Youth with elevated psychopathic traits exhibit structural integrity deficits in the uncinate fasciculus

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.

Quantitative Head Dynamics Associated with Interpersonal (Grandiose-Manipulative) Psychopathic Traits in Incarcerated Youth

Clinicians have long noted that individuals with elevated psychopathic traits can be characterized by unique interpersonal styles, including prolonged eye contact, invasion of interpersonal space, and frequent use of hand gestures. Such forms of nonverbal communication can be measured via hand, body, and head position and dynamics. Previous studies have developed an automated algorithm designed to capture head position and dynamics from digital recordings of clinical interviews in a sample of incarcerated adult men. We observed that higher psychopathy scores were associated with stationary head dwell time. Here, we applied a similar automated algorithm to assess head position and dynamics on videotaped clinical interviews assessing psychopathic traits from n = 242 youth housed at a maximum-security juvenile correctional facility. We observed that higher psychopathy scores (assessed via the Hare Psychopathy Checklist: Youth Version [PCL:YV]) were associated with unique patterns of head dynamics. Specifically, PCL:YV Total, Factor 1 (measuring grandiose-manipulative and callous-unemotional traits), and Facet 1 (measuring grandiose-manipulative traits) scores were associated with a higher proportion of time spent in a head dynamics pattern consisting of moderate movement away from the average head position. This study lays the groundwork for future investigations to apply quantitative methods to better understand patterns of nonverbal communication styles in clinical populations characterized by severe antisocial behavior.

Reduced structural integrity of the uncinate fasciculus in incarcerated women scoring high on psychopathy

Both men and women scoring high on psychopathy exhibit similar structural and functional neural abnormalities, including reduced volume of the orbitofrontal cortex (OFC) and reduced hemodynamic activity in the amygdala during affective processing experimental paradigms. The uncinate fasciculus (UF) is a white matter (WM) tract that connects the amygdala to the OFC. Reduced structural integrity of the UF, measured via fractional anisotropy (FA), is commonly associated with men scoring high on psychopathy. However, only one study to date has investigated the relationship between psychopathic traits and UF structural integrity in women, recruiting participants from a community sample. Here, we investigated whether Hare Psychopathy Checklist-Revised (PCL-R) facet scores (measuring interpersonal, affective, lifestyle/behavioral, and antisocial psychopathic traits, respectively) were associated with reduced FA in the left and right UF in a sample of 254 incarcerated women characterized by a wide range of psychopathy scores. We observed that PCL-R Facet 3 scores, assessing lifestyle/behavioral psychopathic traits, were associated with reduced FA in the left and right UF, even when controlling for participant's age and history of previous substance use. The results obtained in the current study help improve our understanding of structural abnormalities associated with women scoring high on psychopathy. Specifically, reduced UF structural integrity may contribute to some of the deficits commonly associated with women scoring high on psychopathy, including emotion dysregulation.

Individual differences in white matter of the uncinate fasciculus and inferior fronto-occipital fasciculus: possible early biomarkers for callous-unemotional behaviors in young children with disruptive behavior problems

BACKGROUND

Callous-unemotional (CU) behaviors are important for identifying severe patterns of conduct problems (CP). One major fiber tract implicated in the development of CP is the uncinate fasciculus (UF), which connects amygdala and orbitofrontal cortex (OFC). The goals of the current study were to (a) explore differences in the white matter microstructure in the UF and other major fiber tracks between young typically developing (TD) children and those with a disruptive behavior disorder (DBD) and (b) explore, within the DBD group, whether individual differences in these white matter tracts relate to co-occurring CP and CU behaviors.

METHODS

Participants included 198 young children (69% boys, M_age  = 5.66 years; 80% Latinx; 48.5% TD). CU behaviors and CP were measured via a combination of teacher/parent ratings. Non-invasive diffusion-weighted imaging (DWI) was used to measure fractional anisotropy (FA), an indirect indicator of white matter properties.

RESULTS

Relative to TD children, children in the DBD group had reduced FA on four out of the five fiber tracks we examined (except for cingulum and right ILF), even after accounting for whole brain FA, sex, movement, parental income, and IQ. Within the DBD group, no associations were found between CP and reduced white matter integrity across any of the fiber tracks examined. However, we found that even after accounting for CP, ADHD symptomology, and a host of covariates (whole brain FA, sex, movement, parental income, and IQ), CU behaviors were independently related to reduced FA in bilateral UF and left inferior fronto-occipital fasciculus (IFOF) in the DBD group, but this was not the case for TD children.

CONCLUSIONS

Alterations in the white matter microstructure within bilateral UF and left IFOF may be biomarkers of CU behaviors, even in very young children.

Sex matters: association between callous-unemotional traits and uncinate fasciculus microstructure in youths with conduct disorder

Among youths with conduct disorder, those with callous-unemotional traits are at increased risk for persistent antisocial behaviour. Although callous-unemotional traits have been found to be associated with white-matter brain abnormalities, previous diffusion imaging studies were conducted in small samples, preventing examination of potential sex by callous-unemotional traits interaction effects on white matter. Here, we used tract-based spatial statistics at a whole-brain level and within regions of interest to compare the white matter correlates of callous-unemotional traits in female vs. male youths with conduct disorder, in a sample (n = 124) recruited through a multi-site protocol. A sex-specific association between callous-unemotional traits and white matter was found in the left uncinate fasciculus, where callous-unemotional traits were positively associated with axial diffusivity in males, while an opposite pattern was found in females. These findings are in line with previous studies suggesting that the uncinate fasciculus is a key tract implicated in the development of psychopathy, but also add to recent evidence showing that sexual dimorphism needs to be taken into account when examining the structural correlates of mental disorders in general, and callous-unemotional traits in conduct disorder in particular.