A functional magnetic resonance imaging study of emotional Stroop in euthymic bipolar disorder

Bipolar disorder is regarded as a disorder of mood and initial studies have focused on structural abnormalities in limbic networks, known to subserve mood. More recently, functional imaging studies allude to affect processing deficits, which may involve frontostriatal networks. This study sought to explore disturbances in networks involved in the processing of negative affect in euthymic bipolar patients. We used simultaneous functional magnetic resonance imaging and galvanic skin responsivity to explore disturbances in these networks. When processing negative affect, controls recruited a distributed subcortical-prefrontal network. In contrast, patients could only activate a subcortical network that included the amygdala and hippocampus. This study provides evidence for a disconnection in the transfer of information within frontostriatal networks in bipolar disorder.