Neural correlates of impulsivity factors in psychiatric patients and healthy volunteers: a voxel-based morphometry study.

According to bottom-up/top-down models, impulsivity facets are represented across the cerebral cortex and subcortex. Hypothesized gray matter correlates of motor, attentional and non-planning impulsivity were examined in groups of 35 psychiatric patients characterized by self-control problems and 18 healthy volunteers. Among patients, a positive correlation was found between motor impulsivity and the right cerebellum, and a negative correlation emerged between attentional impulsivity and the left lateral orbitofrontal cortex (OFC). Among controls, attentional and motor impulsivity correlated negatively with the left superior temporal gyrus, while non-planning impulsivity correlated positively with the left OFC and lateral frontopolar cortex. Follow-up analyses revealed convergence in correlation patterns from patients to controls, but not vice versa. That pattern suggested broader neural representation of the trait in the healthy controls, who were less impulsive than the psychiatric patients.