Figure 5.
Connectivity between cell pairs of L4 interneurons and excitatory L4 spiny neurons. (A) Connectivity ratio for L4 FS interneuron–L4 spiny neuron pairs; inhibitory connectivity was found to be 67% (29 of 43 postsynaptic spiny neurons tested). Traces show average IPSPs (red, upper row) and EPSPs (blue, lower row) of unidirectional inhibitory connections (left) and reciprocal connections (right), respectively, between L4 BIns and spiny neurons (BIn, blue; SN, red). (B) AP-to-PSP latencies for reciprocal BIn–SN pairs in layer 4. The latency for the excitatory postsynaptic response was significantly longer than the inhibitory response (1.09 ± 0.31 vs. 0.55 ± 0.11 ms, P < 0.001).