Developmental and Evolutionary Origins of Cortical Projection Neuron Identity and Connectivity

Precise motor movements, higher-order cognitive functions, and sensory and emotional processing depend on proper laminar and areal organization of the cerebral cortex. The processes behind the laminar and areal layout of the cortex are complex and largely depend on the generation of diverse subtypes of excitatory projection neurons and the acquisition of their precise connectivity. Although most developmental mechanisms governing the identity and connectivity of cortical projection neurons are conserved among mammals, certain compelling interspecies differences facilitate unique patterns of molecular features and connectivity that underlie different cognitive and behavioral abilities amongst species. Disruptions during development, whether genetic or environmental, can affect neuronal specification and differentiation, leading to an increased risk of neurodevelopmental and neuropsychiatric disorders. Therefore, a better understanding of the multifactorial processes governing cortical neuron identity and connectivity is crucial for understanding the developmental and evolutionary origins of higher-order cognition and complex behavior and may even aid in understanding neuropsychiatric disorders.* Correspopnding author