Robust non-monotonic relationship between output correlation and strength of inhibitory feedback

A non-monotonic relationship between the output correlation and the strength of inhibitory feedback in a two-layer network of excitatory and inhibitory neurons is found in the present paper, which indicates that the inhibitory connection does not always enhance the correlative activities of neurons as revealed by previous studies. By numerical simulations, we also find that the non-monotonic relationship is preserved with heterogeneous firing threshold and inhibitory feedback gain. Therefore, the non-monotonic relationship is robust which tolerates a moderate level of heterogeneity in the network.