It has been suggested that impulsivity and aggression are associated w
ith neuropsychiatric impairment. Neurological soft signs may be a usef
ul marker of nonspecific brain damage, and may therefore be increased
in impulsive and aggressive patients compared with normal control subj
ects. A structured examination was used to evaluate neurological soft
signs in 28 patients with personality disorders characterized by impul
sivity and 28 healthy control subjects. All of the patients met DSM-II
I-R criteria for borderline personality disorder, and 10 also met crit
eria for antisocial personality disorder. All patients were questioned
about past history of physical aggression, and a subset of 18 patient
s underwent neuropsychological testing with a select battery. Left-sid
ed neurological soft signs were significantly increased in patients co
mpared with normal control subjects. Patients with a history of aggres
sion, however, had significantly more right-sided neurological soft si
gns than those without a history of aggression. Increased neurological
soft signs were associated with impairment on the Wisconsin Card Sort
, a test of frontal lobe executive function. Specific neuropsychiatric
abnormalities, such as lateralized neurological soft signs and associ
ated impairment on select neuropsychological tests, may be present in
patients with personality disorders characterized by impulsivity.