Feedback-dependence and robustness of gamma oscillations in networks with excitatory and inhibitory neurons

Synchronous rhythmic firing activity is fundamental tool for encoding and exchanging information in the brain. Based on inhibitory feedback neural network model, the network oscillations and the effect of the heterogeneity in the network on the oscillatory firing activity are studied. By using numerical simulations, global network oscillations in the gamma frequency band are obtained. The power of gamma oscillations is proportional to the inhibitory feedback gain. When the network model is heterogeneous, the gamma oscillations are robust with a moderate amount of heterogeneity. Stronger inhibitory feedback is beneficial to improve the robustness of the network oscillations against the heterogeneity. The network model in this paper can achieve robust gamma oscillations against a degree of heterogeneity, which is comparable to that observed in real neural systems. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of [CEIS 2011]