Vestibulo-ocular Reflex Function in Autism Spectrum Disorders

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Material Information

Title:
Vestibulo-ocular Reflex Function in Autism Spectrum Disorders
Physical Description:
1 online resource (175 p.)
Language:
english
Creator:
Carson, Tana B
Publisher:
University of Florida
Place of Publication:
Gainesville, Fla.
Publication Date:

Thesis/Dissertation Information

Degree:
Doctorate ( Ph.D.)
Degree Grantor:
University of Florida
Degree Disciplines:
Psychology
Committee Chair:
LEWIS,MARK HENRY
Committee Co-Chair:
DEVINE,DARRAGH P
Committee Members:
VOLLMER,TIMOTHY RAYMOND
HASS,CHRISTOPHER J
REYNOLDS,STACEY E
SCHUBERT,MICHAEL C

Subjects

Subjects / Keywords:
autism -- cerebellum -- motor -- oculomotor -- reflex -- sensory -- vestibular -- vestibulo-ocular
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:
Autism spectrum disorders (ASD) are characterized by social and communication skill deficits and excessive restricted/repetitive behaviors (APA, 2000; DSM-IV TR). Additional features commonly noted in ASD are deficits in sensory processing and motor control. Some motor control differences reported in ASD include decreased postural stability, decreased muscle tone, altered vestibulo-ocular reflexes (VORs) and delayed motor milestones (Fournier et al., 2010; Ben-Sasson et al., 2009; Bhat et al., 2011;Ornitz et al., 1985). These deficits may share a common dependence upon processing of vestibular sensory input. Therefore a better understanding of the extent to which vestibular sensory processing and related motor control is compromised in ASD would be beneficial for studying the underlying neurobiology of ASD. The VOR is useful for studying vestibular related sensory motor processing in this population as it involves a relatively simple reflex system, am enable to study in very young children. The rotational vestibulo-ocular reflex (rVOR)functions to maintain stable vision by generating oculomotor responses to angular rotation head movements. Our understanding of these VOR differences in ASD is currently hindered by a paucity of studies investigating this reflex. In the current studies, children ages 6 – 12 diagnosed with autism spectrum disorders observed three main differences in rVOR metrics including: (1)increased time constant of decay of post-rotary nystagmus during velocity step tests in the dark and with fixation suppression (Chapter 2); (2) increased per-rotary nystagmus gain during velocity step tests in the dark and increased gain during sinusoidal harmonic acceleration (SHA) tests in the dark as well as fixation suppression (Chapter 2 and 3 respectively); and (3) increased phase lead during SHA tests at 0.5Hz frequency cycle (Chapter 3). Several functional measures were found to correlate with rVOR time constant differences in ASD such as: adaptive skills and balance deficits(Chapter 4). Additional aberrations in the quality of rVOR such as increased slow phase irregularities are described and methods for further analysis of these differences are discussed(Chapter 5). The current findings suggest vestibular processing deficits in the rVOR that are consistent with reports of cerebellar deficits in the ASD population and warrant further study.
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 Tana B Carson.
Thesis:
Thesis (Ph.D.)--University of Florida, 2013.
Local:
Adviser: LEWIS,MARK HENRY.
Local:
Co-adviser: DEVINE,DARRAGH P.
Electronic Access:
RESTRICTED TO UF STUDENTS, STAFF, FACULTY, AND ON-CAMPUS USE UNTIL 2015-12-31

Record Information

Source Institution:
UFRGP
Rights Management:
Applicable rights reserved.
Classification:
lcc - LD1780 2013
System ID:
UFE0045911:00001