Intrinsic neuronal diversity as a substrate for cortical area specialization in primate vision

Abstract

Abstract In primates, primary visual cortex (V1) circuits support early visual processing, whereas in the lateral prefrontal cortex (LPFC), they support higher-order computations. Here, we characterized the intrinsic electrophysiological (e)-properties and morphology of excitatory (EXC), fast-spiking inhibitory (FSI), and non-fast-spiking inhibitory (NFSI) neurons in layers I-III of V1 and LPFC, of a small primate, the common marmoset. EXC and FSI neurons exhibited broader action potentials in LPFC than in V1. Compared to V1, LPFC EXC neurons exhibited reduced excitability, whereas FSI neurons showed increased excitability. NFSI neurons showed fewer area-specific differences. Notably, EXC and FSI neurons displayed increased bursting in LPFC compared to V1. Morphologically, LPFC-EXC neurons exhibited longer dendritic arbors, whereas LPFC-FSI neurons showed greater axonal complexity relative to V1. Our findings demonstrate area-specific functional and anatomical diversification of major neuronal types in layers I-III of the primate neocortex and provide an open-access resource for studies of neocortical cell types.