Differences between psychopathy and other personality disorders: evidence from neuroimaging

A neurocognitive model of early onset persistent and desistant antisocial behavior in early adulthood

It remains unclear which functional and neurobiological mechanisms are associated with persistent and desistant antisocial behavior in early adulthood. We reviewed the empirical literature and propose a neurocognitive social information processing model for early onset persistent and desistant antisocial behavior in early adulthood, focusing on how young adults evaluate, act upon, monitor, and learn about their goals and self traits. Based on the reviewed literature, we propose that persistent antisocial behavior is characterized by domain-general impairments in self-relevant and goal-related information processing, regulation, and learning, which is accompanied by altered activity in fronto-limbic brain areas. We propose that desistant antisocial development is associated with more effortful information processing, regulation and learning, that possibly balances self-relevant goals and specific situational characteristics. The proposed framework advances insights by considering individual differences such as psychopathic personality traits, and specific emotional characteristics (e.g., valence of social cues), to further illuminate functional and neural mechanisms underlying heterogenous developmental pathways. Finally, we address important open questions and offer suggestions for future research to improve scientific knowledge on general and context-specific expression and development of antisocial behavior in early adulthood.

Psychopathic and autistic traits differentially influence the neural mechanisms of social cognition from communication signals

Psychopathy is associated with severe deviations in social behavior and cognition. While previous research described such cognitive and neural alterations in the processing of rather specific social information from human expressions, some open questions remain concerning central and differential neurocognitive deficits underlying psychopathic behavior. Here we investigated three rather unexplored factors to explain these deficits, first, by assessing psychopathy subtypes in social cognition, second, by investigating the discrimination of social communication sounds (speech, non-speech) from other non-social sounds, and third, by determining the neural overlap in social cognition impairments with autistic traits, given potential common deficits in the processing of communicative voice signals. The study was exploratory with a focus on how psychopathic and autistic traits differentially influence the function of social cognitive and affective brain networks in response to social voice stimuli. We used a parametric data analysis approach from a sample of 113 participants (47 male, 66 female) with ages ranging between 18 and 40 years (mean 25.59, SD 4.79). Our data revealed four important findings. First, we found a phenotypical overlap between secondary but not primary psychopathy with autistic traits. Second, primary psychopathy showed various neural deficits in neural voice processing nodes (speech, non-speech voices) and in brain systems for social cognition (mirroring, mentalizing, empathy, emotional contagion). Primary psychopathy also showed deficits in the basal ganglia (BG) system that seems specific to the social decoding of communicative voice signals. Third, neural deviations in secondary psychopathy were restricted to social mirroring and mentalizing impairments, but with additional and so far undescribed deficits at the level of auditory sensory processing, potentially concerning deficits in ventral auditory stream mechanisms (auditory object identification). Fourth, high autistic traits also revealed neural deviations in sensory cortices, but rather in the dorsal auditory processing streams (communicative context encoding). Taken together, social cognition of voice signals shows considerable deviations in psychopathy, with differential and newly described deficits in the BG system in primary psychopathy and at the neural level of sensory processing in secondary psychopathy. These deficits seem especially triggered during the social cognition from vocal communication signals.

Reading and reacting to faces, the effect of facial mimicry in improving facial emotion recognition in individuals with antisocial behavior and psychopathic traits

Individuals with antisocial behavior and psychopathic traits are characterized by deficits in processing facial expressions, which results in poor social adaptation and dysfunctional interpersonal relationships. However, it is not clear how individuals with varying levels of these traits differ in this emotional impairment and if these deficits are due to correctly identifying or reacting appropriately to facial expressions. The aim of the study was to examine how individuals with these traits recognized and responded to affective facial expressions by using FaceReader software (which analyses footage of faces) across different experimental conditions (imitation, suppression, and control). Imitating facial expressions was introduced to examine whether it could direct participants’ attention to the facial cues and improve participants’ performance on the facial task. A total of 643 individuals from the community were pre-screened and a sample (N = 107; M age = 21.08, SD = 1.55), differentiated on levels of antisocial personality disorder (APD) symptoms and psychopathic (PSY) traits, who were selected based on extreme scores (high/low), were invited to participate in the study. Individuals with higher levels of APD symptoms and PSY traits (APD + PSY) expressed more anger than other groups, while those in the APD-only group expressed more sadness, compared to other groups. Overall, participants were compliant in following the instructions to imitate facial expressions. However, only the group with predominantly APD symptoms and the group with combined symptoms (APD + PSY) showed improvement in their accuracy ratings specifically when instructed to imitate facial expressions, compared to when no instructions were provided. The study offers a promising direction for targeting deficits in facial emotion recognition, suggesting that the deficits found in individuals with behavioral problems (with and without psychopathic traits) can be improved by asking them to imitate facial expressions.

Psychopathy and trauma: Exploring a potential association

This research presents a series of linked studies exploring the association between psychopathy and trauma. It comprises a systematic review (n = 58), followed by an expert Delphi (n = 19), and patient file trawl using a male forensic psychiatric patient sample (n = 66). An association between psychopathy and developmental trauma was predicted. It was further predicted that different types of trauma would be associated with different subtypes of psychopathy and that the severity of trauma would be important. The systematic review identified the following core themes: presence of Post-Traumatic Stress Disorder and/or symptoms; trauma type; trauma/abuse variables; and sex differences. The ensuing Delphi study indicated the specific variant of psychopathy to be important, with secondary psychopathy particularly relevant. The final study found that the severity of developmental trauma related differentially to primary and secondary psychopathy. Implications and directions for future research are discussed, most notably with regards to the conceptualisation of psychopathy.

Cognitive-Emotional and Inhibitory Deficits as a Window to Moral Decision-Making Difficulties Related to Exposure to Violence

In the present review, we illustrate how exposure to violence results in an increased probability of developing functional impairments of decision mechanisms necessary for moral behavior. We focus in particular on the detrimental effects of exposure to violence on emotional (e.g., Empathy), cognitive (e.g., Theory of Mind), and inhibitory control abilities. Relying on studies that document impaired moral behavior in individuals with deficits in these abilities, we propose a "model" of how exposure to violence can affect moral behavior. We then discuss how impaired moral decision making can also be a factor increasing the likelihood of reiterating violence: agents who lack abilities such as understanding and resonating with others' emotions or inhibitory control, can lead to an increase of violent displays. Thus, if not properly addressed, the noxious effects of exposure to violence on morality can lead to a violence generating cycle. We conclude proposing that interventions targeted at improving moral behavior can maximize their efficacy focusing on mitigating the impact of violence on the basic cognitive, emotional, and inhibitory abilities discussed.

Reduced White Matter Integrity in Antisocial Personality Disorder: A Diffusion Tensor Imaging Study

Emerging neuroimaging research suggests that antisocial personality disorder (ASPD) may be linked to abnormal brain anatomy, but little is known about possible impairments of white matter microstructure in ASPD, as well as their relationship with impulsivity or risky behaviors. In this study, we systematically investigated white matter abnormalities of ASPD using diffusion tensor imaging (DTI) measures: fractional anisotropy (FA), axial diffusivity (AD), and radial diffusivity (RD). Then, we further investigated their correlations with the scores of impulsivity or risky behaviors. ASPD patients showed decreased FA in multiple major white matter fiber bundles, which connect the fronto-parietal control network and the fronto-temporal network. We also found AD/RD deficits in some additional white matter tracts that were not detected by FA. More interestingly, several regions were found correlated with impulsivity or risky behaviors in AD and RD values, although not in FA values, including the splenium of corpus callosum, left posterior corona radiate/posterior thalamic radiate, right superior longitudinal fasciculus, and left inferior longitudinal fasciculus. These regions can be the potential biomarkers, which would be of great interest in further understanding the pathomechanism of ASPD.

Are Male Perpetrators of Intimate Partner Violence Different From Convicted Violent Offenders? Examination of Psychopathic Traits and Life Success in Males From a Community Survey

We used data from the Cambridge Study in Delinquent Development, a prospective longitudinal survey of more than 400 males in the United Kingdom followed from age 8 to age 48 to investigate intimate partner violence (IPV) and its association with psychopathy. We investigated the differences in psychopathy scores between those men who were convicted of violence, those who were involved in both extra- and intra-familial violence, and those who committed IPV only. We also considered whether these generally violent men had poorer life success overall with regard to their drinking and drug taking, depression, and other mental disorders. Our findings suggest that those men who are violent both within and outside the home (the generally violent men) are distinguished from those who commit violent crimes outside the home and those who are involved in IPV within the home only. The differences appear to be more in degree than in kind. These findings are discussed with a focus on whether specific interventions are required for those who commit IPV or whether early intervention should be focused on violent behavior in general.

Frontotemporal white-matter microstructural abnormalities in adolescents with conduct disorder: a diffusion tensor imaging study

BACKGROUND

Children with conduct disorder (CD) are at increased risk of developing antisocial personality disorder (ASPD) and psychopathy in adulthood. The biological basis for this is poorly understood. A preliminary diffusion tensor magnetic resonance imaging (DT-MRI) study of psychopathic antisocial adults reported significant differences from controls in the fractional anisotropy (FA) of the uncinate fasciculus (UF), a white-matter tract that connects the amygdala to the frontal lobe. However, it is unknown whether developmental abnormalities are present in the UF of younger individuals with CD.

METHOD

We used DT-MRI tractography to investigate, for the first time, the microstructural integrity of the UF in adolescents with CD, and age-related differences in this tract. We compared FA and perpendicular diffusivity of the UF in 27 adolescents with CD and 16 healthy controls (12 to 19 years old) who did not differ significantly in age, IQ or substance use history. To confirm that these findings were specific to the UF, the same measurements were extracted from two non-limbic control tracts. Participants in the CD group had a history of serious aggressive and violent behaviour, including robbery, burglary, grievous bodily harm and sexual assault.

RESULTS

Individuals with CD had a significantly increased FA (p = 0.006), and reduced perpendicular diffusivity (p = 0.002), in the left UF. Furthermore, there were significant age-related between-group differences in perpendicular diffusivity of the same tract (Z obs = 2.40, p = 0.01). Controls, but not those with CD, showed significant age-related maturation. There were no significant between-group differences in any measure within the control tracts.

CONCLUSIONS

Adolescents with CD have significant differences in the 'connectivity' and maturation of UF.

White matter microstructural abnormalities in the frontal lobe of adults with antisocial personality disorder

Antisocial personality disorder (ASPD) and psychopathy involve significant interpersonal and behavioural impairments. However, little is known about their underlying neurobiology and in particular, abnormalities in white matter (WM) microstructure. A preliminary diffusion tensor magnetic resonance imaging (DT-MRI) study of adult psychopaths employing tractography revealed abnormalities in the right uncinate fasciculus (UF) (Craig et al., 2009), indicating fronto-limbic disconnectivity. However, it is not clear whether WM abnormalities are restricted to this tract or are or more widespread, including other tracts which are involved in connectivity with the frontal lobe. We performed whole brain voxel-based analyses on WM fractional anisotropy (FA) and mean diffusivity (MD) maps acquired with DT-MRI to compare 15 adults with ASPD and healthy age, handedness and IQ-matched controls. Also, within ASPD subjects we related differences in FA and MD to measures of psychopathy. Significant WM FA reduction and MD increases were found respectively in ASPD subjects relative to controls. FA was bilaterally reduced in the genu of corpus callosum while in the right frontal lobe FA reduction was found in the UF, inferior fronto-occipital fasciculus (IFOF), anterior corona radiata and anterior limb and genu of the internal capsule. These differences negatively correlated with measures of psychopathy. Also in the right frontal lobe, increased MD was found in the IFOF and UF, and the corpus callosum and anterior corona radiata. There was a significant positive correlation between MD and psychopathy scores.

CONCLUSIONS

The present study confirms a previous report of reduced FA in the UF. Additionally, we report for the first time, FA deficits in tracts involved in interhemispheric as well as frontal lobe connectivity in conjunction with MD increases in the frontal lobe. Hence, we provide evidence of significant WM microstructural abnormalities in frontal brain regions in ASPD and psychopathy.