Fig. 6.

Approach to subdivide a neuronal family into functionally distinct subclasses based on transcriptomics, morphophysiological analysis, and optogenetic assessment of impact. Top rows, Summary of overall workflow (gray arrows) and operational steps. Bottom rows, Summary of four subpopulations and some defining characteristics, including morphological ranking with regard to soma proximity to pyramidal layer and axonal extension away from pyramidal layer (Fig. 1); membership in electrophysiological clusters (Fig. 2); optogenetically assessed postsynaptic targeting (Fig. 3); functional impact (Fig. 4); and synaptic recruitment in the hippocampal circuit (Fig. 5).