Amy L. Byrd

MAOA, childhood maltreatment, and antisocial behavior: meta-analysis of a gene-environment interaction

BACKGROUND In a seminal study of gene-environment interaction, childhood maltreatment predicted antisocial behavior more strongly in male subjects carrying an MAOA promoter variant of lesser, compared with higher, transcriptional efficiency. Many further investigations have been reported, including studies of other early environmental exposures and female subjects. Here, we report a meta-analysis of studies testing the interaction of MAOA genotype and childhood adversities on antisocial outcomes in predominantly nonclinical samples. METHODS Included were 27 peer-reviewed, English-language studies published through August, 2012, that contained indicators of maltreatment or other family (e.g., parenting, sociodemographic) hardships; MAOA genotype; indices of aggressive and antisocial behavior; and statistical test of genotype-environment interaction. Studies of forensic and exclusively clinical samples, clinical cohorts lacking proportionally matched control subjects, or outcomes nonspecific for antisocial behavior were excluded. The Liptak-Stouffer weighted Z-test for meta-analysis was implemented to maximize study inclusion and calculated separately for male and female cohorts. RESULTS Across 20 male cohorts, early adversity presaged antisocial outcomes more strongly for low-activity, relative to high- activity, MAOA genotype (p = .0044). Stratified analyses showed the interaction specific to maltreatment (p = .00000082) and robust to several sensitivity analyses. Across 11 female cohorts, MAOA did not interact with combined early life adversities, whereas maltreatment alone predicted antisocial behaviors preferentially, but weakly, in female subjects of high-activity MAOA genotype (p = .02). CONCLUSIONS We found common regulatory variation in MAOA to moderate effects of childhood maltreatment on male antisocial behaviors, confirming a sentinel finding in research on gene-environment interaction. An analogous, but less consistent, finding in female subjects warrants further investigation.

Understanding desisting and persisting forms of delinquency: the unique contributions of disruptive behavior disorders and interpersonal callousness

BACKGROUND   While associations between conduct disorder (CD), oppositional defiant disorder (ODD), attention deficit hyperactivity disorder (ADHD), and interpersonal callousness (IC) symptoms and delinquency onset are well established, less is known about whether these characteristics differentiate desisting and persisting delinquency. The current study examined whether childhood and adolescent CD, ODD, ADHD, and IC symptoms uniquely distinguished boys who exhibited persisting versus desisting delinquency from adolescence into adulthood. METHODS   Participants were 503 boys (57% African American) repeatedly assessed from ages 7 to 25. Associations between childhood and adolescent CD, ODD, ADHD, and IC symptoms and desisting and persisting delinquency were examined independently and after controlling for their co-occurrence and multiple covariates. RESULTS   Conduct disorder and IC symptoms in childhood and adolescence were higher among boys whose delinquency persisted into adulthood relative to those boys whose delinquency desisted across time. After controlling for the overlap between symptoms of ADHD, ODD, CD and IC, only adolescent CD and IC symptoms emerged as unique predictors of the differentiation between persisters and desisters. Moreover, adolescent CD and IC symptoms continued to contribute unique variance even after childhood levels of these characteristics were accounted for. CONCLUSIONS   Boys with elevated levels of CD and IC symptoms in childhood and adolescence are at risk for exhibiting a pattern of delinquency that persists from adolescence into adulthood. Intervention efforts designed to prevent chronic delinquency should target youth with co-occurring CD and IC symptoms in childhood and adolescence.

Callous-unemotional traits robustly predict future criminal offending in young men.

Callous-unemotional (CU) traits (e.g., lack of empathy, deficient guilt/remorse, and shallow affect) are a circumscribed facet of the adult psychopathic personality. Although several studies have found that adult psychopathy is a robust predictor of future criminal offending, research exploring the predictive utility of CU traits and future offending are lacking. Moreover, empirical studies examining the predictive utility of psychopathic features often neglect to account for other well-documented risk factors (e.g., prior offending, delinquent peers, marital status), and thus the incremental predictive utility of CU traits remains uncertain. To address these limitations, the current study examined the unique contribution of CU traits in the prediction of future criminal offending in a large ethnically diverse community sample of young adult males (Mean Age = 25.76, SD = .95). Official criminal record information was collected approximately 3.5 years later using multiple sources. Results indicated that after controlling for several other well-established predictors of future offending, men with elevated CU traits had a greater number of arrests and criminal charges and were more likely to be charged with a serious offense and obstruction of justice. CU traits also predicted future theft for Caucasian men, but not African American men. Overall, the results support the notion that CU traits significantly add to the prediction of future offending, even after controlling for several other risk factors.

Refining the Parent-Reported Inventory of Callous-Unemotional Traits in Boys With Conduct Problems

Callous-unemotional (CU) traits have been shown to delineate a unique subgroup of children with severe and persistent conduct problems that seem to have unique etiological origins. However, commonly used measures of CU traits in children may not adequately capture the full range of these characteristics in a developmentally appropriate manner. As a result, the 24-item Inventory of Callous-Unemotional Traits (ICU; self-, parent-, and teacher-report versions; Frick, 2004) was recently developed as a more extensive assessment of CU traits. However, studies to date have focused almost exclusively on the self-report version ICU in adolescents and have identified problems with the factor structure of the measure. The current study is the 1st to examine the factor structure of the parent-report version ICU in a sample of 250 boys (ages 6-12 years) exhibiting significant conduct problems. Initial analyses indicated that factor models reported for the parent-report version of the ICU demonstrated a relatively poor fit to the data. Item response theory techniques were used to develop a more psychometrically sound and efficient short form of the ICU consisting of 2 factors (i.e., Callous and Uncaring) using 12 of the original 24 items. The revised version scores demonstrated high internal consistency, good discrimination across the continuum of the CU construct, and adequate short-term test-retest reliability. The revised measure total score also exhibited evidence of convergent and discriminant validity, although the subscales exhibited some differential correlations with theoretically meaningful constructs. Avenues for future measure refinement and use with children are discussed.

A Validation of the Inventory of Callous-Unemotional Traits in a Community Sample of Young Adult Males

Callous-unemotional (CU) traits have been shown to delineate a subgroup of individuals at high risk for exhibiting severe and persistent criminal behavior. The Inventory of Callous-Unemotional Traits (ICU; Frick 2004) was recently developed as a comprehensive rating scale designed to measure multiple facets of CU traits. However, validation of this measure has been limited to youth in adolescence and emerging adulthood (age range =12–20), leaving questions about the utility of this measure in early adulthood unanswered. The current study evaluated the factor structure of the ICU within a racially diverse and well characterized community sample of adult males (n = 425) using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). While results found the best fitting model to be the three-bifactor structure that has been previously reported in adolescent samples, the fit indices were only marginally acceptable and suggest the need for scale refinement. Total and subscales scores demonstrated significant and distinct associations with relevant external criteria (e.g., delinquency, psychopathy, psychopathology, psychosocial functioning). Implications and directions for future research are discussed.

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.

Antisocial Behavior, Psychopathic Features and Abnormalities in Reward and Punishment Processing in Youth

A better understanding of what leads youth to initially engage in antisocial behavior (ASB) and more importantly persist with such behaviors into adulthood has significant implications for prevention and intervention efforts. A considerable number of studies using behavioral and neuroimaging techniques have investigated abnormalities in reward and punishment processing as potential causal mechanisms underlying ASB. However, this literature has yet to be critically evaluated, and there are no comprehensive reviews that systematically examine and synthesize these findings. The goal of the present review is twofold. The first aim is to examine the extent to which youth with ASB are characterized by abnormalities in (1) reward processing; (2) punishment processing; or (3) both reward and punishment processing. The second aim is to evaluate whether aberrant reward and/or punishment processing is specific to or most pronounced in a subgroup of antisocial youth with psychopathic features. Studies utilizing behavioral methods are first reviewed, followed by studies using functional magnetic resonance imaging. An integration of theory and research across multiple levels of analysis is presented in order to provide a more comprehensive understanding of reward and punishment processing in antisocial youth. Findings are discussed in terms of developmental and contextual considerations, proposed future directions and implications for intervention.

Chronic anger as a precursor to adult antisocial personality features: The moderating influence of cognitive control.

Anger is among the earliest occurring symptoms of mental health, yet we know little about its developmental course. Further, no studies have examined whether youth with persistent anger are at an increased risk of exhibiting antisocial personality features in adulthood, or how cognitive control abilities may protect these individuals from developing such maladaptive outcomes. Trajectories of anger were delineated among 503 boys using annual assessments from childhood to middle adolescence (ages ∼7-14). Associations between these trajectories and features of antisocial personality in young adulthood (age ∼28) were examined, including whether cognitive control moderates this association. Five trajectories of anger were identified (i.e., childhood-onset, childhood-limited, adolescent-onset, moderate, and low). Boys in the childhood-onset group exhibited the highest adulthood antisocial personality features (e.g., psychopathy, aggression, criminal charges). However, boys in this group were buffered from these problems if they had higher levels of cognitive control during adolescence. Findings were consistent across measures from multiple informants, replicated across distinct time periods, and remained when controlling for general intelligence and prior antisocial behavior. This is the first study to document the considerable heterogeneity in the developmental course of anger from childhood to adolescence. As hypothesized, good cognitive control abilities protected youth with persistent anger problems from developing antisocial personality features in adulthood. Clinical implications and future directions are discussed.

Interpersonal Callousness from Childhood to Adolescence: Developmental Trajectories and Early Risk Factors

Youth with a callous interpersonal style, consistent with features of adult psychopathy (e.g., lack of guilt, deceitful), are at risk for exhibiting severe and protracted antisocial behaviors. However, no studies have examined changes that occur in interpersonal callousness (IC) from childhood to adolescence, and little is known about the influence of early child, social, and contextual factors on trajectories of IC. The current study examined distinct patterns of IC across childhood and adolescence and associations with early risk factors. Participants were an at-risk sample of 503 boys (56% African American) assessed annually from around ages 7–15. Analyses examined child (anger dysregulation, fearfulness), social (peer, family, maltreatment), and contextual (psychosocial adversity) factors associated with teacher-reported IC trajectories across childhood and adolescence. Using latent class growth analysis, five trajectories of IC were identified (early-onset chronic, childhood-limited, adolescent-onset, moderate, low). Approximately 10% of boys followed an early-onset chronic trajectory, and a roughly equal percent of youth followed childhood-limited trajectory (10%) or an adolescent-onset trajectory (12%) of IC across development. Specifically, half of the boys with high IC in childhood did not continue to exhibit significant levels of these features into adolescence, whereas an equal proportion of youth with low IC in childhood demonstrated increasing levels during the transition to adolescence. Boys in the early-onset chronic group were characterized by the most risk factors and were differentiated from those with childhood-limited and adolescent-onset IC only by higher conduct problems, fearlessness, and emotional abuse/neglect. Findings are discussed in terms of developmental models of IC and several avenues for early targeted interventions.

5 Why Developmental Criminology Is Still Coming of Age: The Influence of Biological Factors on Within-Individual Change

The chapter reviews the literature on causation as it pertains to developmental/life-course criminology and then applies criteria for causation to research studies on the putative biological causes of crime. Advances and limitations of biological explanation of developmental aspects of offending are reviewed, particularly with an eye on within-individual variations of offending over time.