Striatal brain volume linked to severity of substance use in high-risk incarcerated youth.

Substance use disorders among juveniles are a major public health concern and are often intertwined with other psychosocial risk factors including antisocial behavior. Identifying etiological risks and mechanisms promoting substance use disorders remains a high priority for informing more focused interventions in high-risk populations. The present study examined brain gray matter structure in relation to substance use severity among n = 152 high-risk, incarcerated boys (aged 14-20). Substance use severity was positively associated with gray matter volume across several frontal/striatal brain regions including amygdala, pallidum, putamen, insula, and orbitofrontal cortex. Effects were apparent when using voxel-based-morphometric analysis, as well as in whole-brain, data-driven, network-based approaches (source-based morphometry). These findings support the hypothesis that elevated gray matter volume in striatal reward circuits may be an endogenous marker for vulnerability to severe substance use behaviors among youth.

Clarifying Relations Between Core Features of Psychopathy and Substance (Mis)use: A Replication and Extension in Two Large Independent Samples.

Two studies examined the consistency of associations between specific components of psychopathy and two indices of drug use: (a) abstinence and (b) severity (i.e., counts) of lifetime substance use disorder (SUD) symptoms. Participants were 418 male county jail inmates in Illinois (Study One) and 354 male state prison inmates in New Mexico (Study Two). Across samples, lifestyle and antisocial trait ratings were associated with a reduced likelihood of abstinence from most substances. Lifestyle traits were also uniquely associated with severity of substance dependence ratings. Consistent with prior research, interpersonal traits were uniquely related to cocaine indices in both samples. Furthermore, analyses revealed negative associations between the affective features of psychopathy and alcohol dependence in one sample (Study Two), and illicit substance use across samples. These findings demonstrate the robustness of the associations between the interpersonal and affective features of psychopathy and specific aspects of substance (mis)use.

Clarifying the relationship between mental illness and recidivism using machine learning: A retrospective study.

OBJECTIVE: There is currently inconclusive evidence regarding the relationship between recidivism and mental illness. This retrospective study aimed to use rigorous machine learning methods to understand the unique predictive utility of mental illness for recidivism in a general population (i.e.; not only those with mental illness) prison sample in the United States. METHOD: Participants were adult men (n = 322) and women (n = 72) who were recruited from three prisons in the Midwest region of the United States. Three model comparisons using Bayesian correlated t-tests were conducted to understand the incremental predictive utility of mental illness, substance use, and crime and demographic variables for recidivism prediction. Three classification statistical algorithms were considered while evaluating model configurations for the t-tests: elastic net logistic regression (GLMnet), k-nearest neighbors (KNN), and random forests (RF). RESULTS: Rates of substance use disorders were particularly high in our sample (86.29%). Mental illness variables and substance use variables did not add predictive utility for recidivism prediction over and above crime and demographic variables. Exploratory analyses comparing the crime and demographic, substance use, and mental illness feature sets to null models found that only the crime and demographics model had an increased likelihood of improving recidivism prediction accuracy. CONCLUSIONS: Despite not finding a direct relationship between mental illness and recidivism, treatment of mental illness in incarcerated populations is still essential due to the high rates of mental illnesses, the legal imperative, the possibility of decreasing institutional disciplinary burden, the opportunity to increase the effectiveness of rehabilitation programs in prison, and the potential to improve meaningful outcomes beyond recidivism following release.

Psychopathy Scores Predict Recidivism in High-risk Youth: A Five-year Follow-up Study.

Psychopathic traits have been associated with rearrest in adolescents involved in the criminal legal system. Much of the prior work has focused on White samples, short follow-up windows, and relatively low-risk youth. The current study aimed to evaluate the utility of the Hare Psychopathy Checklist: Youth Version (PCL:YV) for predicting general and violent felony recidivism in a large sample of high-risk, predominantly Hispanic/Latino, male adolescents (n = 254) with a five-year follow-up period. Results indicated higher PCL:YV scores and lower full-scale estimated IQ scores were significantly associated with a shorter time to felony and violent felony rearrest. These effects generalized to Hispanic/Latino adolescents (n = 193)-a group that faces disproportionate risk of being detained or committed to juvenile correctional facilities in the U.S. These results suggest that expert-rated measures of psychopathic traits and IQ are reliable predictors of subsequent felony and violent felony rearrest among high-risk male adolescents.

Examining the Association between Psychopathic Traits and Fearlessness among Maximum-Security Incarcerated Male Adolescents.

Studies have reported positive associations between youth psychopathy scores and measures of 'fearlessness'. However, prior studies modified fearlessness items to be age appropriate, shifting from assessing hypothetical, extreme forms of physical risk-taking (e.g., flying an airplane) to normative risk-taking (e.g., riding bicycles downhill). We hypothesize that associations between youth psychopathy scores and alternative forms of sensation seeking (i.e., Disinhibition) have been conflated under a false fearlessness label. We tested this hypothesis among incarcerated male adolescents, investigating whether youth psychopathy scores were significantly associated with two different forms of sensation seeking: Disinhibition and Thrill and Adventure Seeking (TAS). Youth psychopathic traits were assessed using the Psychopathy Checklist: Youth Version (PCL:YV), Antisocial Process Screening Device (APSD), Child Psychopathy Scale (CPS), Inventory of Callous and Unemotional Traits (ICU), and Youth Psychopathic Traits Inventory (YPI). Disinhibition and fearlessness (i.e., TAS) were assessed using an unmodified version of the Zuckerman Sensation Seeking Scales (SSS). Consistent with hypotheses, youth psychopathy scores were associated with higher Disinhibition and lower TAS scores. Our results contribute to a growing body of literature suggesting that psychopathic traits, including among adolescents, are not concomitant with physical risk-taking and descriptions of psychopathy including fearlessness distort a precise understanding of psychopathy's core features.

Automated patterns of head dynamics are associated with psychopathic traits in incarcerated women.

Men with elevated psychopathic traits have been characterized by unique patterns of nonverbal communication, including more fixed and focused head positions during clinical interviews, compared to men scoring low on measures of psychopathy. However, it is unclear whether similar patterns of head dynamics help characterize women scoring high on psychopathic traits. Here, we utilized an automated detection algorithm to assess head position and dynamics during a videotaped clinical interview (i.e., the Psychopathy Checklist - Revised [PCL-R]) in a sample of n = 213 incarcerated women. PCL-R Total, Factor 1 (i.e., interpersonal and affective psychopathic traits), and Factor 2 (i.e., lifestyle/behavioral and antisocial/developmental psychopathic traits) scores were associated with a pattern of head dynamics indicative of a rigid head position. The current study extends analyses of nonverbal behavior studies in men to women and highlights how individuals with elevated psychopathic traits demonstrate unique nonverbal behaviors relative to individuals who score low on psychopathic traits. The implications and clinical value of these findings are discussed.

Psychometric properties of the Trauma Checklist 2.0 and its predictive utility of felony re-offending among high-risk juvenile offenders.

BACKGROUND: Incarcerated youth are characterized by particularly high rates of childhood trauma, a significant risk factor for outcomes including risky behaviors and recidivism. Trauma-based interventions can ameliorate the negative effects of childhood trauma; however, a critical part of success is careful trauma screening. Due to the limitations associated with commonly used self-report trauma assessments, our team developed the Trauma Checklist (TCL), a trained-rater assessment of childhood trauma specifically created for use with forensic populations. The TCL is designed to provide a more comprehensive assessment of trauma, incorporating categories that are of specific relevance for incarcerated individuals (e.g., traumatic loss). Here, we discuss the continued development made to our original trauma assessment and explore the psychometric properties of this expanded assessment (herein termed the TCL 2.0). METHOD: We examined relationships between TCL 2.0 scores, measures of psychopathology, and psychopathic traits in a sample of incarcerated male juvenile offenders (n = 237). In addition, we examined whether TCL 2.0 scores were associated with time to felony re-offense via Cox proportional-hazard regression analyses. RESULTS: We examined dimensionality of the TCL 2.0 using a principal component analysis (PCA), the results of which were confirmed via exploratory structural equation modeling; the PCA yielded a two-component solution (i.e., PC1 and PC2). We observed that PC1 (Experienced Trauma) scores were positively correlated with mood disorder diagnoses. TCL 2.0 total scores were positively correlated with post-traumatic stress disorder symptomatology and psychopathic traits. Finally, higher PC2 (Community Trauma) scores were associated with faster time to felony re-offending. CONCLUSIONS: These results suggest that the TCL 2.0 may be a beneficial screening tool to provide high-risk youth with appropriate trauma-informed treatment.

Psychopathic traits and altered resting-state functional connectivity in incarcerated adolescent girls.

Previous work in incarcerated boys and adult men and women suggest that individuals scoring high on psychopathic traits show altered resting-state limbic/paralimbic, and default mode functional network properties. However, it is unclear whether similar results extend to high-risk adolescent girls with elevated psychopathic traits. This study examined whether psychopathic traits [assessed via the Hare Psychopathy Checklist: Youth Version (PCL:YV)] were associated with altered inter-network connectivity, intra-network connectivity (i.e., functional coherence within a network), and amplitude of low-frequency fluctuations (ALFFs) across resting-state networks among high-risk incarcerated adolescent girls (n = 40). Resting-state networks were identified by applying group independent component analysis (ICA) to resting-state fMRI scans, and a priori regions of interest included limbic, paralimbic, and default mode network components. We tested the association of psychopathic traits (PCL:YV Factor 1 measuring affective/interpersonal traits and PCL:YV Factor 2 assessing antisocial/lifestyle traits) to these three resting-state measures. PCL:YV Factor 1 scores were associated with increased low-frequency and decreased high-frequency fluctuations in components corresponding to the default mode network, as well as increased intra-network FNC in components corresponding to cognitive control networks. PCL:YV Factor 2 scores were associated with increased low-frequency fluctuations in sensorimotor networks and decreased high-frequency fluctuations in default mode, sensorimotor, and visual networks. Consistent with previous analyses in incarcerated adult women, our results suggest that psychopathic traits among incarcerated adolescent girls are associated with altered intra-network ALFFs-primarily that of increased low-frequency and decreased high-frequency fluctuations-and connectivity across multiple networks including paralimbic regions. These results suggest stable neurobiological correlates of psychopathic traits among women across development.

Impaired salience network switching in psychopathy.

Growing evidence suggests that psychopathy is related to altered connectivity within and between three large-scale brain networks that support core cognitive functions, including allocation of attention. In healthy individuals, default mode network (DMN) is involved in internally-focused attention and cognition such as self-reference. Frontoparietal network (FPN) is anticorrelated with DMN and is involved in externally-focused attention to cognitively demanding tasks. A third network, salience network (SN), is involved in detecting salient cues and, crucially, appears to play a role in switching between the two anticorrelated networks, DMN and FPN, to efficiently allocate attentional resources. Psychopathy has been related to reduced anticorrelation between DMN and FPN, suggesting SN's role in switching between these two networks may be diminished in the disorder. To test this hypothesis, we used independent component analysis to derive DMN, FPN, and SN activity in resting-state fMRI data in a sample of incarcerated men (N = 148). We entered the activity of the three networks into dynamic causal modeling to test SN's switching role. The previously established switching effect of SN among young, healthy adults was replicated in a group of low psychopathy participants (posterior model probability = 0.38). As predicted, SN's switching role was significantly diminished in high psychopathy participants (t(145) = 26.39, p < .001). These findings corroborate a novel theory of brain function in psychopathy. Future studies may use this model to test whether disrupted SN switching is related to high psychopathy individuals' abnormal allocation of attention.

Machine learning classification of chronic traumatic brain injury using diffusion tensor imaging and NODDI: A replication and extension study.

Individuals with acute and chronic traumatic brain injury (TBI) are associated with unique white matter (WM) structural abnormalities, including fractional anisotropy (FA) differences. Our research group previously used FA as a feature in a linear support vector machine (SVM) pattern classifier, observing high classification between individuals with and without acute TBI (i.e., an area under the curve [AUC] value of 75.50%). However, it is not known whether FA could similarly classify between individuals with and without history of chronic TBI. Here, we attempted to replicate our previous work with a new sample, investigating whether FA could similarly classify between incarcerated men with (n = 80) and without (n = 80) self-reported history of chronic TBI. Additionally, given limitations associated with FA, including underestimation of FA values in WM tracts containing crossing fibers, we extended upon our previous study by incorporating neurite orientation dispersion and density imaging (NODDI) metrics, including orientation dispersion (ODI) and isotropic volume (Viso). A linear SVM based classification approach, similar to our previous study, was incorporated here to classify between individuals with and without self-reported chronic TBI using FA and NODDI metrics as separate features. Overall classification rates were similar when incorporating FA and NODDI ODI metrics as features (AUC: 82.50%). Additionally, NODDI-based metrics provided the highest sensitivity (ODI: 85.00%) and specificity (Viso: 82.50%) rates. The current study serves as a replication and extension of our previous study, observing that multiple diffusion MRI metrics can reliably classify between individuals with and without self-reported history of chronic TBI.

Traumatic Brain Injury and Psychopathic Traits in Justice-Involved Adult Women.

Studies have documented associations between traumatic brain injury (TBI) and mental disorders. The relationship between psychopathic personality and TBI remains poorly understood, though both are associated with similar characteristics (e.g., low empathy, aggression, disturbances in social/moral behavior). Yet, it is not clear whether assessment of psychopathic features is influenced by presence versus absence of TBI, and which aspects of TBI may be associated with psychopathic traits. This study examined the psychopathy-TBI association in justice-involved women (N = 341) with structural equation modeling. We tested if measurement invariance of psychopathic traits was evident among those with versus without TBI and which TBI variables (number, severity, age at first TBI) predicted psychopathic features in conjunction with symptoms of psychopathology, IQ, and age. Results provided evidence of measurement invariance, and more women with TBI, compared to those without, met criteria for psychopathy. Younger age of TBI and TBI severity predicted interpersonal-affective psychopathic features.

Emotional intelligence in incarcerated sexual offenders with sexual sadism.

Emotional intelligence (EI) is defined by the ability to perceive, manage, and reason about emotions in oneself and others. Studies have reported deficits in EI abilities among certain antisocial populations such as individuals with psychopathy, and enhanced performance among sexual offenders. Despite EI's relevance to offending behaviour, the association between EI and paraphilic offending has been under-studied. We examined the association between EI, sexual offending, and sexual sadism in 80 incarcerated men with sexual offenses and 207 incarcerated men with non-sexual offences. EI was assessed using the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT). Sadism was measured using the Severe Sexual Sadism Scale (SeSaS). Results showed that SeSaS scores were positively associated with Strategic EI (the ability to understand and manage emotions), but were not significantly related to Experiential EI. This may reflect core characteristics of sexual sadism including domination and manipulation, challenging the prevalent notion that higher EI is invariably positive.

Aberrant resting-state functional connectivity associated with childhood trauma among juvenile offenders.

Individuals with history of childhood trauma are characterized by aberrant resting-state limbic and paralimbic functional network connectivity. However, it is unclear whether specific subtypes of trauma (i.e., experienced vs observed or community) showcase differential effects. This study examined whether subtypes of childhood trauma (assessed via the Trauma Checklist [TCL] 2.0) were associated with aberrant intra-network amplitude of fluctuations and connectivity (i.e., functional coherence within a network), and inter-network connectivity across resting-state networks among incarcerated juvenile males (n = 179). Subtypes of trauma were established via principal component analysis of the TCL 2.0 and resting-state networks were identified by applying group independent component analysis to resting-state fMRI scans. We tested the association of subtypes of childhood trauma (i.e., TCL Factor 1 measuring experienced trauma and TCL Factor 2 assessing community trauma), and TCL Total scores to the aforementioned functional connectivity measures. TCL Factor 2 scores were associated with increased high-frequency fluctuations and increased intra-network connectivity in cognitive control, auditory, and sensorimotor networks, occurring primarily in paralimbic regions. TCL Total scores exhibited similar neurobiological patterns to TCL Factor 2 scores (with the addition of aberrant intra-network connectivity in visual networks), and no significant associations were found for TCL Factor 1. Consistent with previous analyses of community samples, our results suggest that childhood trauma among incarcerated juvenile males is associated with aberrant intra-network amplitude of fluctuations and connectivity across multiple networks including predominately paralimbic regions. Our results highlight the importance of accounting for traumatic loss, observed trauma, and community trauma in assessing neurobiological aberrances associated with adverse experiences in childhood, as well as the value of trained-rater trauma assessments compared to self-report.

Psychopathic Traits Are Associated with Lifetime History of Nicotine Dependence among Incarcerated Offenders.

Background: Individuals scoring high on psychopathy engage in problematic patterns of alcohol and illicit substance use. However, our understanding regarding the association between psychopathy and nicotine use remains limited, which is surprising, given the detrimental consequences associated with such use. Previous studies have observed significant correlations between psychopathic traits (particularly Factor 2 scores assessing lifestyle/behavioral and antisocial traits from the Psychopathy Checklist - Revised [PCL-R]) and increased frequency of nicotine use. However, no study has investigated whether individuals scoring high on psychopathy are characterized by problematic patterns of nicotine use, including lifetime history of nicotine dependence.Objectives: The current study aimed to address this gap, specifically investigating whether PCL-R scores were associated with higher total scores from the Fagerström Test for Nicotine Dependence (FTND).Results: Across both incarcerated men and women, PCL-R total, Factor 2, and Facet 3 (measuring lifestyle/behavioral psychopathic traits) scores were positively correlated with FTND total scores. Additionally, across both samples, hierarchical linear regression analyses revealed these same psychopathy scores remained associated with higher FTND total scores when controlling for additional covariate measures (e.g., age, severity of alcohol and illicit substance use, race, ethnicity, and IQ).Conclusions/Importance: Though associated with small effect sizes, our results support the notion that lifestyle/behavioral psychopathic traits represent a general risk factor for engaging in risky behavior associated with deleterious health consequences, including nicotine use. Our results hold implications for the development of treatment approaches, designed to reduce problematic levels of substance use among individuals scoring high on psychopathy.

Psychopathy and substance use predict recidivism in women: A 7-year prospective study.

Recidivism places a significant burden on society and efforts aimed at reducing cyclical criminal justice involvement are needed. This prospective study tested the utility of psychopathic traits in predicting general, felony, and substance-related rearrest in women following release from a correctional facility. The extent to which psychopathic traits offered incremental utility in predicting outcomes, above and beyond other established risk factors, including substance use disorder, was examined. Participants included 327 incarcerated adult women who completed comprehensive clinical and psychiatric assessments prior to release from correctional facilities. Psychopathic traits and lifetime substance use disorder were measured using the Hare Psychopathy Checklist-Revised (PCL-R) and Structured Clinical Interview for DSM-IV-TR Axis I Disorders, respectively. Results showed that general, felony, and substance-related rearrest following institutional release were associated with higher PCL-R Factor 2 scores, assessing lifestyle/behavioral and antisocial/developmental psychopathic traits. Additionally, when controlling for other risk factors associated with recidivism, including age at release, number of prior adult prison terms, and substance use disorder, higher PCL-R Factor 2 scores remained significantly associated with rearrest outcomes in women. Findings inform risk prediction and treatment efforts aimed at reducing recidivism in justice-involved women. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Hemodynamic activity in the limbic system predicts reoffending in women.

Previous research (Aharoni et al., 2013, 2014) found that hemodynamic activity in the dorsal anterior cingulate cortex (dACC) during error monitoring predicted non-violent felony rearrest in men released from prison. This article reports an extension of the Aharoni et al. (2013, 2014) model in a sample of women released from state prison (n = 248). Replicating aspects of prior work, error monitoring activity in the dACC, as well as psychopathy scores and age at release, predicted non-violent felony rearrest in women. Sex differences in the directionality of dACC activity were observed-high error monitoring activity predicted rearrest in women, whereas prior work found low error monitoring activity predicted rearrest in men. As in prior analyses, the ability of the dACC to predict rearrest outcomes declines with more generalized outcomes (i.e., general felony). Implications for future research and clinical and forensic risk assessment are discussed.

ANKK1 and TH gene variants in combination with paternal maltreatment increase susceptibility to both cognitive and attentive impulsivity.

Recent scientific findings suggest that dopamine exerts a central role on impulsivity, as well as that aversive life experiences may promote the high levels of impulsivity that often underlie violent behavior. To deepen our understanding of the complex gene by environment interplay on impulsive behavior, we genotyped six dopaminergic allelic variants (ANKK1-rs1800497, TH-rs6356, DRD4-rs1800955, DRD4-exonIII-VNTR, SLC6A3-VNTR and COMT-rs4680) in 655 US White male inmates convicted for violent crimes, whose impulsivity was assessed by BIS-11 (Barratt Impulsiveness Scale). Furthermore, in a subsample of 216 inmates from the whole group, we also explored the potential interplay between the genotyped dopaminergic variants and parental maltreatment measured by MOPS (Measure of Parental Style) in promoting impulsivity. We found a significant interaction among paternal MOPS scores, ANKK1-rs1800497-T allele and TH-rs6356-A allele, which increased the variance of BIS-11 cognitive/attentive scores explained by paternal maltreatment from 1.8 up to 20.5%. No direct association between any of the individual genetic variants and impulsivity was observed. Our data suggest that paternal maltreatment increases the risk of attentive/cognitive impulsivity and that this risk is higher in carriers of specific dopaminergic alleles that potentiate the dopaminergic neurotransmission. These findings add further evidence to the mutual role that genetics and early environmental factors exert in modulating human behavior and highlight the importance of childhood care interventions.

Correlates of externalizing psychopathology in incarcerated men.

Externalizing traits are extremely costly for society and disproportionately prevalent among incarcerated individuals. The Hierarchical Taxonomy of Psychopathology (HiTOP) is an empirically derived classification system that approaches psychopathology dimensionally and was developed in response to critiques of current diagnostic classification systems. The Externalizing Spectrum Inventory-100 item version (ESI-100) is an assessment of externalizing problems that fits within the HiTOP framework and characterizes dimensional externalizing traits. The present study aimed to replicate prior research examining the convergent validity of the ESI Total Score by examining associations with psychopathy, conduct disorder, and substance use among incarcerated males. A total of 1,808 participants had ESI-100 data, although sample sizes across criterion measures varied. The majority of results replicated relationships between the ESI 159-item version and externalizing disorders and negative emotionality. Less is known about the dimensional relationships between externalizing traits as measured by the ESI-100 and internalizing disorders and symptoms, and other correlates of externalizing. The study extended previous results by examining associations between the ESI-100 and internalizing disorders, impulsivity, childhood trauma, and emotion regulation (ER) as a test of discriminant validity. Analyses revealed associations between the ESI-100 and childhood trauma, impulsivity, emotion regulation difficulties, and symptoms (but not diagnoses) of internalizing disorders. These results enhance our understanding of dimensional traits of externalizing and suggest nuanced relationships between externalizing and internalizing traits. Results have important implications (e.g., transdiagnostic treatment targets) for treatment of mental health disorders by highlighting the importance of cross-diagnostic treatment approaches. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

An examination of autonomic and facial responses to prototypical facial emotion expressions in psychopathy.

Meta-analyses have found that people high in psychopathy categorize (or "recognize") others' prototypical facial emotion expressions with reduced accuracy. However, these have been contested with remaining questions regarding the strength, specificity, and mechanisms of this ability in psychopathy. In addition, few studies have tested holistically whether psychopathy is related to reduced facial mimicry or autonomic arousal in response to others' dynamic facial expressions. Therefore, the current study presented 6 s videos of a target person making prototypical emotion expressions (anger, fear, disgust, sadness, joy, and neutral) to N = 88 incarcerated adult males while recording facial electromyography, skin conductance response (SCR), and heart rate. Participants identified the emotion category and rated the valence and intensity of the target person's emotion. Psychopathy was assessed via the Psychopathy Checklist-Revised (PCL-R). We predicted that overall PCL-R scores and scores for the interpersonal/affective traits, in particular, would be related to reduced emotion categorization accuracy, valence ratings, intensity ratings, facial mimicry, SCR amplitude, and cardiac deceleration in response to the prototypical facial emotion expressions. In contrast to our hypotheses, PCL-R scores were unrelated to emotion categorization accuracy, valence ratings, and intensity ratings. Stimuli failed to elicit facial mimicry from the full sample, which does not allow drawing conclusions about the relationship between psychopathy and facial mimicry. However, participants displayed general autonomic arousal responses, but not to prototypical emotion expressions per se. PCL-R scores were also unrelated to SCR and cardiac deceleration. These findings failed to identify aberrant behavioral and physiological responses to prototypical facial emotion expressions in relation to psychopathy.

HTR1B genotype and psychopathy: Main effect and interaction with paternal maltreatment.

Psychopathy is a condition characterized by atypical emotions and socially maladaptive behavioral patterns. Among incarcerated people, psychopathy has been associated with higher rates of crimes, recidivism, and resistance to treatment. Many studies have indicated significant heritability of psychopathic traits, but little is known about the specific contribution of genes and their interaction with adverse experiences in life. Considering the primary role that serotonin plays in cognition and emotion, we investigated TPH2-rs4570625, 5-HTTLPR, MAOA-uVNTR, HTR1B-rs13212041 and HTR2A-rs6314 as risk factors for psychopathy in the largest sample of institutionalized individuals studied so far, consisting of 793 US White male incarcerated adults, and in a replication sample of 168 US White male incarcerated adolescents. In a subgroup of the adult sample, the interaction between genetics and parenting style, assessed by the Measure of Parental Style (MOPS) questionnaire, was also evaluated. The HTR1B-rs13212041-T/T genotype, as compared to HTR1B-rs13212041-C allele, predicted higher psychopathy scores in both the adult and the adolescent samples. The interaction between HTR1B-rs13212041-T/T genotype and paternal MOPS scores, investigated in a subgroup of the adult sample, was an even stronger predictor of higher levels of psychopathy than either the genetics or the environment taken individually. Overall, these data, obtained in two independent samples, shed new light on neurobiological correlates of psychopathy with promising implications both at a clinical and forensic level.