Role of EPJP in regulating TC induced spike patterns in simulated barrel circuits. A1&B1) TC (6 stimuli@30 ms interval) induced spikes in an simulated layer 4 network containing a FS pair (red trace) and a spiny stellate pair (SS, black trace). A1: EPJP = 0 nS between FS pairs. B1: EPJP = 0.3 nS between FS pairs. Note that feed-forward IPSP in spiny stellate neurons (indicated by black arrows) follows each successive spike in FS cells. A2 &B2) Raster plot of spikes induced by TC (6 stimuli @ 30 ms intervals) inputs in networks without GJ coupling (A3) and with modest GJ coupling (0.3 nS, B3). C) Spike transmission efficacy in SS cells (number of spikes/number of TC inputs (C1) and spike synchronization (C2) in barrel circuits with (filled bar, gEPJP = 0.3 nS) and without GJ coupling (open bar), ***P < 0.01; ** p < 0.01, n = 10 trials.