Autonomic stress reactivity and executive functions in successful and unsuccessful criminal psychopaths from the community.

A significant gap in the psychopathy literature is the lack of studies comparing "successful," nonconvicted psychopaths with "unsuccessful," convicted psychopaths. This study tested the hypothesis that successful psychopaths show increased autonomic stress reactivity and better neuropsychological function compared with unsuccessful psychopaths. A total of 26 controls, 16 unsuccessful psychopaths, and 13 successful psychopaths were assessed on psychophysiological measures recorded during an emotional manipulation, the Wisconsin Card Sorting Test (WCST), Wechsler Memory Scale--Revised subtests, and childhood stressors. Compared with controls, unsuccessful psychopaths showed reduced cardiovascular stress reactivity. In contrast, successful psychopaths showed heightened reactivity, better WCST performance, and more parental absence than unsuccessful psychopaths and controls. The implications of these findings and the generalizability of existing psychopathy research are discussed.

Increased height and bulk in antisocial personality disorder and its subtypes.

Research suggests that those with antisocial tendencies are larger than controls, but studies have not assessed this association in antisocial personality disorder (APD) or its hypothesized sub-types (i.e. adolescence-limited, late-onset). Height, weight, body mass index, bulk, and psychosocial adversity were assessed in 44 controls, nine adolescent-limited antisocials, 21 APDs, and 13 late-onset antisocials from the community. Adult antisocial individuals, regardless of age of onset, were significantly taller and had greater body bulk than controls. Although groups tended to differ on weight, they did not differ on body mass index. In addition, APDs and adolescent-limited individuals reported greater psychosocial adversity than the other groups. Adversity did not account for height or bulk differences. Results suggest prior findings on height and bulk may apply to APD and support differentiating adolescent-limited and life-course persistent subgroups.

Elevated levels of cognitive-perceptual deficits in individuals with a family history of schizophrenia spectrum disorders.

This study finds that the relatives of schizophrenics have elevated scores on the cognitive-perceptual factor of the schizotypal personality questionnaire (SPQ), particularly for the 'unusual perceptual experiences' and 'ideas of reference' subscales. These results support recent findings by Kremen et al. (1998) and suggest that previous failures to demonstrate elevated scores on 'positive' symptoms of schizotypy may be a function of instrumentation.

Reduced prefrontal gray matter volume and reduced autonomic activity in antisocial personality disorder.

BACKGROUND: Major damage to gray and white matter in the prefrontal cortex and autonomic deficits have been found to result in pseudopsychopathic personality in patients with neurological disorders, but it is not known whether people with antisocial personality disorder (APD) in the community who do not have discernable brain trauma also have subtle prefrontal deficits. METHODS: Prefrontal gray and white matter volumes were assessed using structural magnetic resonance imaging in 21 community volunteers with APD (APD group) and in 2 control groups, comprising 34 healthy subjects (control group), 26 subjects with substance dependence (substance-dependent group), and 21 psychiatric controls. Autonomic activity (skin conductance and heart rate) was also assessed during a social stressor in which participants gave a videotaped speech on their faults. RESULTS: The APD group showed an 11.0% reduction in prefrontal gray matter volume in the absence of ostensible brain lesions and reduced autonomic activity during the stressor. These deficits predicted group membership independent of psychosocial risk factors. CONCLUSIONS: To our knowledge, these findings provide the first evidence for a structural brain deficit in APD. This prefrontal structural deficit may underlie the low arousal, poor fear conditioning, lack of conscience, and decision-making deficits that have been found to characterize antisocial, psychopathic behavior.

Skin-conductance orienting deficits and increased alcoholism in schizotypal criminals.

This study tested the interaction hypothesis that a subgroup of criminals with schizotypal personality would show skin-conductance orienting deficits and increased alcoholism. In a prospective, longitudinal study of alcoholism in 134 males, schizotypy was assessed during adolescence, skin-conductance orienting was assessed at ages 18-20 years, and criminal offending and alcohol abuse were assessed at ages 30-33 years. A significant interaction between schizotypy and criminality indicated that schizotypal criminals were characterized by autonomic orienting deficits. Furthermore, the rate of alcoholism in schizotypal criminals (54.8%) was significantly higher than in criminals (23.8%), schizotypal noncriminals (13.9%), and comparisons (21.7%). It is argued that schizotypal criminals are a relatively distinct group and that prefrontal dysfunction may underlie both orienting deficits and alcoholism in this group.

Reduced prefrontal and increased subcortical brain functioning assessed using positron emission tomography in predatory and affective murderers.

There appear to be no brain imaging studies investigating which brain mechanisms subserve affective, impulsive violence versus planned, predatory violence. It was hypothesized that affectively violent offenders would have lower prefrontal activity, higher subcortical activity, and reduced prefrontal/subcortical ratios relative to controls, while predatory violent offenders would show relatively normal brain functioning. Glucose metabolism was assessed using positron emission tomography in 41 comparisons, 15 predatory murderers, and nine affective murderers in left and right hemisphere prefrontal (medial and lateral) and subcortical (amygdala, midbrain, hippocampus, and thalamus) regions. Affective murderers relative to comparisons had lower left and right prefrontal functioning, higher right hemisphere subcortical functioning, and lower right hemisphere prefrontal/subcortical ratios. In contrast, predatory murderers had prefrontal functioning that was more equivalent to comparisons, while also having excessively high right subcortical activity. Results support the hypothesis that emotional, unplanned impulsive murderers are less able to regulate and control aggressive impulses generated from subcortical structures due to deficient prefrontal regulation. It is hypothesized that excessive subcortical activity predisposes to aggressive behaviour, but that while predatory murderers have sufficiently good prefrontal functioning to regulate these aggressive impulses, the affective murderers lack such prefrontal control over emotion regulation.

Prefrontal glucose deficits in murderers lacking psychosocial deprivation.

Previous research has suggested that links between autonomic nervous system functioning and violence are strongest in those who come from benign home backgrounds, but there appears to be no similar research using brain-imaging measures of central nervous system functioning. It was hypothesized that murderers who had no early psychosocial deprivation (e.g., no childhood abuse, family neglect) would demonstrate lower prefrontal glucose metabolism than murderers with early psychosocial deprivation and a group of normal controls. Murderers from a previous study, which showed prefrontal deficits in murderers, were assessed for psychosocial deprivation and divided into those with and without deprivation. Murderers without any clear psychosocial deficits were significantly lower on prefrontal glucose metabolism than murderers with psychosocial deficits and controls. These results suggest that murderers lacking psychosocial deficits are characterized by prefrontal deficits. It is argued that among violent offenders without deprived home backgrounds, the "social push" to violence is minimized, and consequently, brain abnormalities provide a relatively stronger predisposition to violence in this group.