Simulation and electrophysiological recordings of GJ-mediated responses in model and real FS pairs. A1 & B1) Repetitive spikes were evoked in a model cell (A1) and a real FS interneuron (B1). Black and gray traces were evoked by currents of 100 & 300 pA, respectively. A2& B2) F-I (frequency-current) plot of the model FS neuron (A2) and a real FS cell (B2). C) Presynaptic (black) and postsynaptic responses in a GJ coupled FS pair recorded in slice in the absence (C1) and presence of GJ inhibitor carbenoxalone (C2). C3: Spike synchronization is strong in C1 and weak in C2. D) Representative traces (D1) and spike probability plot (D2) showing that the spike transmission depends on the membrane potential of the postsynaptic cell.