Extended Data Fig. 21: MOp-ul regional & cell type networks.

MOp-ul shares extensive bidirectional connections with other cortical areas, including bilateral projections to MOs, SSp, SSs, TEa, and to the contralateral MOp. Although MOp-ul is considered as a single gray matter region node (macroscale), the more than 15 IT projection neuron types revealed here suggest a very complex network at the mesoscale. Two network schematics show three general categories of IT cell type-specific connections: (1) single target types (black arrows, one target, e.g., MOp-ul to MOs); (2) broadcasting types, in which one cell type innervates many cortical targets of MOp-ul (red); (3) multiple combinatorial targets types, in which one cell type projects variably to several targets. Note that in this model and in the case of multiple models coexisting, each cortical target receives inputs from multiple types of MOp-ul IT neurons.