Psychopaths impose large costs on society, as they are frequently habitual, violent criminals. The pervasive nature of emotional and behavioral symptoms in psychopathy suggests that several associated brain regions may contribute to the disorder. Studies employing a variety of methods have converged on a set of brain regions in paralimbic cortex and limbic areas that appear to be dysfunctional in psychopathy. The present study further tests this hypothesis by investigating structural abnormalities using voxel-based morphometry in a sample of incarcerated men (N [H11005] 296). Psychopathy was associated with decreased regional gray matter in several paralimbic and limbic areas, including bilateral parahippocampal, amygdala, and hippocampal regions, bilateral temporal pole, posterior cingulate cortex, and orbitofrontal cortex. The consistent identification of paralimbic cortex and limbic structures in psychopathy across diverse methodologies strengthens the interpretation that these regions are crucial for understanding neural dysfunction in psychopathy.

Objective To investigate the relationship between brain structure and psychopathic traits in maximum-security incarcerated male adolescents: Do the associations between brain volumes in paralimbic and limbic regions and psychopathic traits observed in incarcerated adult men extend to an independent sample of incarcerated male adolescents? Method A structural magnetic resonance imaging (MRI) study of regional gray matter volumes (GMV) by using voxel-based morphometry (VBM) in maximum-security incarcerated male adolescents (N=218) assessed for psychopathic traits using the Hare Psychopathy Checklist–Youth Version (PCL-YV). All analyses controlled for effects of age, substance use, and brain size. Results Consistent with hypotheses and the adult literature, psychopathic traits were associated with decreased regional GMV in diffuse paralimbic regions, including orbitofrontal cortex, bilateral temporal poles, and posterior cingulate cortex. Conclusions These results strengthen the interpretation that paralimbic regions are central for understanding neural dysfunction associated with psychopathic traits and that psychopathy is best conceptualized as a neurodevelopmental disorder.

Importance Marijuana use may alter ventral striatal response to reward, which may heighten susceptibility to substance use disorder (SUD). Cross-sectional studies have reported either increased ventral striatal response to reward or no difference in marijuana users compared with controls. Longitudinal research is needed to resolve the inconsistencies and disentangle preexisting susceptibility from the effects of marijuana use on neural function involved in reward responding. Objective To determine whether marijuana use among young adults prospectively impacts nucleus accumbens (NAcc) activation during reward anticipation. Design Longitudinal study of self-report marijuana use and brain function using functional magnetic resonance imaging (fMRI) at three consecutive time points. Setting Data were obtained from young adult participants in the Michigan Longitudinal Study, an ongoing, prospective study of youth at high risk for SUD and a contrast sample of control families. Participants The sample consisted of 108 young adults (36% female; 78% family history of SUD) who underwent three fMRI scans at approximately age 20 (time 1), 22 (time 2), and 24 (time 3). Main Outcome and Measures We investigated the impact of marijuana use on neural response in the NAcc to reward anticipation during a monetary incentive delay task (MIDT) using a cross-lagged model. Covariates for analyses included sex, age at first scan, family history of SUD, prior marijuana use, and binge drinking (prior and concurrent). This model was also tested separately with the inclusion of cigarette smoking. Results Greater marijuana use was associated with later blunted activation in the NAcc during reward anticipation (time 1 to time 2: β=−0.26, P=0.04; time 2 to time 3: β=−0.25, P=0.01). When we tested the cross-lagged model with the inclusion of prior and concurrent cigarette use, the impact of marijuana use from time 2 to time 3 remained significant and the effect of cigarette use was non-significant. Conclusions and Relevance Our findings indicate that marijuana use is associated with decreased neural response in the NAcc during the anticipation of non-drug rewards. Over time, marijuana use may alter anticipatory reward processing in the NAcc, which may increase risk for continued drug use and later addiction.

Rates of alcohol and other drug use rise sharply throughout adolescence and peak in the early 20s. Likewise, prevalence of first-time substance use disorder (SUD) and past-year SUD both peak between ages 18–23. SUD is associated with a host of negative outcomes and is a serious health concern. Understanding the mechanisms that precede the onset and escalation of substance use is crucial in order to develop more effective prevention and intervention strategies for children and adolescents at risk for SUD. In this review, we discuss recent findings from functional neuroimaging studies in children, adolescents, and emerging adults that focus on uncovering the neural underpinnings of SUD risk. The focus is on inhibitory control and reward circuitry due to their involvement in risk-taking behaviors, which are heightened in adolescence and may facilitate substance use. We discuss convergences in the literature and highlight findings suggesting that the association between SUD risk and neurofunctioning may be moderated by age, gender, and history of substance use. Recommendations for future directions are also discussed.

Psychopathy is believed to be associated with brain abnormalities in both paralimbic (i.e., orbitofrontal cortex, insula, temporal pole, parahippocampal gyrus, posterior cingulate) and limbic (i.e., amygdala, hippocampus, anterior cingulate) regions. Recent structural imaging studies in both community and prison samples are beginning to support this view. Sixty six participants, recruited from community corrections centers, were administered the Hare Psychopathy Checklist Revised (PCL R), and underwent magnetic resonance imaging (MRI). Voxel based morphometry was used to test the hypothesis that psychopathic traits would be associated with gray matter reductions in limbic and paralimbic regions. Effects of lifetime drug and alcohol use on gray matter volume were covaried. Psychopathic traits were negatively associated with gray matter volumes in right insula and right hippocampus. Additionally, psychopathic traits were positively associated with gray matter volumes in bilateral orbital frontal cortex and right anterior cingulate. Exploratory regression analyses indicated that gray matter volumes within right hippocampus and left orbital frontal cortex combined to explain 21.8% of the variance in psychopathy scores. These results support the notion that psychopathic traits are associated with abnormal limbic and paralimbic gray matter volume. Furthermore, gray matter increases in areas shown to be functionally impaired suggests that the structure function relationship may be more nuanced than previously thought.

Psychopathy-related paralimbic and limbic structural brain abnormalities have been implicated in incarcerated adult and adolescent male samples. However, there have been few neuroimaging studies of psychopathic traits in females in general and no studies from incarcerated female youth in particular. Here we present the first study to examine the relationship between brain gray matter volumes and psychopathic traits (assessed using the Psychopathy Checklist-Youth Version [PCL-YV]) in a sample of maximum-security incarcerated female adolescents (N = 39; mean age = 17.6 years). Consistent with male samples, regional gray matter volumes were negatively related to psychopathic traits in female youth offenders in limbic and paralimbic areas, including orbitofrontal cortex, parahippocampal cortex, temporal poles, and left hippocampus. These results provide evidence that psychopathic traits manifest similar neural abnormalities across sex and age.

Recent neuroscientific evidence indicates that psychopathy is associated with abnormal function and structure in limbic and paralimbic areas. Psychopathy and substance use disorders are highly comorbid, but clinical experience suggests that psychopaths abuse drugs for different reasons than non-psychopaths, and that psychopaths do not typically experience withdrawal and craving upon becoming incarcerated. These neurobiological abnormalities may be related to psychopaths' different motivations for—and symptoms of—drug use. This study examined the modulatory effect of psychopathic traits on the neurobiological craving response to pictorial drug stimuli. Drug-related pictures and neutral pictures were presented and rated by participants while hemodynamic activity was monitored using functional magnetic resonance imaging. These data were collected at two correctional facilities in New Mexico using the Mind Research Network mobile magnetic resonance imaging system. The sample comprised 137 incarcerated adult males and females (93 females) with histories of substance dependence. The outcome of interest was the relation between psychopathy scores (using the Hare Psychopathy Checklist-Revised) and hemodynamic activity associated with viewing drug-related pictures vs. neutral pictures. There was a negative association between psychopathy scores and hemodynamic activity for viewing drug-related cues in the anterior cingulate, posterior cingulate, hippocampus, amygdala, caudate, globus pallidus, and parts of the prefrontal cortex. Psychopathic traits modulate the neurobiological craving response and suggest that individual differences are important for understanding and treating substance abuse.

BackgroundViolence that leads to homicide results in an extreme financial and emotional burden on society. Juveniles who commit homicide are often tried in adult court and typically spend the majority of their lives in prison. Despite the enormous costs associated with homicidal behavior, there have been no serious neuroscientific studies examining youth who commit homicide.MethodsHere we use neuroimaging and voxel-based morphometry to examine brain gray matter in incarcerated male adolescents who committed homicide (n = 20) compared with incarcerated offenders who did not commit homicide (n = 135). Two additional control groups were used to understand further the nature of gray matter differences: incarcerated offenders who did not commit homicide matched on important demographic and psychometric variables (n = 20) and healthy participants from the community (n = 21).ResultsCompared with incarcerated adolescents who did not commit homicide (n = 135), incarcerated homicide offenders had reduced gray matter volumes in the medial and lateral temporal lobes, including the hippocampus and posterior insula. Feature selection and support vector machine learning classified offenders into the homicide and non-homicide groups with 81% overall accuracy.ConclusionsOur results indicate that brain structural differences may help identify those at the highest risk for committing serious violent offenses.