Abstract

The human brain undergoes a uniquely prolonged period of cortical development. During childhood and adolescence, cortical development progresses from primary and unimodal cortices with sensory and motor functions to transmodal association cortices subserving executive, socioemotional, and mentalizing functions. The spatiotemporal patterning of cortical maturation thus proceeds in a hierarchical manner, conforming to an evolutionarily rooted, sensorimotor-to-association axis of cortical organization. This developmental program serves to enhance feature variation between lower-order and higher-order regions, endowing the brain’s association cortices with unique properties. However, protracted plasticity within late-maturing association cortices, which represents a defining feature of the human developmental program, also confers risk for mood-related psychopathology. In this talk, I will present a spatial and temporal model of human neurodevelopment that captures the protracted and heterochronous nature of cortical maturation, and that provides insight into how our species’ maturational course enhances both our cognitive repertoire and our vulnerability to affective illness. I will begin by describing hierarchical cortical topography and the sensorimotor-association axis. A review of neuroimaging evidence of hierarchical neurodevelopment will follow, with an emphasis on work that has characterized the temporal unfolding of critical period plasticity mechanisms. I will conclude by discussing how development can inform our understanding of youth mood psychopathology and windows for intervention.