Aggression in young children with concurrent callous-unemotional traits: can the neurosciences inform progress and innovation in treatment approaches?

Do Children with High Callous-Unemotional Traits Have Attentional Deficits to Emotional Stimuli? Evidence from a Multi-Method and Multi-Informant Study

Callous-unemotional (CU) traits in children and adolescents are linked to severe and persistent antisocial behavior. Based on past empirical research, several theoretical models have suggested that CU traits may be partly explained by difficulties in correctly identifying others' emotional states as well as their reduced attention to others' eyes, which could be important for both causal theory and treatment. This study tested the relationships among CU traits, emotion recognition of facial expressions and visual behavior in a sample of 52 boys referred to a clinic for conduct problems (Mage = 10.29 years; SD = 2.06). We conducted a multi-method and multi-informant assessment of CU traits through the Child Problematic Traits Inventory (CPTI), the Inventory of Callous-Unemotional (ICU), and the Clinical Assessment of Prosocial Emotions-Version 1.1 (CAPE). The primary goal of the study was to compare the utility of these methods for forming subgroups of youth that differ in their emotional processing abilities. An emotion recognition task assessed recognition accuracy (percentage of mistakes) and absolute dwell time on the eyes or mouth region for each emotion. Results from repeated measures ANOVAs revealed that low and high CU groups did not differ in emotion recognition accuracy, irrespective of the method of assessing CU traits. However, the high CU group showed reduced attention to the eyes of fearful and sad facial expressions (using the CPTI) or to all emotions (using the CAPE). The high CU group also showed a general increase in attention to the mouth area, but only when assessed by the CAPE. These findings provide evidence to support abnormalities in how those elevated on CU traits process emotional stimuli, especially when assessed by a clinical interview, which could guide appropriate assessment and more successful interventions for this group of youth.

The Effects of Psychopathy Facets on Treatment Involvement

The current study explored the relations between patient characteristics and psychopathic traits in predicting treatment involvement. We rated treatment involvement using detailed archival clinical files of 218 individuals committed to the Massachusetts Treatment Center (MTC). Psychopathy Checklist-Revised (PCL-R) scores had been rated from a previous study on the same sample. Overall, PCL-R Facets 2 and 4 significantly predicted decreases in treatment involvement, suggesting the characteristics associated with these facets have the most disruptive effects on treatment involvement. Exploratory analyses were also conducted assessing the relations between the PCL-R facets and the individual treatment involvement components. Whereas Facet 2 significantly predicted lower levels in all three individual treatment involvement components, Facet 4 only significantly predicted lower levels in two, highlighting the differentiating effects of these facets. Identifying the components that have either positive or negative effects on treatment involvement can allow clinicians to tailor treatments to optimize treatment involvement and outcome.

Serotonin 5-HT2A receptor polymorphisms are associated with irritability and aggression in conduct disorder

In childhood and adolescence, overt antisocial and aggressive manifestations are typically diagnosed as conduct disorder (CD). Given that the emerging research has pointed to the influence of 5-HT_2A receptors in the ontogeny of aggression, we aimed to analyze the association of its genetic polymorphisms with CD. The study included 228 male adolescent subjects (120 with and 108 without CD). CD was diagnosed according to Structured Clinical Interview for DSM-IV criteria, while evaluations of aggressive/dissociative behaviors were performed using psychometric questionnaires including the PCL-YV, OAS-M, KADS, and CBCL. Platelet 5-HT concentration was determined by spectrophotofluorometry. Genotyping of 5-HT_2A receptor polymorphisms rs2070040, rs9534511, rs4142900, rs9534512 was performed using TaqMan SNP Genotyping Assays. Subjective irritability, physical aggression toward others, and antisocial behavior were strongly associated with the G allele of rs2070040 and rs4142900, and the C allele of rs9534511 and rs9534512. A significantly increased platelet 5-HT concentration in CD subjects, compared to controls, was lost after the correction according to the smoking status. Our results indicate an association of the studied HTR2A polymorphisms and their haplotypes with irritability and impulsivity traits, which may contribute to the aggressive and antisocial behavior in male adolescents with CD.

Modulation of cognitive flexibility by reward and punishment in BALB/cJ and BALB/cByJ mice

Learning from feedback is one of the key mechanisms within cognitive flexibility, which is needed to react swiftly to constantly changing environments. The motivation to change behavior is highly dependent on the expectancy of positive (reward) or negative (punishment) feedback. Individuals with conduct disorder (CD) with high callous unemotional traits show decreased sensitivity to negative feedback and increased reward seeking. Previous studies have modeled traits associated with CD (i.e. heightened aggression and anti-social behavior) in BALB/cJ mice (compared to the BALB/cByJ mouse as controls). Based on these findings, we hypothesized reduced negative feedback-related cognitive flexibility to be present in BALB/cJ mice. The effect of negative feedback and reward sensitivity on cognitive flexibility in BALB/cJ and BALB/cByJ mice was examined in a reversal learning paradigm. BALB/cJ mice were more flexible in the acquisition of new contingencies under rewarding conditions compared to BALB/cByJ mice, while the presence of an aversive punishing stimulus decreased their learning performance. Additionally, BALB/cJ mice needed more correction trials to reach the reversal learning criterion. This was accompanied by a higher rate of perseverance, which could represent impaired error detection. The addition of a second punishment enhanced punishment sensitivity in BALB/cJ mice. In contrast, the performance of the BALB/cByJ mice was not affected by additional negative feedback. Taken together, the BALB/cJ can be considered to be less sensitive to learn from negative feedback and therefore may be a useful model to further characterize molecular and neural underpinnings of callous unemotional traits in CD.

Amygdala GluN2B-NMDAR dysfunction is critical in abnormal aggression of neurodevelopmental origin induced by St8sia2 deficiency

Aggression is frequently observed in neurodevelopmental psychiatric disorders such as schizophrenia, autism, and bipolar disorder. Due to a lack of understanding of its underlying mechanisms, effective treatments for abnormal aggression are still missing. Recently, genetic variations in Sialyltransferase 2 (St8sia2) have been linked to these disorders and aggression. Here we identify abnormal aggressive behaviors and concomitant blunted fear learning in St8sia2 knockout (-/-) mice. It is worth noting that the amygdala of St8sia2-/- mice shows diminished threat-induced activation, as well as alterations in synaptic structure and function, including impaired GluN2B-containing NMDA receptor-mediated synaptic transmission and plasticity. Pharmacological rescue of NMDA receptor activity in the amygdala of St8sia2-/- mice with the partial agonist D-cycloserine restores synaptic plasticity and normalizes behavioral aberrations. Pathological aggression and associated traits were recapitulated by specific amygdala neonatal St8sia2 silencing. Our results establish a developmental link between St8sia2 deficiency and a pathological aggression syndrome, specify synaptic targets for therapeutic developments, and highlight D-cycloserine as a plausible treatment.

A Pilot Study of Emotional Response to Time-Out in Children With Conduct Problems and Callous-Unemotional Traits

Little research has examined how children with conduct problems and concurrent callous-unemotional traits (CPCU) emotionally and behaviorally respond to time-out. This pilot study examined the distribution and stability of emotions during time-out as well as the association between emotions and negative behaviors. Participants were 11 children (M_age = 9.8 years) with CPCU who participated in a summer treatment program designed specifically for children with CPCU. Summer treatment program counselors rated each child's emotion when time-out was first assigned and then as the time-out progressed and indicated whether the child had negative behavior during time-out. These ratings were completed for approximately 30% of time-outs that occurred. Results showed that children were mostly rated as "unemotional" or "calm" and that these emotions were relatively stable throughout time-out. Furthermore, negative behaviors were most common during time-outs when children's emotions were rated as "amused." Results provide groundwork for future research to extend upon the methods used in the current study to further examine the emotional and behavioral response to time-out in children with CPCU.

Can reciprocated parent-child eye gaze and emotional engagement enhance treatment for children with conduct problems and callous-unemotional traits: a proof-of-concept trial

BACKGROUND

High levels of callous-unemotional (CU) traits are associated with reduced effectiveness of parenting programmes for children with conduct problems. This may be due to low levels of emotional engagement (EE) by these children with their parents. We evaluate a theoretically driven strategy for improving emotional engagement in high CU traits children undergoing a parenting intervention (parent management training; PMT) for child conduct problems.

METHODS

N = 40, 3- to 8-year-old children referred for conduct problems and showing stable, high levels of CU traits, were randomised to receive PMT+Emotional Engagement (EE), or the control condition PMT+Child Centred Play (CCP). A benchmarking sample of N = 70 children who received PMT only was also included. Observational coding of the parent-child interactions targeted by EE and CCP respectively was repeated throughout treatment and follow-up.

RESULTS

Emotional engagement produced unique improvements in parent-child emotional engagement (shared eye gaze); however, these reverted to baseline levels after treatment. CCP produced unique improvements in parents' child centeredness and child positive play, but by post-treatment, all children had improved on these factors. Both interventions produced similar improvements in general parental warmth. Reductions in severity of conduct problems at post-treatment and follow-up were large in size and did not differ between conditions or from the benchmarking group. Levels of CU traits reduced significantly but again did not differ between groups.

CONCLUSIONS

The putative mechanism of emotional engagement through reciprocated eye gaze proved to be impervious to sustained change, and thus failed to have a specific impact of conduct problems or levels of CU traits. The development of novel treatment approaches to children with high levels of CU is a challenging endeavour, and these results indicate that focussing on children with stable levels at pretreatment should be a priority.

Peripubertal stress-induced heightened aggression: modulation of the glucocorticoid receptor in the central amygdala and normalization by mifepristone treatment

Despite the enormous negative impact of excessive aggression for individuals and societies, there is a paucity of treatments. Here, using a peripubertal stress model of heightened aggression in rats, we investigated the involvement of the glucocorticoid system and tested the effectiveness of antiglucocorticoid treatment to normalize behavior. We assessed peripubertal stress-induced changes in glucocorticoid (GR) and mineralocorticoid (MR) gene expression in different amygdala nuclei and hippocampus, and report a specific increase in GR mRNA expression in the central amygdala (CeA). Administration of mifepristone (10 mg/kg), a GR antagonist, before stressor exposure at peripuberty prevented the habituation of plasma corticosterone responses observed throughout the stress protocol. This treatment also prevented the increase in aggression and GR expression in the CeA observed in peripubertally stressed rats at adulthood. Viral downregulation of CeA GR expression at adulthood led to reduced aggression. Subsequently, we showed that a brief, 3-day, treatment with mifepristone at adulthood was effective to normalize the abnormal aggression phenotype in peripubertally stressed rats. Our results support a key role for GR actions during peripubertal stress for the long-term programming of heightened aggression. Strikingly, they also support the translational interest of testing the effectiveness of mifepristone treatment to diminish reactive aggression in early adversity-related human psychopathologies.

The genetic underpinnings of callous-unemotional traits: A systematic research review

BACKGROUND

Callous-unemotional (CU) traits represent the affective features of psychopathy used to delineate youth at high risk for externalizing pathology. The genetic etiology CU traits is not currently well-understood.

METHODS

The current review surveyed the literature for studies on the genetic underpinnings of CU traits and integrated information from 39 genetic studies.

RESULTS

The results from 24 studies with quantitative data suggest that the heritability for CU traits is likely between 36-67%. A majority of the 16 molecular genetic studies focused on candidate genes in the serotonin and oxytocin systems with results that have not been well replicated. Although two genome-wide association studies have been conducted, no genome-wide significant loci have been discovered.

DISCUSSION

There is some evidence to suggest that the serotonin and oxytocin systems may play a role in CU traits; however, there is currently not enough evidence to implicate specific genetic mechanisms. The authors encourage researchers to continue to apply the most up-to-date and relevant methodology, specifically collaborations and consortiums using genome-wide and polygenic methods.

Callous-unemotional traits, low cortisol reactivity and physical aggression in children: findings from the Wirral Child Health and Development Study

Callous-unemotional (CU) traits are thought to confer risk for aggression via reduced amygdala responsivity to distress cues in others. Low cortisol reactivity is thought to confer risk for aggression via reduced arousal and this effect may be confined to boys. We tested the hypothesis that the association between childhood CU traits and aggression would be greatest in the absence of the inhibitory effects of cortisol reactivity, and that this effect would be sex dependent. Participants were 283 members of a stratified subsample within an epidemiological longitudinal cohort (WCHADS). Cortisol reactivity to a social stressor was assessed at 5 years. CU traits were reported by mothers at 5 years, and physical aggression by mothers and teachers at age 7. Results showed that CU traits were associated with elevated aggression at 7 years controlling for earlier aggression. There was no main effect of cortisol reactivity on regression. The association between CU traits and aggression was moderated by cortisol reactivity (p = .011) with a strong association between CU traits and aggression in the presence of low reactivity, and a small and non-significant association in the presence of high reactivity. This association was further moderated by child sex (p = .041) with the joint effect of high CU traits and low cortisol reactivity seen only in boys (p = .016). We report first evidence that a combined deficit in inhibitory processes associated with CU traits and low cortisol reactivity increases risk for childhood aggression, in a sex-dependent manner.

Interactions Between Oxytocin Receptor Gene Methylation and Callous-Unemotional Traits Impact Socioaffective Brain Systems in Conduct-Disordered Offenders

BACKGROUND

The developmental trajectory of psychopathy seemingly begins early in life and includes the presence of callous-unemotional (CU) traits (e.g., perturbed socioaffective reactivity and empathy, callousness) in youths with conduct disorder (CD). Whereas oxytocin receptor gene methylation (OXTR_Meth) and its downstream neuromodulatory effects are deemed relevant to CU traits, nothing is known of how OXTR_Meth interacts with CU traits to impact socioaffective brain systems in youngsters with CD.

METHODS

Hence, we uniquely probed OXTR_Meth × CU trait interactions on corticolimbic activity and amygdala subregional connections during recognition and resonance of distressing socioaffective stimuli (angry and fearful faces), in juvenile offenders with CD (n = 39) versus matched healthy control youths (n = 27).

RESULTS

Relative to healthy control youths, elevated OXTR_Meth and CU levels in youths with CD essentially interacted to predict frontoparietal hyperactivity and amygdalo-frontoparietal disconnection during task performance. Specifically, increasing OXTR_Meth and CU levels in youths with CD interactively predicted midcingulate hyperactivity during both emotion conditions, with insular, temporoparietal, and precuneal hyperactivity additionally emerging during emotion recognition. Interactions between high OXTR_Meth and CU levels in youths with CD additionally predicted centromedial amygdala decoupling from ventromedial/orbitofrontal regions during emotion recognition, along with basolateral amygdala decoupling from precuneal and temporoparietal cortices during emotion resonance.

CONCLUSIONS

These results uniquely suggest that interactions between OXTR_Meth and CU traits in youths with CD may affect brain systems critical to decoding and integrating socioaffective information. Developmental models of CU traits and psychopathy could thus possibly advance by further examining OXTR epigenetic effects, which may hold promise for indicated prevention and personalized treatment by targeting oxytocinergic function.

Social Learning Requires Plasticity Enhanced by Fluoxetine Through Prefrontal Bdnf-TrkB Signaling to Limit Aggression Induced by Post-Weaning Social Isolation

Escalated or abnormal aggression induced by early adverse experiences is a growing issue of social concern and urges the development of effective treatment strategies. Here we report that synergistic interactions between psychosocial and biological factors specifically ameliorate escalated aggression induced by early adverse experiences. Rats reared in isolation from weaning until early adulthood showed abnormal forms of aggression and social deficits that were temporarily ameliorated by re-socialization, but aggression again escalated in a novel environment. We demonstrate that when re-socialization was combined with the antidepressant fluoxetine, which has been shown to reactivate juvenile-like state of plasticity, escalated aggression was greatly attenuated, while neither treatment alone was effective. Early isolation induced a permanent, re-socialization-resistant reduction in Bdnf expression in the amygdala and the infralimbic cortex. Only the combined treatment of fluoxetine and re-socialization was able to recover Bdnf expression via epigenetic regulation. Moreover, the behavior improvement after the combined treatment was dependent on TrkB activity. Combined treatment specifically strengthened the input from the ventral hippocampus to the mPFC, suggesting that this pathway is an important mediator of the beneficial behavioral effects of the combined psychosocial and pharmacological treatment of abnormal aggression. Our findings suggest that synergy between pharmacological induction of plasticity and psychosocial rehabilitation could enhance the efficacy of therapies for pathological aggression.

The Development of Severe and Chronic Violence Among Youth: The Role of Psychopathic Traits and Reward Processing

Psychopathic traits are a manifestation of a personality pathology that comprises a core affective-interpersonal dysfunction (callous-unemotional traits) and an impulsive-antisocial behavioral component. Of particular importance, psychopathic traits are associated with the perpetration of some of the most severe acts of violence, and they appear to indicate a subset of youth at risk for earlier onset, greater frequency, and persistence of violent offending. Although these youth represent a minority of the population, they commit a significant proportion of the violence in the general community. In our review, we highlight evidence of a unique neurobiological predisposition that underlies the core affective deficits and describe contemporary accounts for the developmental processes leading to the antisocial behavior associated with psychopathy. Current evidence suggests that, for this subset of youth, the structure and function of neural circuitry supporting emotion processing, reward learning, decision making, and the development of emotion related to empathy may be crucial to understanding why they are at risk for violence. In particular, a reward dominant pattern of neurobehavioral conditioning may explain how these youth progress to some of the most severe and persistent forms of violence. However, this pattern of conditioning may also be essential to the primary prevention of such deleterious behavior. We suspect that effective strategies to prevent such violence may ultimately be informed by understanding these affective and motivational mechanisms.

Toward an Understanding of the Role of the Environment in the Development of Early Callous Behavior

Key to understanding the long-term impact of social inequalities is identifying early behaviors that may signal higher risk for later poor psychosocial outcomes, such as psychopathology. A set of early-emerging characteristics that may signal risk for later externalizing psychopathology is callous-unemotional (CU) behavior. CU behavior predicts severe and chronic trajectories of externalizing behaviors in youth. However, much research on CU behavior has focused on late childhood and adolescence, with little attention paid to early childhood when preventative interventions may be most effective. In this article, we summarize our recent work showing that (a) CU behavior can be identified in early childhood using items from common behavior checklists, (b) CU behavior predicts worse outcomes across early childhood, (c) CU behavior exhibits a nomological network distinct from other early externalizing behaviors, and (d) malleable environmental factors, particularly parenting, may play a role in the development of early CU behaviors. We discuss the challenges of studying contextual contributors to the development of CU behavior in terms of gene-environment correlations and present initial results from work examining CU behavior in an adoption study in which gene-environment correlations are examined in early childhood. We find that parenting is a predictor of early CU behavior even in a sample in which parents are not genetically related to the children.

Unpacking externalising problems: negative parenting associations for conduct problems and irritability

BACKGROUND

Reciprocal associations between negative parenting and child externalising problems are well documented, but measures commonly include child irritability, masking potential distinct associations for irritability and conduct problems.

AIMS

To illuminate links between negative parenting, child conduct problems and irritability over time.

METHOD

A cross-lagged monozygotic (MZ) twin differences design was used in a UK sample (3154 twin pairs) at 4, 7 and 9 years.

RESULTS

Within-pair MZ differences in negative parenting were found to relate longitudinally to differences in conduct problems and irritability. Of note, negative parenting at age 7 was found to relate particularly to increased irritability at 9 years.

CONCLUSIONS

Once genetics are taken into account, irritability in middle childhood may be particularly vulnerable to negative parenting, suggesting support for its malleability to parent-based intervention.

Bidirectional associations between parental warmth, callous unemotional behavior, and behavior problems in high-risk preschoolers

Research suggests that parental warmth and positive parent-child interactions predict the development of conscience and empathy. Recent studies suggest that affective dimensions of parenting, including parental warmth, are associated with fewer behavior problems among children with high levels of callous-unemotional (CU) behavior. Evidence also suggests that CU behavior confers risk for behavior problems by uniquely shaping parenting. The current study examines reciprocal associations between parental warmth, CU behavior, and behavior problems among toddlers. Data from mother-child dyads (N = 731; 49 % female) were collected from a multi-ethnic, high-risk sample at ages 2 and 3. CU behavior was assessed using a previously validated measure (Hyde et al. 2013). Models were tested using two measures of parental warmth, the first from direct observations of warmth in the home, the second coded from 5-min speech samples. Three-way cross-lagged, simultaneous effects models showed that parental warmth predicted child CU behavior, over and above associations with behavior problems. There were cross-lagged associations between directly observed parental warmth and child CU behavior, suggesting these behaviors show some malleability during toddlerhood and that parenting appears to reflect some adaptation to child behavior. The results have implications for models of early-starting behavior problems and preventative interventions for young children.

Amygdala reactivity and negative emotionality: divergent correlates of antisocial personality and psychopathy traits in a community sample

Previous studies have emphasized that antisocial personality disorder (APD) and psychopathy overlap highly but differ critically in several features, notably negative emotionality (NEM) and possibly amygdala reactivity to social signals of threat and distress. Here we examined whether dimensions of psychopathy and APD correlate differentially with NEM and amygdala reactivity to emotional faces. Testing these relationships among healthy individuals, dimensions of psychopathy and APD were generated by the profile matching technique of Lynam and Widiger (2001), using facet scales of the NEO Personality Inventory-Revised, and amygdala reactivity was measured using a well-established emotional faces task, in a community sample of 103 men and women. Higher psychopathy scores were associated with lower NEM and lower amygdala reactivity, whereas higher APD scores were related to greater NEM and greater amygdala reactivity, but only after overlapping variance in APD and psychopathy was adjusted for in the statistical model. Amygdala reactivity did not mediate the relationship of APD and psychopathy scores to NEM. Supplemental analyses also compared other measures of factors within psychopathy in predicting NEM and amygdala reactivity and found that Factor 2 psychopathy was positively related to NEM and amygdala reactivity across measures of psychopathy. The overall findings replicate seminal observations on NEM in psychopathy by Hicks and Patrick (2006) and extend this work to neuroimaging in a normative population. They also suggest that one critical way in which APD and psychopathy dimensions may differ in their etiology is through their opposing levels of NEM and amygdala reactivity to threat.

Child and adolescent changes to DSM-5

AIM

To describe child and adolescent changes to the DSM-5 and discuss controversial changes.

METHOD

Relevant changes to the structure and categorization of DSM-5 childhood conditions are examined, and controversial issues noted.

RESULTS

Important overlaps between a number of new conditions are described, and questions raised in relation to underlying assumptions about some new categories.

CONCLUSION

Further research is required to determine the validity of new conditions, and the clinical and service effects of structural changes, particularly in respect of overlapping disorders, and categorical vs severity descriptors.

Intervention effects on negative affect of CPS-referred children: results of a randomized clinical trial

Exposure to early adversity places young children at risk for behavioral, physiological, and emotional dysregulation, predisposing them to a range of long-term problematic outcomes. Attachment and Biobehavioral Catch-up (ABC) is a 10-session intervention designed to enhance children's self-regulatory capabilities by helping parents to behave in nurturing, synchronous, and non-frightening ways. The effectiveness of the intervention was assessed in a randomized clinical trial, with parents who had been referred to Child Protective Services (CPS) for allegations of maltreatment. Parent-child dyads received either the ABC intervention or a control intervention. Following the intervention, children from the ABC intervention (n=56) expressed lower levels of negative affect during a challenging task compared to children from the control intervention (n=61).

Parent Training Outcomes among Young Children with Callous-Unemotional Conduct Problems with or At-Risk for Developmental Delay

School-aged children with conduct problems and high levels of callous-unemotional (i.e., lack of empathy, guilt, and lack of caring behaviors) traits (CP+CU) tend to yield less benefit from traditional interventions than do their low-CU counterparts, particularly with respect to CP outcomes. To date, little is known about treatment response among young children with CP+CU, particularly those with or at risk for developmental delay. Components of Parent-Child Interaction Therapy (PCIT), a parent training program effective at reducing CP in young children, have compelling theoretical support for addressing core deficits unique to children with CP+CU and have been used successfully with young children with developmental delay. Our first aim was to test the psychometric properties of a measure of CU traits in preschool children with and without developmental delay. Our second aim was to test whether CU traits predicted post-treatment CP after controlling for initial levels of CP. Participants were 63 families of young children (mean age = 3.87 years), with or at-risk for developmental delay, who presented with elevated CP and were treated in a hospital-based outpatient clinic. Results indicated that developmentally delayed children with high levels of CU traits, but not children at-risk for delay due to premature birth, showed significantly poorer CP outcomes following treatment with PCIT than did children scoring low on CU traits, even after controlling for initial CP severity. The implications of these findings with regard to treating and preventing severe disruptive behaviors among young children with CP+CU are discussed.

Justice policy reform for high-risk juveniles: using science to achieve large-scale crime reduction

After a distinctly punitive era, a period of remarkable reform in juvenile crime regulation has begun. Practical urgency has fueled interest in both crime reduction and research on the prediction and malleability of criminal behavior. In this rapidly changing context, high-risk juveniles--the small proportion of the population where crime becomes concentrated--present a conundrum. Research indicates that these are precisely the individuals to treat intensively to maximize crime reduction, but there are both real and imagined barriers to doing so. Mitigation principles (during early adolescence, ages 10-13) and institutional placement or criminal court processing (during mid-late adolescence, ages 14-18) can prevent these juveniles from receiving interventions that would best protect public safety. In this review, we synthesize relevant research to help resolve this challenge in a manner that is consistent with the law's core principles. In our view, early adolescence offers unique opportunities for risk reduction that could (with modifications) be realized in the juvenile justice system in cooperation with other social institutions.

Dimensions of callousness in early childhood: links to problem behavior and family intervention effectiveness

This study examined dimensions of callous behaviors in early childhood and the role of these behaviors in the development of conduct problems, as well as responsiveness to a family-centered preventative intervention. Caregiver reports of callous behaviors were examined using exploratory and confirmatory factor analysis. Problem behavior was examined using within- and cross-informant reports of these behaviors. Parenting was measured using observational methods within the context of a randomized control trial of the Family Check-Up with a sample of 731 ethnically diverse boys and girls (followed from ages 2 to 4) at high risk for later conduct problems. Results demonstrated that a measure of deceitful-callous (DC) behaviors had acceptable factor loadings and internal consistency at ages 3 and 4. DC behaviors at age 3 predicted problem behavior concurrently and longitudinally within and across informant. However, DC behaviors did not reduce the effectiveness of the family preventative intervention. These findings have implications for our understanding of behaviors that may precede later callous-unemotional traits and for our understanding of the development and prevention of early starting conduct problems.

The cognitive and neural correlates of psychopathy and especially callous–unemotional traits in youths: A systematic review of the evidence

It is unclear whether the concepts and findings of the underlying neurobiology of adult psychopathy apply to youths as well. If so, a life span approach to treatment should be taken. Because youths’ brains are still developing, interventions at an early age may be far more effective in the long run. The aim of this systematic review is to examine whether the neurocognitive and neurobiological factors that underlie juvenile psychopathy, and specifically callous–unemotional (CU) traits, are similar to those underlying adult psychopathy. The results show that youths with CU traits show lower levels of prosocial reasoning, lower emotional responsivity, and decreased harm avoidance. Brain imaging studies in youths with CU traits are still rare. Available studies suggest specific neural correlates, such as a reduced response of the amygdala and a weaker functional connectivity between the amygdala and the ventromedial prefrontal cortex. These findings are largely in line with existing theories of adult psychopathy, such as the dual-hormone serotonergic hypothesis and the integrated emotions systems theory. We recommend that future studies investigate the role of oxytocin, invest in the study of neural mechanisms, and study the precursors, risk factors, and correlates of CU traits in early infancy and in longitudinal designs.

Methylation of the oxytocin receptor gene and oxytocin blood levels in the development of psychopathy

Child conduct problems (CPs) are a robust predictor of adult mental health; the concurrence of callous–unemotional (CU) traits confers specific risk for psychopathy. Psychopathy may be related to disturbances in the oxytocin (OXT) system. Evidence suggests that epigenetic changes in the OXT receptor gene (OXTR) are associated with lower circulating OXT and social–cognitive difficulties. We tested methylation levels of OXTR in 4- to 16-year-old males who met DSM criteria for a diagnosis of oppositional–defiant or conduct disorder and were stratified by CU traits and age. Measures were DNA methylation levels of six CpG sites in the promoter region of the OXTR gene (where a CpG site is a cytosine nucleotide occurs next to a guanine nucleotide in the linear sequence of bases along its lenth, linked together by phosphate binding), and OXT blood levels. High CU traits were associated with greater methylation of the OXTR gene for two cytosine nucleotide and guanine nucleotide phosphate linked sites and lower circulating OXT in older males. Higher methylation correlated with lower OXT levels. We conclude that greater methylation of OXTR characterizes adolescent males with high levels of CU and CPs, and this methylation is associated with lower circulating OXT and functional impairment in interpersonal empathy. The results add genetic evidence that high CU traits specify a distinct subgroup within CP children, and they suggest models of psychopathy may be informed by further identification of these epigenetic processes and their functional significance.

Polymorphisms in the oxytocin receptor gene are associated with the development of psychopathy

The co-occurrence of child conduct problems (CPs) and callous–unemotional (CU) traits confers risk for psychopathy. The oxytocin (OXT) system is a likely candidate for involvement in the development of psychopathy. We tested variations in the OXT receptor gene (OXTR) in CP children and adolescents with varying levels of CU traits. Two samples of Caucasian children, aged 4–16 years, who met DSM criteria for disruptive behavior problems and had no features of autism spectrum disorder, were stratified into low versus high CU traits. Measures were the frequencies of nine candidate OXTR polymorphisms (single nucleotide polymorphisms). In Sample 1, high CU traits were associated with single nucleotide polymorphism rs1042778 in the 3′ untranslated region of OXTR and the CGCT haplotype of rs2268490, rs2254298, rs237889, and rs13316193. The association of rs1042778 was replicated in the second rural sample and held across gender and child versus adolescent age groups. We conclude that polymorphic variation of the OXTR characterizes children with high levels of CU traits and CPs. The results are consistent with a hypothesized role of OXT in the developmental antecedents of psychopathy, particularly the differential amygdala activation model of psychopathic traits, and add genetic evidence that high CU traits specify a distinct subgroup within CP children.

Understanding Youth Antisocial Behavior Using Neuroscience through a Developmental Psychopathology Lens: Review, Integration, and Directions for Research

Youth antisocial behavior (AB) is an important public health concern impacting perpetrators, victims, and society. Functional neuroimaging is becoming a more common and useful modality for understanding neural correlates of youth AB. Although there has been a recent increase in neuroimaging studies of youth AB and corresponding theoretical articles on the neurobiology of AB, there has been little work critically examining the strengths and weaknesses of individual studies and using this knowledge to inform the design of future studies. Additionally, research on neuroimaging and youth AB has not been integrated within the broader framework of developmental psychopathology. Thus, this paper provides an in-depth review of the youth AB functional neuroimaging literature with the following goals: 1. to evaluate how this literature has informed our understanding of youth AB, 2. to evaluate current neuroimaging studies of youth AB from a developmental psychopathology perspective with a focus on integrating research from neuroscience and developmental psychopathology, as well as placing this research in the context of other related areas (e.g., psychopathy, molecular genetics), and 3. to examine strengths and weaknesses of neuroimaging and behavioral studies of youth AB to suggest how future studies can develop a more informed and integrated understanding of youth AB.

Antisocial and callous behaviour in children

Antisocial behaviour is one of the most common reasons for a childhood referral to mental health and educational services and represents a substantial public health cost. Callous-unemotional traits can be used to distinguish children who are capable of pre-meditated antisocial behaviour and violence from those whose antisocial behaviour and violence are primarily impulsive and threat reactive. Decades of developmental psychopathology research have shown that children with antisocial behaviour are thus a heterogeneous group and, for interventions to be successful, it is critical that distinct subgroups of children receive services that best match their profile of vulnerabilities and strengths. Recent advances in genetic and brain imaging research in the field have made important contributions to our understanding of the developmental vulnerability that callous-unemotional traits represent. In this chapter, we provide an overview of the current evidence base with regard to genetic and neuroscience findings of callous-unemotional traits and antisocial behaviour with callous-unemotional traits. We also discuss the implications of these findings for prevention and intervention, and finish by outlining what we consider are necessary directions for future research.

Classification issues and challenges in child and adolescent psychopathology

The major advances that have taken place over the last half century are reviewed with a focus on those that are particularly important with respect to classification issues in the field of child and adolescent psychopathology. Attention is paid to the conceptual issues in DSM and ICD development and differences between the two classifications. Specific recommendations for changes in ICD-11 are presented and an online supplement provides specific details with respect to diagnostic categories that are in need of further testing.

Genetic and neurocognitive contributions to the development of psychopathy

An overview is provided of recent twin, molecular genetic, and magnetic resonance imaging studies that are helping to inform a model of developmental vulnerability to adult psychopathy. Although the current evidence base suggests that children with high levels of callous–unemotional traits are genetically and neurocognitively vulnerable to developing psychopathic and antisocial behaviors, existing research also clearly indicates that environmental influences play an important role. One potential implication is that interventions for children with antisocial behavior and callous–unemotional traits may need to be tailored to take into account their distinct pattern of neurocognitive vulnerability, as revealed by developmental neuroimaging studies. Specifically, interventions that pursue punishment-oriented or explicit empathy induction strategies may be less effective with this group of antisocial children. By contrast, preliminary evidence suggests that enhancing positive parenting and parental involvement, as well as applying consistent rewards may represent more promising intervention approaches.

Do callous-unemotional traits moderate the relative importance of parental coercion versus warmth in child conduct problems? An observational study

BACKGROUND

Research suggests that parenting has little influence on the development of antisocial behavior in children with callous-unemotional (CU) traits. We aimed to extend and improve on prior studies examining the moderating role of CU traits on associations between parenting and conduct problems, by using independent observations of two key dimensions of parenting: coercion and warmth.

METHODS

The participants included clinic-referred conduct-disordered boys (4-12 years; N = 95) and their families. Coercive parenting was coded from observations of family interaction and parental warmth was coded from Five-Minute Speech Samples. CU traits and conduct problems were rated by multiple informants.

RESULTS

In both mothers and fathers, CU traits moderated links between observed parenting and conduct problems. Specifically, coercive parenting was more strongly positively associated with conduct problems in boys with lower levels of CU traits, whereas parental warmth was more strongly negatively associated with conduct problems in boys with higher levels of CU traits.

CONCLUSIONS

These findings suggest that different dimensions of parenting may need to be targeted in the treatment of early onset conduct problems in children high and low on CU traits.

Treatment response in CP/ADHD children with callous/unemotional traits

The current study examines the role of callous/unemotional (CU) traits in response to treatment among children with conduct problems (CP) and attention-deficit/hyperactivity disorder (ADHD). Fifty-four children with CP/ADHD and 16 controls (age = 9.48, SD = 1.58) took part in a summer treatment and research program. Simple correlations showed that CU and CP were associated with a number of treatment outcome measures. When examined together in regression analyses, CU and CP were uniquely associated with three treatment outcomes each (CU-improvement in social skills and problem solving, negative behaviors in time-out; CP-time-outs per day, peer ratings, peer dislike). The implications for these findings with regard to treatment response in children with CP/ADHD with and without CU traits are explored.

Support for religio-political aggression among teenaged boys in Gaza: part II: neuroendocrinological findings

Hormones seem to play important roles in the regulation of human aggression. Multiple studies have confirmed that testosterone (T) levels exhibit complex relationships with aggression, dominance, and/or risk-taking behavior. Some evidence suggests that cortisol (CORT) interacts with T and may also be associated with aspects of mood and aggression. However, almost no research to date has investigated the possibility that these neuroendocrine factors are associated with variations in political attitudes or with political aggression. During the second intifada, we tested the hypothesis that morning salivary T and/or salivary CORT levels might be associated with self-rated aggression or with support for religio-political aggression (RPA) among 14-year-old Palestinian boys living in Gaza. We obtained and averaged weekly 09:00 hr salivary measures of T and CORT for more than 1 month. Averaged morning T levels did not correlate with self-rated aggression, but were positively associated with agreement with the statement "religious ends justify any means," (r = .355, P = .014) and marginally associated with a composite measure of support for RPA (r = .247, P = .094). Average CORT levels were inversely correlated with self-rated aggression (r = -.328, P = .037) and with anger (r = -.373, P = .016), but CORT levels were not associated with support for RPA or with the statement "religious ends justify any means." Acknowledging that a modest sample size and methodological issues necessarily limit confidence in our conclusions, these results may represent the first findings regarding neurobiological correlates of support for political aggression.

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

BACKGROUND

This review analyses and summarises the recent advances in understanding the neurobiology of violence and empathy, taxonomical issues on defining personality disorders characterised by disregard for social norms, evidence for efficacy of different treatment modalities and ethical implications in defining 'at-risk' individuals for preventive interventions.

METHODS

PubMed was searched with the keywords 'antisocial personality disorder', 'dissocial personality disorder' and 'psychopathy'. The search was limited to articles published in English over the last 10 years (1999 to 2009)

RESULTS

Both diagnostic manuals used in modern psychiatry, the Diagnostic and Statistical Manual published by the American Psychiatric Association and the International Classification of Diseases published by the World Health Organization, identify a personality disorder sharing similar traits. It is termed antisocial personality disorder in the diagnostic and statistical manual and dissocial personality disorder in the International Classification of Diseases. However, some authors query the ability of the existing manuals to identify a special category termed 'psychopathy', which in their opinion deserves special attention. On treatment-related issues, many psychological and behavioural therapies have shown success rates ranging from 25% to 62% in different cohorts. Multisystemic therapy and cognitive behaviour therapy have been proven efficacious in many trials. There is no substantial evidence for the efficacy of pharmacological therapy. Currently, the emphasis is on early identification and prevention of antisocial behaviour despite the ethical implications of defining at-risk children.

CONCLUSIONS

Further research is needed in the areas of neuroendocrinological associations of violent behaviour, taxonomic existence of psychopathy and efficacy of treatment modalities.

Understanding relations among early family environment, cortisol response, and child aggression via a prevention experiment

This study examined relations among family environment, cortisol response, and behavior in the context of a randomized controlled trial with 92 children (M = 48 months) at risk for antisocial behavior. Previously, researchers reported an intervention effect on cortisol response in anticipation of a social challenge. The current study examined whether changes in cortisol response were related to later child aggression. Among lower warmth families, the intervention effect on aggression was largely mediated by the intervention effect on cortisol response. Although the intervention also resulted in significant benefits on child engaging behavior, cortisol response did not mediate this effect. These findings demonstrate meaningful associations between cortisol response and aggression among children at familial risk for antisocial behavior.

Callous-unemotional traits are related to combined deficits in recognizing afraid faces and body poses

OBJECTIVE

The aim of the present study was to examine accuracy in labeling body poses conveying fear. Youths with callous-unemotional traits experience emotional processing deficits seemingly on par with deficits showed by patients with amygdala damage. That is, there is growing evidence that children with callous-unemotional traits have problems recognizing afraid emotional expressions. Although people with amygdala damage show deficits in labeling afraid faces, they have an intact ability to label afraid body poses.

METHOD

Boys (N = 55; ages 8-16 years) from a community center were recruited to label emotional faces and static body poses and to complete the Inventory of Callous-Unemotional Traits and a measure of violence and antisocial behavior.

RESULTS

Callous-unemotional traits were related to poorer accuracy when labeling afraid faces and afraid body postures. However, when response bias was taken into account, callous-unemotional traits were related to deficits in many facial expressions. Notably, the combination of poorly labeling afraid faces and body poses was linked to the highest levels of callous-unemotional traits and violence.

CONCLUSIONS

Findings support a generalized deficit in processing displays of fear that are not specific to faces. The results support the argument that a general "fear-blindness" is related to a lack of empathy and to violence and antisocial behavior. Methodological issues with regard to deciding whether people are accurately labeling fear and other emotions are discussed. However, early identification of fear deficits that affect multiple modalities is argued to be important for clinical intervention.