1997); thus, pe rhaps it is not surprising that positive reinforcement for compliance was the superior treatment in these studies. However, because we did not include a tangible conditi on in the FAs of most of our s ubjects, we cannot conclude that their problem behaviors were not also sensitive to tangible reinforcement. Furthermore, because research has shown that positive reinforcemen t for compliance can compete with problem

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46 behavior that is maintained solely by escape (i.e., Lalli et al.), this interpretation seems unlikely. Fourth, the contingencies for comp liance were not described to any of our subjects, which is a procedural difference from studies showing that Sr+/ Srdecreased problem behavior maintained by escape only (i.e., Hoch et al., 2002; Lalli et al .). Additionally, it is re motely possible that the subjects lengthy history of escape for problem behavior biased their responding toward this alternative and contributed to the negative effects obtained in the Sr+/ Srcondition, as well as in the previous conditions wherein problem behavior continued to be negatively reinforced. Finally, escape EXT was necessary to decr ease the remaining 4 subjects problem behavior in Study 1. Given the ra pid reductions in problem behavi or that were achieved when EXT was implemented, results of Study 1 indicate d that (when possible) EXT should be used as the preferred method of treatment. These findings are supported by numerous studies that have shown that EXT may be a critical component of treatment (i.e., Mazaleski et al., 1993; Zarcone et al., 1993; 1994a; 1994b). Results of Study 2 suggested the possibility of altering a different di mension of negative reinforcement quality when EXT for problem behavior is not feasib le. Two subjects (Ethan and Keith) exhibited reductions in problem be havior when response blocking was implemented during the escape interval even though problem behavior also resu lted in the cessation of task demands for a period of time. These subjects also showed improvements in compliance when problem behavior was blocked during escape, despite the fact that the contingency for compliance remained unchanged. These results coinci de with previous research, which generally has shown that compliance improves without additional contingencies when problem behavior maintained by escape is decreased (Iwata et al., 1990). These findings perhaps raise the question as to what mechanism was responsible for the re duced rates of problem behavior obtained for

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47 both Ethan and Keith. Previous research on th e effects of response blocking on behavior maintained by automatic reinforcement suggests th at blocking may functi on as either punishment (Lerman & Iwata, 1996a) or EXT (Smith, Russo, & Le, 1999). It is possible that similar behavioral processes were responsible for the de creased rates of problem behavior observed for these subjects in the Sr-/ LQ Srcondition, particularly consideri ng that the quali ty manipulation involved a deterioration of conditions for problem behavior. Regardless, results for Ethan and Keith extend previous research (e.g., Peck et al ., 1996) in demonstrating that blocking (alone) may be an effective treatment for problem be havior maintained by negative reinforcement. Furthermore, these results perhaps suggest that negative reinforcement quality also may be an influential parameter. By contrast, Kendra exhibited a significant increase in problem behavior in the Sr-/ LQ Srcondition. Thus, blocking was not only ineffective for Kendra but in the absence of additional contingencies for compliance resulted in a wo rsening of problem behavior. Two factors may have contributed this. First, it is remotely possi ble that blocking someho w enhanced (rather than reduced) the quality of reinforcement that her hand biting produced in the Sr-/ LQ Srcondition. For example, anecdotal reports indicated that Kendra often laughed, smiled, and swayed her head back and forth (which she typically would do when playing) when blocking was implemented. Although the results of Kendras FA did not suggest an attention function, she did not contact the contingency for problem behavior in any of the attention sess ions (see Figure 2-1). Thus, although unlikely, perhaps her hand biting also was maintained by at tention, but that her FA (as configured) was not sensitive enough to capture th is function. A more probable explanation is that blocking, because of its aversive properties, elicited higher rates of problem behavior in the Sr-/ LQ Srcondition. Previous research has shown that aversive stimuli, when used as negative

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48 reinforcers, can acquire elic iting properties (Powell & P eck, 1969; Sidman, Herrnstein, & Conrad, 1957). Given the nature of Kendras problem behavior, however, it was not feasible to remove the blocking component because of the risk of self-harm that her hand biting posed. Therefore, positive reinforcement in the form of preferred edible items was delivered for compliance while problem behavior continued to be blocked. An immediate and sustained decrease in Kendras rate of hand biting was observed when the contingency for compliance was changed from negative to positive reinforcement. A marked increase in her level of compliance also was observed in this Sr+/ LQ Srcondition. Thus, contrary to the results of Study 1, Kendras results coincide with previous research, which largely has shown that problem behavior maintained (at least in part) by escape may be treated without EXT by delivering high quality positive reinforcers contingent on compliance (e. g., DeLeon et al., 2001; Lalli et al., 1999). Collectively, these results point to some di rections for future research on competing contingencies of negative reinforcement for beha vior that occurs in the context of demands. First, it is remotely possible th at the subjects lengthy history of escape for problem behavior rendered the enhanced reinforcement magnitude manipulation a very slow acting treatment, but one that might have been effective if given enough time. Future resear ch could examine this possibility by exposing the subjects to the e nhanced reinforcement magnitude condition for longer periods of time than they were in this study. Because treatment efficiency is an important consideration, however, th e utility of this approach may be questionable. Second, perhaps the magnitudes we used in this study were not suffici ently different to shif t the subjects response allocation from problem behavior to compliance. Additional res earch therefore could examine the effects of negative reinforcement magnit ude by providing considerably longer breaks contingent on compliance from the outset, relativ e to that for problem behavior. For example,

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49 sessions initially could be terminated following the first compliant response (e.g., resulting in a 9 min break or more if the subj ect complied immediately). As sustained improvements in the subjects behavior are demonstrated, the rate of task demands c ould be increased while relatively larger magnitude of negative reinforcement conti nue to be available for compliance. Such an approach would combine both antecedent (dema nd fading) and consequent (DRA) interventions. Although demand fading has been show n to be ineffective in the absence of EXT (Zarcone et al., 1994b), it is possible that treatment effects could be achieved by combining the two procedures. Similarly, perhaps delivering larger magnitudes of negative reinforcement for compliance would prove effective if used in conjunction with an er rorless learning or inst ructional fading procedure (Weeks & Gaylord-Ross, 1981). For example, diffic ult features of the task first could be removed by providing escape contingent on an appr opriate break request. This might reduce any delay to reinforcement that could be associated with compliance; if so, the subjects might be more likely to allocate their responding toward the appropriate response. If problem behavior decreases to low rates, difficult f eatures of the task could be reintroduced while the magnitude of escape for compliance is increased (as the contingency is changed from DRA [mand] to DRA [compliance]). Alternatively, future research could examine the relative effects of negative reinforcement magnitude on compliance and on pr oblem behavior following an EXT baseline. Previous research has shown that problem behavior might be treated without EXT by capitalizing on such sequence effects (e.g., Voll mer, Roane, Ringdahl, & Marcus, 1999). The clinical implications of this a pproach, if effective, would be th at sustained reductions in escapemaintained behavior might be achie ved in the relevant environment without EXT by first treating problem behavior with EXT in a clinic setting (i.e., with skilled therapists).

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50 Future research also could examine the c onditions under which positive reinforcement for compliance will and will not compete with prob lem behavior maintained by escape. Previous research has shown that the success of positive re inforcement is dependent on factors such as the subjects preference for the item that is delivere d contingent on compliance (i.e., highversus low-preferred items; Kodak et al., 2007) and the response requirements of the task itself (DeLeon et al., 2001). Results of Studies 1 and 2 extend these findings in suggesting that the quality of negative reinforcement that problem behavior pro duces also might influence the effectiveness of the Sr+/ Srprocedure. That is, when problem behavior produces escape in the absence of additional consequences (i.e., no blocking), Sr+ for compliance might be largely ineffective (Study 1); however, when the quality of escape for problem behavior is reduced via blocking, Sr+ for compliance may be rendered more effective (S tudy 2). Additional studies could evaluate the conditions under which Sr+/ Sris and is not an effective treatment for escape maintained behavior by examining the extent to which low rates of problem behavior are maintained under increasing schedule requirements for comp liance (e.g., Lalli et al., 1999) or when Sr+/ Sris implemented for longer periods of time (e.g., acro ss the school day). Also, future research perhaps could compare the utility of the Sr+/ Srprocedure at decreasing problem behavior that is maintained solely by escape versus problem behavior that is maintained by both negative and positive reinforcement. Additionally, it may be worth noting that our subjects differed on several demographic characteristics such as age, diagnosis and functi oning level, history of reinforcement for problem behavior, and so forth. Therefore, it is somewhat possible that these characteristics contributed (at least in part) to the idiosyncratic results that were obtained in both Study 1 and Study 2. Future research may examine this possibility by evaluating the effects of negative reinforcement

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51 magnitude and quality on the escape-maintained behavior of individuals whose characteristics are more similar. Finally, our reason for examining the effect s of competing contingencies for problem behavior maintained by escape is that caregivers often do not implement EXT which leads to questions about why not, and whether there are ways to improve car egivers correct use of this procedure. Additional research in this area therefore is needed. One approach would be to conduct descriptive analyses (B ijou, Peterson, & Ault, 1968) of car egivers use of escape EXT during naturally occurring demand situations, wh ich would provide information regarding what actually happens when tasks are presented. For exam ple, is it simply a matter of inconsistent (intermittent) application? Or do suspected probl ems (i.e., physical resistance on the part of the client) actually occur? This information might prove useful in designi ng strategies that may improve the consistency with which escape EXT is implemented by caregivers across relevant environments. In summary, these studies extend previous research on treatments without EXT by evaluating the effects of quantitativ e and qualitative parameters of negative reinforcement on compliance and on problem behavior that occurs in the context of demands. Although positive reinforcement long has been recognized as a potent source of reinforcement for problem behavior, and treatment for this function generally is well und erstood, the role that negative reinforcement plays in the maintenance of bot h appropriate and probl em behavior shown by individuals with developmental di sabilities is less well developed (cf. Iwata, 1987). The utility of negative reinforcement for an appropriate compe ting response (compliance) in the absence of EXT is not evident, and the use of positive reinfo rcement for appropriate behavior is not simply a matter of competition between different reinforcers, but competition between different

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52 contingencies. Therefore, a number of paramete rs and contingency relations have yet to be explored in the treatment of problem behavior maintained by escape, and the hope is that this study will assist in guidi ng that line of research.

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53 Table 2-1. Subject characteristics Name Age Classification Definiti on of Target Problem Behaviors Emma 11 Down syndrome, MR Property destruction (throwing items a distance of 6 or more, tipping over furniture) Braxton 19 Cerebral palsy, seizure disorder, MR SIB (hand biting: inserting palm past plane of the lips while forcefully biting down) Tim 21 Angelman syndrome, seizure disorder, MR Property destruction (tearing paper or clothing by at least 1 or audibly, throwing or swiping items a distance of 6 or more) Gary 12 Autism Aggression (hitting or kicking from a distance of at least 6 or audibly, head butting) John 6 Autism Property destruction (throwing or swiping objects a distance of 6 or more, knocking over furniture) Rita 17 Angelman syndrome, MR Aggre ssion (hair pulling, hitting from a distance of at least 6 or audibly, pushing such that the therapist or wheelchair moves) Keith 43 Seizure disorder, MR Property destruction (throwing items a distance of 6 or more, ripping paper, hitting walls or furniture from a distance of at least 6 or audibly, tearing paper off of walls, knocking over furniture) Ethan 4 PDD-NOS Aggression (h itting or kicking from a distance of at least 6, biting or attempts to bite by placing mouth within 1 of therapists body part, scratching by moving fingers at least 1 along therapists skin, pushing therapist with his body) Kendra 10 Seizure disorder, retinopathy of the eye SIB (hand biting: inserting palm past plane of the lips and biting down with teeth-toskin contact)

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54 Table 3-1. Task demands included for each subject in Study 1 Name Definition of Task Demands Emma Sit at desk or table, place objects in a bin, touch body part (e.g., hair, belly, nose) Braxton Touch card, hand therapist card, touc h body part (e.g., ear, head, belly, elbow) Tim Sit in chair, fold paper or clothing, stack paper, hand therapist paper, pick up trash, put items in trash bag Gary Object identification (i.e., point to [x]), write letter G John Sit in chair, establish eye contact with the therapist (i.e., look at me), object identification (i.e., touch [x]), hand therapist object, place objects in bin Rita Touch card, hand therapist card, t ouch body part (e.g., head, nose, belly) Keith Sit in chair, draw a line, wipe su rface, hand experimenter object, put on shoe

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55 Table 3-2. Means and ranges of depende nt measures for each subject Study 1 Name Condition Problem behavior Compliance Emma BL 4.4 rpm (range, 0.36 to 9.87 rpm) 14.5% (range, 0 to 27.8%) 30/ 30 0.98 rpm (range, 0 to 2.86 rpm) 40.4% (range, 9.5 to 64.7%) Braxton BL 1.0 rpm (range, 0.24 to 1.68 rpm) 4.16% (range, 0 to 13%) 30/ 30 0.02 rpm (range, 0 to 0.23 rpm) 17.6% (range, 10.7 to 21.9%) 120/ 30 0.05 rpm (range, 0 to 0.53 rpm) 20.1% (range, 14.8 to 28.6%) Tim BL 6.86 rpm (range, 1.53 to 12.3 rpm) 15.0% (range, 0 to 45.8%) 30/ 30 2.87 rpm (range, 0 to 8.46 rpm) 56.8% (range, 25.0 to 92.3%) 120/ 30 3.03 rpm (range, 1.08 to 7.14 rpm) 59.4% (range, 33.3 to 83.3%) 120/ 5 2.57 rpm (range, 0.65 to 5.52 rpm) 57.2% (range, 33.3 to 83.3%) Sr+/ S r 0.16 rpm (range, 0 to 0.69 rpm) 89.4% (range, 78.3 to 98.1%) Gary BL 17.8 rpm (range, 3.14 to 28.4 rpm) 14.4% (range, 5.26 to 36%) 30/ 30 17.7 rpm (range, 13 to 25.4 rpm) 6.93% (range, 5.55 to 11.8%) 120/ 30 27.1 rpm (range, 20 to 31.1 rpm) 6.27 % (range, 5.88 to 6.67%) 120/ 5 32.4 rpm (range, 30.3 to 33.4 rpm) 1.95% (range, 1.79 to 2.22%) Sr+/ S r 25.2 rpm (range, 18 to 37.5 rpm) 5.26% (range, 5.26 to 5.26%) Sr+/ EXT 0.08 rpm (range, 0 to 0.1 rpm) 98.9% (range, 96.3 to 100%) John BL 2.22 rpm (range, 1.66 to 3.27 rpm) 5.01% (range, 0 to 9.52%) 30/ 30 1.77 rpm (range, 0.9 to 2.39 rpm) 16.4% (range, 0 to 62.5%) 120/ 30 1.82 rpm (range, 1.54 to 2.23 rpm) 8.51% (range, 5.56 to 13.3%) 120/ 5 3.4 rpm (range, 2.54 to 3.92 rpm) 8.91 (range, 6.9 to 11.5%) Sr+/ S r 2.49 rpm (range, 1.08 to 4.2 rpm) 37.2% (range, 17.7 to 52.2%) Sr+/ EXT 0.37 rpm (range, 0 to 1.2 rpm) 34.5% (range, 15.0 to 58.3%) Rita BL 7.18 rpm (range, 1.85 to 12.3 rpm) 5.17% (range, 0 to 16.7%) 30/ 30 7.86 rpm (range, 2.56 to 11.1 rpm) 11.4% (range, 0 to 31.3%) 120/ 30 6.96 rpm (range, 1.71 to 19.1 rpm) 7.03% (range, 0 to 18.2%) 120/ 5 3.29 rpm (range, 0.86 to 8.37 rpm) 20.7% (range, 2.44 to 50.0%) Sr+/ S r 3.51 rpm (range, 0.51 to 4.96 rpm) 16.6% (range, 7.4 to 30.0%) Sr+/ EXT 0.56 rpm (range, 0 to 1.3 rpm) 13.3% (range, 10.6 to 14.9%) Keith BL 9.79 rpm (range, 5.35 to 14.1 rpm) 8.73% (range, 0 to 14.3%) 30/ 30 12.6 rpm (range, 8.29 to 15.7 rpm) 12.0% (range, 0 to 27.8%) 120/ 30 14.5 rpm (range, 8.3 to 20.5 rpm) 26.3% (range, 15.4 to 44.4%) 120/ 5 9.75 rpm (range, 3.14 to 25.5 rpm) 29.7% (range, 15.8 to 45.5%) Sr+/ S r 7.0 rpm (range, 5.7 to 8.6 rpm) 32.3% (range, 27.0 to 42.0%) Sr+/ EXT 0.87 rpm (range, 0 to 2.8 rpm) 56.2% (range, 37.1 to 76.7%) Summary data for the first BL phase and la st effective treatment phase are reported.

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56 Table 4-1. Task demands included for each subject in Study 2 Name Definition of Task Demands Ethan Sit down, stand up, touch body part (e.g., hea d, nose, ear), count to (x), object identification (e.g., show me [x], point to the [x] on the left/right, etc.) Keith Stack chairs, string bead, put puzzle piece in puzzle, zip bag, put on jacket, put on shoe Kendra Sit down, stand up, clap hands, put on shirt, put on shoe Table 4-2. Means and ranges of depende nt measures for each subject Study 2 Name Condition Problem behavior Compliance Ethan BL 15.2 rpm (range, 11.7 to 20.7 rpm) 12.8% (range, 0 to 34.7%) 30/ 30 12.6 rpm (range, (9.15 to 16.5 rpm) 16.2% (range, 5.5 to 29.4%) S r -/ LQ S r 0.15 rpm (range, 0 to 1.65 rpm) 90.7% (range, 62.5 to 100%) Keith BL 10.6 rpm (range, 3.0 to 18.5 rpm) 14.6% (range, 0 to 38.9%) 30/ 30 9.97 rpm (range, 2.11 to 19.3 rpm) 23.6% (range, 0 to 60.0%) S r -/ LQ S r 0.93 rpm (range, 0 to 18.1 rpm) 67.7% (range, 4.3 to 80.0%) Kendra BL 1.94 rpm (range, 0.5 to 4.62 rpm) 1.92% (range, 0 to 11.0%) 30/ 30 1.58 rpm (range, 0.38 to 4.0 rpm) 11.4% (range, 0 to 40.0%) S r -/ LQ S r 5.69 rpm (range, 3.11 to 7.55 rpm) 11.8% (range, 10.3 to 12.5%) Sr+/ LQ S r 0.01 rpm (range, 0 to 0.1 rpm) 97.8% (range, 93.9 to 100%) Summary data for the first BL phase and la st effective treatment phase are reported.

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57 LIST OF REFERENCES Bijou, S. W., Peterson, R. F., & Ault, M. H. (1968). A method to integrate descriptive and experimental field studies at the le vel of data and empirical concepts. Journal of Applied Behavior Analysis, 1, 175-191. Carr, E. G. (1977). The motivation of self-injur ious behavior: A review of some hypotheses. Psychological Bulletin, 84 800-816. Carr, E. G., & Durand, M. V. (1985). Reduci ng behavior problems through functional communication training. Journal of Applied Behavior Analysis, 18 111-126. Carr, J. E., Bailey, J. S., Ecott, C. L., Lucker, K. D., & Weil, T. M. (1998). On the effects of noncontingent delivery of differi ng magnitudes of reinforcement. Journal of Applied Behavior Analysis, 31, 313-321. Carr, J. E., Coriaty, S., Wilder, D. A., Gaunt, B. T., Dozier, C. L., Britton, L. N., Avina, C., & Reed, C. L. (2000). A review of "nonconti ngent" reinforcement as treatment for the aberrant behavior of individuals with developmental disabilities. Research in Developmental Disabilities, 21 377-391. Cataldo, M. F. (1991). The effects of punishment and other behavior redu cing procedures on the destructive behavior of persons with developmental disabiliti es. In U.S. Department of Health and Human Services, Treatment of destructive behaviors in persons with developmental disabilities (pp. 231-341) (NIH Publica tion No. 91-2410). Bethesda, MD: National Institutes of Health. Catania, A. C. (1963). Concurrent performan ces: A baseline for the study of reinforcement magnitude. Journal of the Experimental Analysis of Behavior, 6 299-300. Cipani, E., & Spooner, F. (1997). Treating problem behaviors maintained by negative reinforcement. Research in Developmental Disabilities, 18, 329-342 Conners, J., Iwata, B. A., Kahng, S. W., Hanley, G. P., Worsdell, A. S., & Thompson, R. H. (2000). Differential responding in the presen ce and absence of discriminative stimuli during multielement functional analyses. Journal of Applied Behavior Analysis, 33 299308. DeLeon, I. G. & Iwata, B. A. (1996). Evaluation of a multiple-stimulus presentation format for assessing reinforcer preferences. Journal of Applied Behavior Analysis, 29 519-533. DeLeon, I. G., Neidert, P. L., Anders, B. M., & Rodriguez-Catter, V. (2001). Choices between positive and negative reinforcement during treatment for escape-maintained behavior. Journal of Applied Behavior Analysis, 34 521-525.

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58 Derby, K. M., Wacker, D. P., Sasso, G., Steege, M., Northup, J., Cigrand, K., & Asmus, J. (1992). Brief functional assessment techniques to evaluate aberrant behavior in an outpatient setting: A summary of 79 cases. Journal of Applied Behavior Analysis, 25, 713-721. Egel, A. L. (1981). Reinforcer variation: Impli cations for motivating developmentally disabled children. Journal of Applied Behavior Analysis, 14 345-350. Ferster, C. B., & Skinner, B. F. (1957). Schedules of reinforcement. New York: AppletonCentury-Crofts. Fisher, W. W., & Mazur, J. E. (1997). Ba sic and applied research on choice responding. Journal of Applied Behavior Analysis, 30, 387-410. Fisher, W., Piazza, C. C., Bowman, L. G., Hagopian, L. P., Owens, J. C., & Slevin, I. (1992). A comparison of two approaches for identifying reinforcers for persons with severe and profound disabilities. Journal of Applied Behavior Analysis, 25 491-498. Goh, H., & Iwata, B. A. (1994). Behavioral persis tence and variability dur ing extinction of selfinjury maintained by escape. Journal of Applied Behavior Analysis, 27 173-174. Golonka, Z., Wacker, D., Berg, W., Derby, K. M ., Harding, J., & Peck, S. (2000). Effects of escape to alone versus escape to enrich ed environments on adaptive and aberrant behavior. Journal of Applied Behavior Analysis, 33 243-246. Hanley, G. P., Iwata, B. A., & McCord, B. E. (2003). Functional analysis of problem behavior: A review. Journal of Applied Behavior Analysis, 36, 147-185. Hoch, H., McComas, J. J., Thompson, A. L., & Paone, D. (2002). Concurrent reinforcement schedules: Behavior change a nd maintenance without extinction. Journal of Applied Behavior Analysis, 35 155-169. Horner, R. H. & Day, H. M. (1991). The effects of response efficiency on functionally equivalent competing behaviors. Journal of Applied Behavior Analysis, 24, 719-732. Individuals with Disabilities Education Act Amendments of 1997, 20 U.S.C. 1414(d) (Supp. III 1997). Iwata, B. A. (1987). Negative reinforcement in applied behavior analysis: An emerging technology. Journal of Applied Behavior Analysis, 20 361-378. Iwata, B. A., Dorsey, M. F., Slifer, K. J., Ba uman, K. E., & Richman, G. S. (1994). Toward a functional analysis of self-injury Journal of Applied Behavior Analysis, 27 197-209. Reprinted from Analysis and Intervention in De velopmental Disabilities, 2 3-20, 1982.

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59 Iwata, B. A., Kahng, S., Wallace, M. D., & Lindberg, J. L. (2000). The functional analysis model of behavioral assessment. In J. Austin & J. E. Carr (Eds.), Handbook of applied behavior analysis (pp. 61-89). Reno, NV: Context Press. Iwata, B. A., Pace, G. M., Cowdery, G. E., & Mi ltenberger, R. G. (1994). What makes extinction work: An analysis of procedural form and function. Journal of Applied Behavior Analysis, 27, 131-144. Iwata, B. A., Pace, G. M., Dorsey, M. F., Zarcone J. R., Vollmer, T. R., Smith, R. G., Rodgers, T. A., Lerman, D. C., Shore, B. A., Mazaleski, J. L., Goh, H., Cowdery, G. E., Kalsher, M. J., McCosh, K. C., & Willis, K. D. (1994). The functions of self -injurious behavior: An experimental-epidemiological analysis. Journal of Applied Behavior Analysis, 27 215-240. Iwata, B. A., Pace, G. M., Kalsher, M. J., Cowdery, G. E., & Cataldo, M. F. (1990). Experimental analysis and extinction of self-injurious escape behavior. Journal of Applied Behavior Analysis, 23 11-27. Iwata, B. A., Vollmer, T. R., Zarcone, J. R., & Rodgers, T. A. (1993). Treatment classification and selection based on behavioral function. In R. Van Houten & S. Axelrod (Eds.), Behavior analysis and treatment (pp. 102-125). New York: Plenum. Kodak, T., Lerman, D. C., Volkert, V. M., & Trosclair, N. (2007). Further examination of factors that influence preference for positive versus negative reinforcement. Journal of Applied Behavior Analysis, 40, 25-44. Kodak, T., Miltenberger, R. G., & Romaniuk, C. (2003). The effects of differential negative reinforcement of other behavior a nd noncontingent escape on compliance. Journal of Applied Behavior Analysis, 36 379-382. Lalli, J. S., & Casey, S. D. (1996). Treatment of multiply controlled problem behavior. Journal of Applied Behavior Analysis, 29, 391-395. Lalli, J. S., Vollmer, T. R., Progar, P. R., Wrig ht, C., Borrero, J., Daniel, D., Hoffner Barthold, C., Tocco, K., & May, W. (1999). Competition between positive and negative reinforcement in the treatment of escape behavior. Journal of Applied Behavior Analysis, 32, 285-296. Lerman, D. C., & Iwata, B. A. (1996). A met hodology for distinguishing between extinction and punishment effects associated with response blocking. Journal of Applied Behavior Analysis, 29, 231-233. Lerman, D. C., & Iwata, B. A. (1996). Developing a technology for the us e of operant extinction in clinical settings: An examinati on of basic and applied research. Journal of Applied Behavior Analysis, 29 345-382.

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60 Lerman, D. C., Iwata, B. A., & Wallace, M. D. ( 1999). Side effects of extinction: Prevalence of bursting and aggression dur ing treatment of self-injurious behavior. Journal of Applied Behavior Analysis, 32, 1-8. Lerman, D. C., Kelley, M. E., Van Camp, C. M., & Roane, H. S. (1999). Effects of reinforcement magnitude on spontaneous recovery. Journal of Applied Behavior Analysis, 32, 197-200. Lerman, D. C., Kelley, M. E., Vorndran, C. M ., Kuhn, S. A. C., & LaRue, R. H. Jr. (2002). Reinforcement magnitude and respondi ng during treatment with differential reinforcement. Journal of Applied Behavior Analysis, 35, 29-48. Mace, F. C., & Belfiore, P. (1990). Behavioral momentum in the treatment of escape-motivated stereotypy. Journal of Applied Behavior Analysis, 23 507-514. Mace, F. C., Neef, N. A., Shade, D., & Mauro, B. C. (1996). Effects of problem difficulty and reinforcer quality on time allocated to concurrent arithmetic problems. Journal of Applied Behavior Analysis, 29 11-24. Marcus, B. A., & Vollmer, T. R. (1995). Effects of differential negative reinforcement on disruption and compliance. Journal of Applied Behavior Analysis, 28 229-230. Mazaleski, J. L., Iwata, B. A., Vollmer, T. R., Za rcone, J. R., & Smith, R. G. (1993). Analysis of the reinforcement and extinction components in DRO contingencies with self-injury. Journal of Applied Behavior Analysis, 26 143-156. McComas, J. J., Goddard, C., & Hoch, H. (2002). The effects of pref erred activities during academic work breaks on task engagement and negatively reinforced destructive behavior. Education and Treatment of Children, 25 103-112. Neef, N. A., Mace, F. C., & Shade, D. (1993). Impulsivity in students with serious emotional disturbance: The interactive effects of reinforcer rate, delay, and quality. Journal of Applied Behavior Analysis, 26 37-52. Neef, N. A., Mace, F. C., Shea, M. C., & Shad e, D. (1992). Effects of reinforcer rate and reinforcer quality on time allocation: Extens ions of matching theory to educational settings. Journal of Applied Behavior Analysis, 25, 691-699). Neef, N. A., Marckel, J., Ferreri, S. J., Bicard, D. F., Endo, S., Aman, M. G ., Miller, K. m., Jung, S., Nist, L., & Armstrong, N. (2005). Behavioral assessment of impulsivity: A comparison of children with and without attention deficit hyp eractivity disorder. Journal of Applied Behavior Analysis, 38, 23-37. Neef, N. A., Shade, D., & Miller, M. S. 91994). Assessing influential dime nsions of reinforcers on choice in students with seri ous emotional disturbance. Journal of Applied Behavior Analysis, 27, 575-583.

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61 Pace, G. M., Ivancic, M. T., & Jefferson, G. (1994) Stimulus fading as treatment of obscenity in a brain-injured adult. Journal of Applied Behavior Analysis, 27 301-305. Pace, G. M., Iwata, B. A., Cowdery, G. E., Andree, P. J., & McIntyre, T. (1993). Stimulus (instructional) fading duri ng extinction of self-inj urious escape behavior. Journal of Applied Behavior Analysis, 26 205-212. Peck, S. M., Wacker, D. P., Berg, W. K., Cooper, L. J., Brown, K. A., Richman, D., McComas, J. J., Frischmeyer, P., & Millard, T. (1996) Choice-making treatment of young childrens severe behavior problems. Journal of Applied Behavior Analysis, 29, 263-290. Pelios, L., Morren, J., Tesch, D., & Axelrod, S. (1999). The impact of functional analysis methodology on treatment choice for self-i njurious and aggressive behavior. Journal of Applied Behavior Analysis, 32, 185-195. Piazza, C. C., Fisher, W. W., Hanley, G. P., Remic k, M. L., Contrucci, S. A., & Aitken, T. L. (1997). The use of positive and negative re inforcement in the treatment of escapemaintained destructive behavior. Journal of Applied Behavior Analysis, 30 279-298. Powell, R. W., & Peck, S. (1969). Persistent sh ock-elicited responding engendered by a negative reinforcement procedure. Journal of the Experimental Analysis of Behavior, 12, 10491062. Rachlin, H. (1974). Self-control. Behaviorism, 2, 94-107. Reed, P. (1991). Multiple determinants of the eff ects of reinforcement magnitude on free-operant response rates. Journal of the Experimental Analysis of Behavior, 55 109-123. Reed, P., & Wright, J. E. (1988). Effects of ma gnitude of food reinforc ement on free-operant response rates. Journal of the Experimental Analysis of Behavior, 49 75-85. Romaniuk, C., Miltenberger, R., Conyers, C., Jenne r, N., Jurgens, M., & Ringenberg, C. (2002). The influence of activity choice on problem behaviors maintained by escape versus attention. Journal of Applied Behavior Analysis, 35 349-362. Roscoe, E. M., Iwata, B. A., & Rand, M. S. (2003). Effects of reinforcer consumption and magnitude on response rates duri ng noncontingent reinforcement. Journal of Applied Behavior Analysis, 36 525-539. Sidman, M., Herrnstein, R. J., & Conrad, D. G. (1957). Maintenance of avoidance behavior by unavoidable shocks. Journal of Comparative and Physiological Psychology, 50, 553-557. Smith, R. G., Russo, L., & Le, D. D. (1999). Di stinguishing between extinction and punishment effects of response blocking: A replication. Journal of Applied Behavior Analysis, 32, 367-370.

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62 Smolev, S. R. (1971). Use of opera nt techniques for the modificati on of self-injurious behavior. American Journal of Mental Deficiency, 76, 295-305. Solnick, J. V., Kannenberg, C. H., Eckerman, D. A., & Waller, M. B. (1980). An experimental analysis of impulsivity and impulse control in humans. Learning and Motivation, 11, 6177. Trosclair-Lasserre, N. M., Lerman, D. C., Ca ll, N. A., Addison, L. R., & Kodak, T. (2008). Reinforcement magnitude: An evaluation of preference and reinforcer efficacy. Journal of Applied Behavior Analysis, 41, 203-220. Vollmer, T. R. (1999). Noncontingent reinforcement: Some additional comments. Journal of Applied Behavior Analysis, 32, 239-240. Vollmer, T. R., & Iwata, B. A. (1992). Different ial reinforcement as treatment for behavior disorders: Procedural an d functional variations. Research in Developmental Disabilities, 13, 393-417. Vollmer, T. R., Marcus, B. A., & Ringdahl, J. E. (1995). Nonconti ngent escape as treatment for self-injurious behavior mainta ined by negative reinforcement. Journal of Applied Behavior Analysis, 28 15-26. Vollmer, T. R., Roane, H. S., Ringdahl, J. E., & Marcus, B. A. (1999). Evaluating treatment challenges with differential reinforcement of alternative behavior. Journal of Applied Behavior Analysis, 32 9-23. Weeks, M., & Gaylord-Ross, R. (1981). Task di fficulty and aberrant behavior in severely handicapped students. Journal of Applied Behavior Analysis, 14 449-463. Wilder, D. A., Normand, M., & Atwell, J. (2005) Noncontingent reinforcement as treatment for food refusal and associated self-injury. Journal of Applied Behavior Analysis, 38, 549553. Zarcone, J. R., Iwata, B. A., Hughes, C. E ., & Vollmer, T. R. (1993). Momentum versus extinction effects in the treatment of self-injurious escape behavior. Journal of Applied Behavior Analysis, 26 135-136. Zarcone, J. R., Iwata, B. A., Mazaleski, J. L., & Smith, R. G. (1994). Momentum and extinction effects on self-injurious be havior and noncompliance. Journal of Applied Behavior Analysis, 27 649-658. Zarcone, J. R., Iwata, B. A., Smith, R. G., Mazaleski, J. L., & Lerman, D. C. (1994). Reemergence and extinction of self-injur ious escape behavi or during stimulus (instructional) fading. Journal of Applie d Behavior Analysis 27 302-316.

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63 BIOGRAPHICAL SKETCH Jennifer Hammond completed her bachelors de gree in psychology at the University of California, S anta Cruz in 1999 while gaining clinical experience w ith individuals with developmental disabilities. She subsequently ob tained her masters degree in psychology at California State University, Stanislaus in 2001, where she c ontinued to work and conduct research with children and adolescents diagnosed with a range of disabilities, including autism. Jennifer enrolled in the Ph.D. program in behavior analysis at the University of Florida in 2004, where she focused her studies on disorders of learning and behavior in developmental disabilities. She conducted clinical research in outpatient clinics, schools, and residential settings, and served as Clinical Director of a program for individua ls with Prader-Willi Syndrome, while teaching courses in applied be havior analysis. Following graduation, Jennifer will begin a post-doctoral fellowshi p in psychiatry at Stanford University School of Medicine, where she will conduct interdisciplinary res earch on the neurological and environmental contributions to various genetic di sorders and behavioral phenotypes.