The heritability of antisocial behavior: A meta-analysis of twin and adoption studies

In this paper, we describe a quantitative summary of 12 twin (n=3795 twin pairs and 3 adoption studies=338 adoptees) published since 1975 which provided 21 estimates of the heritability of antisocial behavior. Medium to large effect sizes were found for genetic influences across studies, with approximately 50% of the variance in measures of antisocial behavior attributable to genetic effects. Although effect sizes did not vary across different definitions of antisocial behavior (criminality, aggression, or antisocial personality), significantly larger estimates of genetic effect were found for severe manifestations of antisocial behavior. The importance of severity was further underscored by the significantly larger effects obtained in studies using clinic-referred samples compared to the effects obtained in studies using volunteer samples. Demographic characteristics of the samples did not influence effect sizes, although studies using more stringent methodology tended to find larger effects. These results must be interpreted in light of the small literature that was suitable for the meta-analysis due to numerous methodological limitations in existing studies.     

The Association between Anxiety and Psychopathy Dimensions in Children

Although several theoretical models posit that low levels of anxiety are a risk factor for psychopathy and antisocial behavior, a number of studies have reported elevated levels of anxiety among antisocial individuals. Nevertheless, most investigators in this literature have not distinguished between fearfulness and trait anxiety or attempted to separate the antisocial lifestyle dimension from the callous and unemotional dimension of psychopathy. In a study of clinically referred children (N = 143), we found that (a) measures of trait anxiety and fearlessness (low fearfulness) exhibited low correlations; (b) conduct problems tended to be positively correlated with trait anxiety, whereas callous and unemotional traits tended to be negatively correlated with trait anxiety; and (c) controlling statistically for the effects of one dimension increased the divergent correlations of the other dimension with both trait anxiety and fearful inhibition. These findings bear potentially important implications for the diagnosis and etiology of psychopathy and antisocial behavior and suggest that distinctions between trait anxiety and fearful inhibition, as well as between the two dimensions of psychopathy, may help to clarify longstanding confusion in this literature.     

The role of memory in attenuations of the suffix effect

Various properties attenuate the auditory suffix effect. These properties may improve recall by allowing the suffix to be excluded from the auditory store (or stores) used for immediate ordered recall, or they may improve recall even though the suffix is included in the auditory store. Nine items were presented, with the last item being either a suffix or another item to be recalled. In Experiment 1, the impairment in recall of the previous items produced by presenting a to-be-recalled last item in a different voice was the same as the impairment produced by presenting a suffix in a different voice. The same result was found in Experiment 2 for presenting the last item in a different spatial location and in Experiment 3 for delaying the presentation of the last item. Apparently the attenuating properties improve recall through memorial factors, and not by allowing the suffix to be excluded from the auditory store.     

A better stopping rule for conventional statistical tests

The goal of some research studies is to demonstrate the existence of an effect. Statistical testing, withp less than .05, is one criterion for establishing the existence of this effect. In this situation, the fixedsample stopping rule, in which the number of subjects is determined in advance, is impractical and inefficient. This article presents a sequential stopping rule that is practical and about 30% more efficient: Once a minimum number of subjects is tested, stop withp less than .01 or greater than .36; otherwise, keep testing. This procedure keeps alpha at .05 and can be adjusted to fit researchers’ needs and inclinations.     

The intergenerational link to antisocial behavior: Effects of paternal contact

We investigated the relationship between paternal antisocial behavior and child conduct problems and we tested whether the degree of contact between father and child moderated the intergenerational link to antisocial behavior. Subjects were 92 children between the ages of 6 and 13 referred to an outpatient mental health clinic. There was a significant association between Antisocial Personality Disorder (APD) in fathers and a diagnosis of conduct problems in their children. However, the relationship between paternal APD and conduct problems in offspring was not dependent on whether or not the father was in the home or on the degree of paternal contact with their child. The theoretical implications of these findings for explaining the intergenerational link to antisocial behavior in terms of observational learning were discussed.     

Agreement of parent and teacher rating scales with comprehensive clinical assessments of attention deficit disorder with hyperactivity

Forty-one clinic-referred children were given the DSM-III diagnosis of attention deficit disorder with hyperactivity (ADD/H) based on structured diagnostic interviews of the child and mother and on two teacher and two parent rating scales. The degree of agreement between diagnostic classification of ADD/H based solely on criterion scores on each rating scale and classification based on the comprehensive clinical assessments that included use of the same rating scaleswas assessed by comparing the ratings of the 41 children with ADD/H to those of 47 clinic-referred children given other diagnoses or no diagnosis. The accuracy of classification was highly similar across scales. Increasing the cutoff score increased the acing true positives. Using the point of intersection of these two curves to choose the optimal cutoff scores resulted in 70–75% accurate classification and 25–30% misclassification of children given clinical diagnoses of ADD/H. This rate of misclassification suggests that rating scales alone should not be used to classify ADD/H for most clinical and research purposes, especially because the method of comparison used in this study favored finding a high degree of correspondence.     

The Association between Callous-Unemotional Traits and Behavioral and Academic Adjustment in Children: Further Validation of the Inventory of Callous-Unemotional Traits

Callous-unemotional (CU) traits have been associated with problems in behavioral adjustment in past research which has led to proposals to include them in diagnostic classification systems for child behavior problems. In the current study, the factor structure of a comprehensive measure of CU traits was tested in a sample of 540 Italian children in grades 6 and 8. Consistent with past factor analyses in other countries, CU traits could be described as having three subfactors (i.e., callousness, uncaring, unemotional) which load on an overarching general factor. Importantly, this factor structure was invariant across gender and grade. Consistent with past studies, CU traits were positively associated with school behavior problems, bullying, and reactive aggression and this was largely accounted for by the callousness and uncaring subscales. The current results advance past work in showing that these associations extend to cyberbullying and to bullying reported by both self-report and by peer nominations. Further, CU traits were also associated with lower levels of academic achievement, and this was also largely accounted for by the callousness and uncaring dimensions. Finally, although the unemotional subscale did not show consistent associations with problems in behavioral or academic adjustment, it did contribute independently to the prediction (negatively) of peer-reported prosocial behaviors.     

Look Here! The Development of Attentional Orienting to Symbolic Cues

Although much research has examined the development of orienting to social directional cues (e.g., eye gaze), little is known about the development of orienting to nonsocial directional cues, such as arrows. Arrow cues have been used in numerous studies as a means to study attentional orienting, but the development of children's understanding of such cues has not previously been examined. It remains unclear to what extent the social nature of a cue is important for directing attention; further, it is unknown whether symbolic understanding is necessary for young children to be cued by symbols such as arrows. The present investigation explored when and how arrows cue children's attention. Our results suggest that children younger than 5 years of age orient their attention using the perceptual properties of arrows, and it is not until sometime after 5 years of age that children use the conceptual meaning of arrows to orient their attention. Understanding of the directional meaning of arrows may develop through both exogenous and endogenous orienting; we discuss possible contributions of the compression-based and selection-based learning systems.