Inhibitory Control, Conduct Problems, and Callous Unemotional Traits in Children with ADHD and Typically Developing Children.

Compared children with CP/ADHD, CPCU/ADHD, ADHD-only, and controls on two measures of inhibitory control: a Simon/flanker task that measured response selection and a stop signal task that measured response inhibition. Results showed: (a) ADHD was associated with both measures of inhibitory control; (b) control children had better overall performance and ADHD-only had worse response selection than the CP groups; and (c) children with CPCU/ADHD had better response inhibition than children with ADHD-only or CP/ADHD. Results suggest inhibitory control dysfunction is associated with ADHD rather than CP and that response inhibition dysfunction distinguishes children with CP/ADHD from children with CPCU/ADHD.

Effects of Behavioral Treatment Modified to Fit Children with Conduct Problems and Callous-Unemotional (CU) Traits.

Research suggests that children with conduct problems (CP) and callous-unemotional (CU) traits show a diminished response to behavior therapy, perhaps due to a reward-oriented, punishment insensitive learning style. Children with CP and CU may benefit from personalizing behavioral treatment for them by emphasizing rewards and de-emphasizing punishments. This hypothesis was tested in a sample of 46 children (78.3% boys), ages 7.0 to 12.6 years (M = 9.3, SD = 1.4). All participants met criteria for ODD and ADHD and 63% also met criteria for CD. Participants were oversampled for high CU, but CU scores ranged from average to high. Children received four weeks of modified behavior therapy that emphasized rewards and de-emphasized punishments and four weeks of treatment as usual, which was standard behavior therapy that balanced rewards and punishments. Treatments were implemented in a summer treatment program and compared using a within-subjects design, with order of treatment counterbalanced. Disruptive behavior was equal or slightly higher in modified behavior therapy than in standard behavior therapy on point system measures, but lower on parent weekly ratings. End of treatment ratings showed both treatments produced significant improvements compared to pre-treatment ratings but did not differ from each other. Personalizing behavior therapy for children with CP and CU produced inconsistent findings relative to standard behavior therapy. Behavior therapy is likely to be a necessary part of treatment for children with CP and CU, but treatment personalization efforts may provide some benefit by addressing other deficits shown by these children.

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 (Mage = 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.

Examining Psychopathic Traits in Children Using the Child Psychopathy Scale - Revised.

Applying the affective dimension of psychopathy to youth has advanced understanding of conduct problems in youth, leading to suggestions that other aspects of psychopathy may do the same. This was addressed in the present study by examining the structure and validity of psychopathic traits in elementary-age children as rated by mothers and teachers on the Child Psychopathy Scale - Revised (CPS-R). Participants were 222 children (80.2% male; Mage = 8.92), the majority (71.6%) of whom met criteria for both ADHD and conduct problems. Confirmatory factor analysis supported a four-factor model consisting of prosocial-empathic (PE), grandiose-manipulative (GM), emotionally volatile (EV), and attentive-planful(AP) factors. The CPS-R demonstrated good criterion validity with well-established measures of child behavior problems and callousness. The EV and AP factors demonstrate incremental validity by moderating the relation between conduct problems and impairment. Latent profiles supported a three-profile solution for mothers and a four-profile solution for teachers, with profiles consisting of one group low, one group moderate, and one high on all measures for both informants, and a fourth group that was high on all measures except CD and limited PE. Profiles differed significantly from each other on callousness and impairment, with limited PE being the best differentiator of youth highest in antisocial behavior based on mother and teacher report. Findings suggest that mothers and teachers may be able to identify children at risk for a more negative trajectory of antisocial behavior, that it is worthwhile to examine multiple psychopathy dimensions (rather than just the affective dimension), and that the CPS-R may be useful to screen for youth who are most likely to display more severe antisocial behavior and impairment.

Effects of Intensive Behavioral Treatment for Children With Varying Levels of Conduct Problems and Callous-Unemotional Traits.

The purpose of this study was to examine whether callous-unemotional (CU) traits moderated the effects of intensive behavior therapy in elementary school-age children with varying levels of conduct problems (CP). Both treatment response (magnitude of change between pre- and posttreatment) and treatment outcomes (likelihood of normalization from treatment) were examined. Participants were 67 children (n = 49 boys, Mage = 9.6 years) with varying levels of CP and CU who participated in an intensive 8-week summer treatment program (STP) in which behavior therapy was delivered to children in recreational and classroom settings and to parents via weekly parent training sessions. Effects of treatment were measured using parent and teacher ratings of oppositional defiant disorder (ODD), conduct disorder (CD), callous behavior, and impairment. Results showed that CU moderated treatment effects for CD and callous behavior but not ODD or impairment. The moderating effects showed some evidence that participants with high CP and high CU before treatment had better treatment responses (larger change between pre- and posttreatment) but worse treatment outcomes (lower likelihood of normalization after treatment). These results suggest that intensive treatment, such as the STP, may be necessary but not sufficient for children with CP and CU traits.

Callous-Unemotional Traits are Uniquely Associated with Poorer Peer Functioning in School-Aged Children.

This study examines externalizing symptoms (attention-deficit/hyperactivity disorder [ADHD], conduct problems, and callous-unemotional [CU] traits) in relation to domains of peer functioning (social competence, loneliness, and close friendship quality), with a specific focus on the role of CU traits. One hundred twenty-four elementary students (grades 3-6; 45% boys) completed multiple measures of peer functioning, and teachers completed measures of externalizing symptoms and social competence. After controlling for demographic variables and other externalizing symptoms, CU traits were significantly associated with poorer peer functioning across all variables except for demands of exclusivity in close friendships. ADHD symptoms were also uniquely associated with poorer social functioning across a number of variables. In contrast, conduct problems were at times associated with better social functioning after controlling for the effects of other externalizing problems. These findings bolster the importance of developing and evaluating social skills interventions for children displaying elevated CU traits.

Behavior therapy and callous-unemotional traits: effects of a pilot study examining modified behavioral contingencies on child behavior.

The conduct problems of children with callous-unemotional (CU) traits (i.e., lack of empathy, lack of guilt/lack of caring behaviors) are particularly resistant to current behavioral interventions, and it is possible that differential sensitivities to punishment and reward may underlie this resistance. Children with conduct problems and CU (CPCU) are less responsive to behavioral punishment techniques (e.g., time-out), whereas reward techniques (e.g., earning points for prizes or activities) are effective for reducing conduct problems. This study examined the efficacy of modified behavioral interventions, which de-emphasized punishment (Condition B) and emphasized reward techniques (Condition C), compared with a standard behavioral intervention (Condition A). Interventions were delivered through a summer treatment program over 7 weeks with an A-B-A-C-A-BC-A design to a group of 11 children (7-11 years; 91% male). All children were diagnosed with either oppositional defiant disorder or conduct disorder, in addition to attention-deficit hyperactivity disorder. Results revealed the best treatment response occurred during the low-punishment condition, with rates of negative behavior (e.g., aggression, teasing, stealing) increasing over the 7 weeks. However, there was substantial individual variability in treatment response, and several children demonstrated improvement during the modified intervention conditions. Future research is necessary to disentangle treatment effects from order effects, and implications of group treatment of CPCU children (i.e., deviancy training) are discussed.

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.

The comparative psychophysics of complex shape perception.

The authors compared the complex shape perception of humans and monkeys. Members of both species participated in a Same-Different paradigm in which they judged the similarity of shape pairs that could be variations of the same underlying prototype. For both species, similarity gradients were found to be steep going out from the transformational center of psychological space. In contrast, similarity gradients were found to be flat going from the periphery in toward the center of psychological space. These results show that there are important common principles in the shape-perception and shape-comparison processes of humans and monkeys. The same general organization of psychological space is obtained. The same quantifiable metric of psychological distance is applied. Established methods for creating controlled shape variation have the same effect on both species' similarity judgments. The member of the to-be-judged pair of shapes that is peripheral in psychological space controls the strength of the perceived similarity of the pair. The results have broader implications for the comparative study of perception and categorization.

The comparative psychology of same-different judgments by humans (Homo sapiens) and monkeys (Macaca mulatta).

The authors compared the performance of humans and monkeys in a Same-Different task. They evaluated the hypothesis that for humans the Same-Different concept is qualitative, categorical, and rule-based, so that humans distinguish 0-disparity pairs (i.e., same) from pairs with any discernible disparity (i.e., different); whereas for monkeys the Same-Different concept is quantitative, continuous, and similarity-based, so that monkeys distinguish small-disparity pairs (i.e., similar) from pairs with a large disparity (i.e., dissimilar). The results supported the hypothesis. Monkeys, more than humans, showed a gradual transition from same to different categories and an inclusive criterion for responding Same. The results have implications for comparing Same-Different performances across species--different species may not always construe or perform even identical tasks in the same way. In particular, humans may especially apply qualitative, rule-based frameworks to cognitive tasks like Same-Different.

Prototype abstraction by monkeys (Macaca mulatta).

The authors analyze the shape categorization of rhesus monkeys (Macaca mulatta) and the role of prototype- and exemplar-based comparison processes in monkeys' category learning. Prototype and exemplar theories make contrasting predictions regarding performance on the Posner-Homa dot-distortion categorization task. Prototype theory--which presumes that participants refer to-be-categorized items to a representation near the category's center (the prototype)--predicts steep typicality gradients and large prototype-enhancement effects. Exemplar theory--which presumes that participants refer to-be-categorized items to memorized training exemplars-predicts flat typicality gradients and small prototype-enhancement effects. Across many categorization tasks that, for the first time, assayed monkeys' dot-distortion categorization, monkeys showed steep typicality gradients and large prototype-enhancement effects. These results suggest that monkeys--like humans--refer to-be-categorized items to a prototype-like representation near the category's center rather than to a set of memorized training exemplars.