BMC Meuroscience
Poster presentation
Synchrony with shunting inhibition
Sachin S Talathi*, DongUk Hwang, Abraham Miliotis, Paul R Carney and
William L Ditto
Address: Department of Biomedical Engineering, University of Florida, Gainesville, Florida, 32611, USA
Email: Sachin S Talathi* sachin.talathi@bme.ufl.edu
* Corresponding author
from Eighteenth Annual Computational Neuroscience Meeting: CNS*2009
Berlin, Germany. 1823 July 2009
Published: 13 July 2009
BMCNeuroscience 2009, I 0(Suppl 1):P233 doi:10.1186/1471220210SIP233
This abstract is available from: http://www.biomedcentral.com/14712202/10/SI/P233
2009 Talathi et al; licensee BioMed Central Ltd.
Spike time response curves (STRC's) are used to study the
influence of synaptic stimuli on the firing times of a neu
ron oscillator without the assumption of weak coupling.
They allow us to approximate the dynamics of synchro
nous state in networks of neurons through a discrete map.
Linearization about the fixed point of the discrete map
can then be used to predict the stability of patterns of syn
chrony in the network. General theory for taking into
account the contribution from higher order STRC terms,
in the approximation of the discrete map for coupled neu
ronal oscillators in synchrony is still lacking. Here we
present a general framework to account for higher order
STRC corrections in the approximation of discrete map to
determine the domain of 1:1 phase locking state in the
network of two interacting neurons. We begin by demon
strating that the effects of synaptic stimuli through a
shunting synapse to a neuron firing in the gamma fre
quency band (2080 Hz) last for three consecutive firing
cycles (See Figure 1). We then show that the discrete map
derived by taking into account the higher order STRC con
tributions is successfully able predict the domain of syn
chronous 1:1 phase locked state in a network of two
heterogeneous interneurons coupled through a shunting
synapse (See Figure 2).
Acknowledgements
The work was funded through the grant from the Office of Naval Nesearch
(N000140211019).
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Figure I
(a) Schematic diagram demonstrating the effect of perturba
tion received by a spiking neuron at time t. The cycle con
taining the perturbation defines the first order STRC and the
subsequent cycles define the higher order STRC terms. (b)
The STRC's computed for neuron receiving perturbation
through a GABAA mediated synapse at hyperpolarizing
reversal potential of ER = 80 mV. (c) The STRC's computed
for neuron receiving perturbation through a GABAA medi
ated synapse at shunting reversal potential of ER = 55 mV.
The resting membrane potential of neuron is 65 mV. The
synaptic parameters are tR = 0.1 ms, tD = 8 ms, g, = 0.15 mS/
cm2. The intrinsic period of firing for the neuron was To = 31
ms.
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BioMed Central
http://www.biomedcentral.com/14712202/10/S1/P233
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Figure 2
(a) Schematic diagram of the network considered: Two neu
rons with heterogeneity in their firing rates coupled through
a shunting inhibitory synapse. (b) Schematic diagram repre
senting spike timing for neurons A and B when they are
phase locked in 1:1 synchrony. In (c) and (d) we show
domain of 1:1 synchrony (phase locked state) estimated
through STRC's from the discrete map derived by taking into
account higher order STRC contributions for shunting syn
apse.
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BMC Neuroscience 2009, 10(Suppl 1):P233
