Effect of the Correlation in Synaptic Background Inputs on the Regularity of Neocortical Neuron Firing Activity

Abstract

Listen

Translate article

Neocortical neurons are subject to synaptic background activity. During activated states of the brain, it becomes very intense and affects the input-output characteristics of the neuron. In this study, the effect of the correlation in synaptic background inputs on the regularity of the cortical neuron firing activity is examined. For this purpose, a recently proposed point-conductance model was used. The model considers single-compartment neuron with global excitatory and inhibitory conductances that represent the sum of a large number of synaptic inputs. Twenty-eight different values of the correlation coefficient were used in the simulations. We changed the correlation of the background activity without affecting the average conductance due to the background activity. Therefore, the neuron received the same amount of random input with different correlation at each trial. For each value of the correlation, a simulation of 200 second duration was conducted and it was repeated 100 times. In order to examine the regularity of spike sequences obtained at each trial, the coefficient of variation of interspikes intervals was computed. Obtained results suggest that the neocortical neuron can detect the change of correlation in its input and encode it by increasing the regularity of the firing for the increasing correlation.