Evidence for frontal-subcortical circuit abnormalities in bipolar affective disorder.

Most of the literature on bipolar disorder has focused on abnormalities of neurotransmitters rather than brain circuits. The few discussions of circuits have primarily focused on the limbic system. Evidence is accumulating, however, that basal ganglia-thalamic-cortical reentrant circuits play a major role in the affective, motor and cognitive symptoms of a number of neuropsychiatric conditions including bipolar disorder. In this paper, the authors argue that there is compelling direct and indirect evidence of frontal-subcortical circuit abnormalities in patients with bipolar affective disorder.