Fig. 2.
Presynaptic population model. A: each of ne = 150 presynaptic spike trains drives M = 5 synaptic contacts to produce the first neuron's total excitatory synaptic conductance, gE,1(t). The sum of these presynaptic spike trains is denoted E1(t) and similarly for E2(t), I1(t), and I2(t). Every pair of presynaptic spike trains is correlated with coefficient, ρin(t). Correlation between the excitatory population spike trains is denoted ρEE(t) and similarly for ρII (t) and ρEI(t). B: population conductances, gE,2(t), gI,1(t), and gI,2(t) are constructed analogously to gE,1(t) in A and their pairwise correlations are denoted ρgEgE(t), ρgIgI(t), and ρgEgI (t). Population conductances drive two postsynaptic neurons to produce two output spike trains, s1(t) and s2(t), with correlation given by ρout(t). We are interested in how ρin(t) is transferred to ρout(t).