Impact of Network Structure and Cellular Response on Spike Time Correlations
Figure 7
Correlations in random, fixed in-degree networks.
(A) A comparison of numerically obtained excitatory-inhibitory cross-correlations to the approximation given by Eq. (26). (B) Mean and standard deviation for the distribution of correlation functions for excitatory-inhibitory pairs of cells. (Solid line – mean cross-correlation, shaded area – one standard deviation from the mean, calculated using bootstrapping in a single network realization). (C) Mean and standard deviation for the distribution of cross-correlation functions conditioned on cell type and first order connectivity for a reciprocally coupled excitatory-inhibitory pair of cells. (Solid line – mean cross-correlation function, shaded area – one standard deviation from the mean found by bootstrapping). (D) Average reduction in error between cross-correlation functions and their respective first-order conditioned averages, relative to the error between the cross-correlations and their cell-type averages. Blue circles give results for a precisely tuned network, and red squares for a network with stronger, faster inhibition. Error bars indicate two standard errors above and below the mean.
for panels A-C are as in the precisely tuned network of Figure 6, and the two networks of panel D are as in the networks of the same figure.