The 'antisocial' person: an insight in to biology, classification and current evidence on treatment

A competitively designed version of the point subtraction aggression paradigm is related to proactive aggressive and psychopathic traits in males

The Point Subtraction Aggression Paradigm (PSAP) is a well-validated and frequently applied behavioral paradigm for provocation and quantification of reactive aggressive behavior in laboratory settings. Here, we design and test a newly developed PSAP version in its ability to quantify proactive aggressive behavior. A group of 119 male volunteers was allocated to the conventional PSAP and two other variants of the PSAP. The first PSAP adaptation intended to abet proactive aggression by monetary reward for aggressive actions. In the second variant, a highly competitive situation was created. In addition, two sets of aggression questionnaires, related to proactive and reactive aggressive and psychopathic traits, were used (Reactive-Proactive Aggression Questionnaire (RPQ), Psychopathic Personality Inventory-Revised (PPI-R)). Our results showed strong positive correlations among RPQ/PPI-R and aggressive behavior only for the new competitive version of the PSAP. In contrast, the scores of these scales showed weak and non-significant correlations with observed aggression in the two PSAP variants. The scores for reactive aggression were not significantly associated with any of the PSAP versions. These data indicate that aggression on the newly developed competitive PSAP design is mainly driven by proactive aggressive mechanisms.

Genome-wide association study of antisocial personality disorder

The pathophysiology of antisocial personality disorder (ASPD) remains unclear. Although the most consistent biological finding is reduced grey matter volume in the frontal cortex, about 50% of the total liability to developing ASPD has been attributed to genetic factors. The contributing genes remain largely unknown. Therefore, we sought to study the genetic background of ASPD. We conducted a genome-wide association study (GWAS) and a replication analysis of Finnish criminal offenders fulfilling DSM-IV criteria for ASPD (N=370, N=5850 for controls, GWAS; N=173, N=3766 for controls and replication sample). The GWAS resulted in suggestive associations of two clusters of single-nucleotide polymorphisms at 6p21.2 and at 6p21.32 at the human leukocyte antigen (HLA) region. Imputation of HLA alleles revealed an independent association with DRB1*01:01 (odds ratio (OR)=2.19 (1.53-3.14), P=1.9 × 10(-5)). Two polymorphisms at 6p21.2 LINC00951-LRFN2 gene region were replicated in a separate data set, and rs4714329 reached genome-wide significance (OR=1.59 (1.37-1.85), P=1.6 × 10(-9)) in the meta-analysis. The risk allele also associated with antisocial features in the general population conditioned for severe problems in childhood family (β=0.68, P=0.012). Functional analysis in brain tissue in open access GTEx and Braineac databases revealed eQTL associations of rs4714329 with LINC00951 and LRFN2 in cerebellum. In humans, LINC00951 and LRFN2 are both expressed in the brain, especially in the frontal cortex, which is intriguing considering the role of the frontal cortex in behavior and the neuroanatomical findings of reduced gray matter volume in ASPD. To our knowledge, this is the first study showing genome-wide significant and replicable findings on genetic variants associated with any personality disorder.

Public health system and psychiatry in the treatment of 'dangerous' young offenders in Brazil

We describe the Experimental Health Unit, a special forensic mental health facility in Brazil, created by court order and administered by the São Paulo Department of Health. It was designed for young offenders receiving compulsory inpatient treatment for severe personality disorders. All nine patients admitted to date came from Foundation CASA (a socio-educational centre of assistance for adolescents, the juvenile correctional centres managed by the São Paulo state Department of Justice). The court decision is questionable, relying on a new interpretation of the Child and Adolescent Statute and the law that regulates psychiatric treatment in Brazil. The public health system and psychiatry have been supporting the isolation of some individuals from society, based on the seriousness of their crimes and possession of particular personality characteristics. The decision to commit and send a small group of personality disordered individuals to this unit as inpatients is an unfair decision, since jails and correctional centres hold a high number of psychopathic who have also committed barbaric crimes. The central mental health issue is the role that the public health system should play in the custody of dangerous people; the cost-effectiveness of this model, the accuracy of risk assessment and tractability of people with severe personality disorders are also debatable. From a legal perspective, the operation of this facility raises questions about age of legal majority, the maximum period of incarceration of young offenders and use of whole-life sentences for certain types of crimes and criminals in Brazil.

The impact of dopamine on aggression: an [18F]-FDOPA PET Study in healthy males

Cerebral dopamine (DA) transmission is thought to be an important modulator for the development and occurrence of aggressive behavior. However, the link between aggression and DA transmission in humans has not been investigated using molecular imaging and standardized behavioral tasks. We investigated aggression as a function of DA transmission in a group of (N = 21) healthy male volunteers undergoing 6-[18F]-fluoro-L-DOPA (FDOPA)-positron emission tomography (PET) and a modified version of the Point Subtraction Aggression Paradigm (PSAP). This task measures aggressive behavior during a monetary reward-related paradigm, where a putative adversary habitually tries to cheat. The participant can react in three ways (i.e., money substraction of the putative opponent [aggressive punishment], pressing a defense button, or continuing his money-making behavior). FDOPA-PET was analyzed using a steady-state model yielding estimates of the DA-synthesis capacity (K), the turnover of tracer DA formed in living brain (kloss), and the tracer distribution volume (Vd), which is an index of DA storage capacity. Significant negative correlations between PSAP aggressive responses and the DA-synthesis capacity were present in several regions, most prominently in the midbrain (r = -0.640; p = 0.002). Lower degrees of aggressive responses were associated with higher DA storage capacity in the striatum and midbrain. Additionally, there was a significant positive correlation between the investment into monetary incentive responses on the PSAP and DA-synthesis capacity, notably in the midbrain (r = +0.618, p = 0.003). The results suggest that individuals with low DA transmission capacity are more vulnerable to reactive/impulsive aggression in response to provocation.

Exploring the effects of antisocial personality traits on brain potentials during face processing

Antisocial individuals are characterized to display self-determined and inconsiderate behavior during social interaction. Furthermore, recognition deficits regarding fearful facial expressions have been observed in antisocial populations. These observations give rise to the question whether or not antisocial behavioral tendencies are associated with deficits in basic processing of social cues. The present study investigated early visual stimulus processing of social stimuli in a group of healthy female individuals with antisocial behavioral tendencies compared to individuals without these tendencies while measuring event-related potentials (P1, N170). To this end, happy and angry faces served as feedback stimuli which were embedded in a gambling task. Results showed processing differences as early as 88–120 ms after feedback onset. Participants low on antisocial traits displayed larger P1 amplitudes than participants high on antisocial traits. No group differences emerged for N170 amplitudes. Attention allocation processes, individual arousal levels as well as face processing are discussed as possible causes of the observed group differences in P1 amplitudes. In summary, the current data suggest that sensory processing of facial stimuli is functionally intact but less ready to respond in healthy individuals with antisocial tendencies.

The relationship between personality disorders and Axis I psychopathology: deconstructing comorbidity

The purpose of this review is (a) to study and systematically review the recent literature examining the co-occurrence and relationships between Axis I psychiatric disorders and Axis II personality disorders, specifically the six originally proposed for the Diagnostic and Statistical Manual of Mental Disorders (DSM)-5, and (b) to consider the clinical utility of the current Axis I and Axis II approach in the DSM-IV-TR and apply findings to state a position on the issue of collapsing together Axis I and Axis II. Community surveys or prospective cohort studies were reviewed as a priority. Our review indicates that the associations between clinical disorders and personality disorders clearly varied within each disorder and across the six personality disorders. Our understanding has advanced, particularly related to the clinical utility of comorbidity, and there may be sufficient evidence to support moving borderline personality disorder to Axis I. However, it seems premature to conclude that comorbidity is best conceptualized by having all disorders in a single category or by deleting disorders so that comorbidity is reduced. Our review suggests some priorities for future research into comorbidity, such as including personality disorders in future multivariate comorbidity models.

The ethics of a genetic screening study for antisocial personality disorder with Mesoamericans: case study in the ethics of mental health research

This article contains an analysis of a research ethics committee's (REC) concerns about a study protocol involving genetic screening for antisocial personality disorder. The study was proposed by US university researchers and to be conducted with Mesoamerican populations in the United States and in their countries of origin. The analysis explains why the study was not considered ethical by the REC, pointing to issues with the choice of study population, informed consent, confidentiality, and posttrial obligations. Some recommendations are provided for ways in which the study could have been redesigned.

All about the Money - External Performance Monitoring is Affected by Monetary, but Not by Socially Conveyed Feedback Cues in More Antisocial Individuals

This study investigated the relationship between feedback processing and antisocial personality traits measured by the PSSI questionnaire (Kuhl and Kazén, 1997) in a healthy undergraduate sample. While event-related potentials [feedback related negativity (FRN), P300] were recorded, participants encountered expected and unexpected feedback during a gambling task. As recent findings suggest learning problems and deficiencies during feedback processing in clinical populations of antisocial individuals, we performed two experiments with different healthy participants in which feedback about monetary gains or losses consisted either of social-emotional (facial emotion displays) or non-social cues (numerical stimuli). Since the FRN and P300 are both sensitive to different aspects of feedback processing we hypothesized that they might help to differentiate between individuals scoring high and low on an antisocial trait measure. In line with previous evidence FRN amplitudes were enhanced after negative and after unexpected feedback stimuli. Crucially, participants scoring high on antisocial traits displayed larger FRN amplitudes than those scoring low only in response to expected and unexpected negative numerical feedback, but not in response to social-emotional feedback - irrespective of expectancy. P300 amplitudes were not modulated by antisocial traits at all, but by subjective reward probabilities. The present findings indicate that individuals scoring high on antisociality attribute higher motivational salience to monetary compared to emotional-social feedback which is reflected in FRN amplitude enhancement. Contrary to recent findings, however, no processing deficiencies concerning social-emotional feedback stimuli were apparent in those individuals. This indicates that stimulus salience is an important aspect in learning and feedback processes in individuals with antisocial traits which has potential implications for therapeutic interventions in clinical populations.