Summary
One of the most enduring themes in human neuroscience is the association of higher brain functions with gray matter. In particular, the cerebral cortex—the gray matter of the brain’s surface—has been the primary focus of decades of work aiming to understand the neurobiological basis of cognition and emotion. Yet, the cerebral cortex is only a few millimeters thick, so the relative neglect of the rest of the brain below the cortex has prompted the term “corticocentric myopia” (1). Other regions relevant to behavior include the deep gray matter of the basal ganglia and thalamus, the brainstem and cerebellum, and the white matter that interconnects all of these structures. On page 1304 of this issue, Zhao et al. (2) present compelling evidence for the importance of white matter by demonstrating genetic influences on structural connectivity that invoke a host of provocative clinical implications.