Neurotransmitter system dysfunction may contribute to the borderline person
ality disorder traits of impulsive aggression and affective instability. Th
is article reviews evidence from neurochemical assays, receptor-density stu
dies, neuroendocrine-challenge paradigms, functional neuroimaging studies,
and candidate-gene research, which converge to identify particular neurotra
nsmitter systems that seem to be dysregulated in patients with borderline p
ersonality disorder.