Figure 5.

Divergent connection selectivity from L2/3 to L5 pyramidal subtypes. A, Dual whole-cell recordings from L5 pyramidal cells. Left, Identification of firing subtypes (cell-1, SA-d; cell-2, SA). Right, EPSCs in cell-2 induced by cell-1 spikes. B, Divergence connections to two L5 pyramidal subtypes tested by L2/3 cell stimulation by glutamate puff. C, EPSC induction in two L5 cells. Left, EPSCs observed only in one cell; right, common inputs induced by L2/3 cell stimulation. D, Top box, Observed connection probabilities from L2/3 to L5 pyramidal subtypes. Bottom box, Calculation of common input probabilities assuming nonselective innervations. E, Probabilities that two L5 pyramidal cells share common inputs from a L2/3 cell in the case of unconnected L5 pairs, relative to those assuming nonselective cases. The common input probabilities were compared between subtype combinations of L5 pairs. Data are means ± SD; **p < 0.01.