Neuroimaging and neuropathological studies of depression: implications forthe cognitive-emotional features of mood disorders

Neuroimaging technology has provided unprecedented opportunities for elucid ating the anatomical correlates of major depression. The knowledge gained f rom imaging research and from the postmortem studies that have been guided by imaging data is catalyzing a paradigm shift in which primary mood disord ers are conceptualized as illnesses that involve abnormalities of brain str ucture, as well as of brain function. These data suggest specific hypothese s regarding the neural mechanisms underlying pathological emotional process ing in mood disorders. They particularly support a role for dysfunction wit hin the prefrontal cortical and striatal systems that normally modulate lim bic and brainstem structures involved in mediating emotional behavior in th e pathogenesis of depressive symptoms.