The callousness pathway to severe violent delinquency

Children and adolescents who exhibit a callous interpersonal style seem to be at risk for developing severe forms of violent behavior. Theoretical models suggest that children with low levels of temperamental fearfulness may be at increased risk for developing callous traits because they are relatively unaffected by punishment. This study examines hypotheses about the callousness pathway to severe violent delinquency in a cross‐sectional sample of 169 (97=males, 72=females) adjudicated adolescents. Structural equation modeling is used to test mediation models regarding the relation between temperamental fear, punishment concern, callousness, and severe violent delinquency. The findings of the study indicate that the relation between low levels of temperamental fear and increased callousness is mediated by a lack of concern about being punished for aggressive acts. Although low levels of fear and punishment concern were both related to increased levels of severe violent delinquency, increased levels of callousness mediated these relations. All findings remained significant after controlling for the potential confounds of gender, race, and social desirability. The results provide a heuristic for understanding the callousness pathway to severe violent behavior in youth. However, longitudinal investigations replicating these results are necessary before firm conclusions can be drawn. Aggr. Behav. 32:590–598, 2006. © 2006 Wiley‐Liss, Inc.     

A general approach to causal mediation analysis

Traditionally in the social sciences, causal mediation analysis has been formulated, understood, and implemented within the framework of linear structural equation models. We argue and demonstrate that this is problematic for 3 reasons: the lack of a general definition of causal mediation effects independent of a particular statistical model, the inability to specify the key identification assumption, and the difficulty of extending the framework to nonlinear models. In this article, we propose an alternative approach that overcomes these limitations. Our approach is general because it offers the definition, identification, estimation, and sensitivity analysis of causal mediation effects without reference to any specific statistical model. Further, our approach explicitly links these 4 elements closely together within a single framework. As a result, the proposed framework can accommodate linear and nonlinear relationships, parametric and nonparametric models, continuous and discrete mediators, and various types of outcome variables. The general definition and identification result also allow us to develop sensitivity analysis in the context of commonly used models, which enables applied researchers to formally assess the robustness of their empirical conclusions to violations of the key assumption. We illustrate our approach by applying it to the Job Search Intervention Study. We also offer easy-to-use software that implements all our proposed methods.     

Building an evidence base for DSM-5 conceptualizations of oppositional defiant disorder and conduct disorder: introduction to the special section

The DSM-5 ADHD and Disruptive Behavior Disorders Work Group recently outlined a research agenda designed to support possible revisions to the diagnostic criteria for oppositional defiant disorder (ODD) and conduct disorder (CD). Some of the areas in need of further investigation include (a) examining the clinical utility of the current diagnostic system in girls, (b) further clarifying the developmental progression from ODD to CD, (c) determining whether facets of ODD symptoms can help explain heterotypic continuity and enhance predictive validity, (d) evaluating the clinical utility of a new subtyping scheme for CD on the basis of the presence of callous-unemotional traits, and (e) comparing the clinical utility of dimensional versus categorical conceptualizations of ODD and CD. This special section was organized in an attempt to provide data on these issues using a diverse array of longitudinal data sets consisting of both epidemiological and clinic-based samples that collectively cover a large developmental span ranging from childhood through early adulthood.     

ODD dimensions, ADHD, and callous-unemotional traits as predictors of treatment response in children with disruptive behavior disorders

To answer several questions pertinent to DSM-V, the authors examined the predictive validity of pretreatment oppositional defiant disorder (ODD) dimensions, attention-deficit/hyperactivity disorder (ADHD), and callous-unemotional (CU) traits in relation to several treatment outcomes in 177 children diagnosed with ODD or conduct disorder (CD). Multiple informants completed diagnostic interviews and rating scales at 6 assessment points (pretreatment to 3-year follow-up) to document emotional and behavioral outcomes. After controlling for pretreatment CD, the ODD dimension of hurtfulness was related to treatment-resistant CD, delinquent behaviors, and externalizing problems. In contrast, the ODD dimension tapping irritability was associated with treatment-resistant ODD, internalizing problems, and global functional impairment following treatment. Whereas pretreatment ADHD was associated with posttreatment ODD and social problems, it was unrelated to posttreatment CD symptoms and diagnosis. Contrary to predictions, CU traits were unrelated to any posttreatment outcomes after controlling for other covariates. These findings remained after controlling for measures of pretreatment global functional impairment.     

Gender bias triggers diverging science interests between women and men: The role of activity interest appraisals

Women leave science fields at greater rates than men, and loss of interest is a key motivator for leaving. Although research widely demonstrates effects of gender bias on other motivational processes, whether gender bias directly affects feelings of interest toward science activities is unknown. We used a false feedback paradigm to manipulate whether women (Study 1) and men (Study 2) participants perceived the reason for feedback as due to pro-male bias. Because activity interest also depends on how students approach and perform the activity, effects of biased feedback on interest appraisals were isolated by introducing gender bias only after the science activity was completed. When the feedback was perceived as due to pro-male bias, women (Study 1) reported lower interest and men (Study 2) reported greater interest in the science activity, and interest, in turn, positively predicted subsequent requests for career information in both studies. Implications for understanding diverging science interests between women and men are discussed.     

Monkeys display classic signatures of human symbolic arithmetic

Non-human primates compare quantities in a crude manner, by approximating their values. Less is known about the mental transformations that non-humans can perform over approximate quantities, such as arithmetic transformations. There is evidence that human symbolic arithmetic has a deep psychological connection with the primitive, approximate forms of quantification of non-human animals. Here, we ask whether the subtle performance signatures that humans exhibit during symbolic arithmetic also bear a connection to primitive arithmetic. Specifically, we examined the problem size effect, the tie effect, and the practice effect—effects which are commonly observed in children’s math performance in school. We show that, like humans, monkeys exhibited the problem size and tie effects, indicating commonalities in arithmetic algorithms with humans. Unlike humans, however, monkeys did not exhibit a practice effect. Together, these findings provide new evidence for a cognitive relation between non-symbolic and symbolic arithmetic.     

Are Episodic Buffer Processes Intact in ADHD? Experimental Evidence and Linkage with Hyperactive Behavior

Working memory deficits are present in a substantial proportion of children with ADHD, and converging evidence links these deficits with ADHD-related behavioral and functional impairments. At the same time, working memory is not a unitary construct, and evidence is lacking regarding the role of several components of this system in ADHD. Preclinical behavioral studies are needed to fractionate the multicomponent working memory system, determine which specific subcomponent(s) are impaired in ADHD, and more importantly link these subcomponent(s) with specific ADHD-related behavioral symptoms/functional impairments. The current study reflects one piece of that puzzle, and focuses on the episodic buffer component of working memory. Across multiple testing days, a well-characterized sample of 86 children ages 8–13 (M=10.52, SD=1.54; 34 girls; 64% Caucasian/Non-Hispanic) with ADHD (n=49) and without ADHD (n=37) completed three counterbalanced working memory tests that were identical in all aspects except the key subcomponent process (phonological, visuospatial, episodic buffer). Gross motor movement during these and control tasks were measured using 4 high-precision actigraphs. There was no evidence of group differences in gender, age, SES, or IQ. Bayesian mixed-model ANOVAs indicated that the ADHD group performed significantly worse on all three working memory tests (d=1.17–1.44) and was significantly more hyperactive than controls (d=0.66–1.05) during the visuospatial and episodic buffer tests. In contrast, the ADHD and Non-ADHD groups were equivalent with regard to effects of episodic buffer demands on performance and hyperactive behavior. The most parsimonious conclusion is that the episodic buffer is likely intact in ADHD, and unrelated to ADHD hyperactivity symptoms.     

Heterogeneity in ADHD: Neurocognitive predictors of peer,family, and academic functioning

Childhood attention-deficit/hyperactivity disorder (ADHD) is associated with impairments in peer, family, and academic functioning. Although impairment is required for diagnosis, children with ADHD vary significantly in the areas in which they demonstrate clinically significant impairment. However, relatively little is known about the mechanisms and processes underlying these individual differences. The current study examined neurocognitive predictors of heterogeneity in peer, family, and academic functioning in a well-defined sample of 44 children with ADHD aged 8–13 years (M = 10.31, SD = 1.42; 31 boys, 13 girls; 81% Caucasian). Reliable change analysis indicated that 98% of the sample demonstrated objectively-defined impairment on at least one assessed outcome measure; 65% were impaired in two or all three areas of functioning. ADHD children with quantifiable deficits in academic success and family functioning performed worse on tests of working memory (d = 0.68 to 1.09), whereas children with impaired parent-reported social functioning demonstrated slower processing speed (d = 0.53). Dimensional analyses identified additional predictors of peer, family, and academic functioning. Working memory abilities were associated with individual differences in all three functional domains, processing speed predicted social functioning, and inhibitory control predicted family functioning. These results add to a growing literature implicating neurocognitive abilities not only in explaining behavioral differences between ADHD and non-ADHD groups, but also in the substantial heterogeneity in ecologically-valid functional outcomes associated with the disorder.