Cecilia Wåhlstedt

Heterogeneity in ADHD: neuropsychological pathways, comorbidity and symptom domains.

The aim of the present study was to investigate different neuropsychological impairments and comorbid behavioral problems in relation to symptoms of Attention-Deficit/Hyperactivity Disorder (ADHD), studying the independent effects of different functions as well as specific relations to symptoms of hyperactivity/impulsivity and inattention. A community-based sample of school children (n = 182; the higher end of the ADHD symptom range was oversampled) completed neuropsychological tasks designed to measure executive function (EF), state regulation and delay aversion. Behavioral symptoms were measured through parental and teacher ratings of the DSM-IV criteria for ADHD and Oppositional Defiant Disorder (ODD). Both categorical and dimensional analyses were used to acquire a deeper understanding of ADHD. The results supported the notion that EF and state regulation constitute independent pathways to ADHD, primarily to symptoms of inattention. In addition, the present study points to the importance of viewing ADHD as a heterogeneous condition also with regard to the differential impact of neuropsychological functioning and comorbidity on different ADHD symptom groups and the two ADHD symptom domains.

ADHD Symptoms and Executive Function Impairment: Early Predictors of Later Behavioral Problems

This longitudinal study investigated ADHD symptoms and EF impairments in terms of continuity and cross-domain associations, as well as their predictive relations to a range of socioemotional problem behaviors. We applied a factorial ANOVA design to study additive and interactive effects in a sample of non-clinical preschool children (N = 87) and complemented these analyses with group contrasts. The results showed that early ADHD symptoms and EF impairments acted as predictors of continuing problems within each domain. However, it was only ADHD symptoms that predicted other aspects of socioemotional functioning such as dysfunctional emotional regulation and lower levels of social competence. There was no indication of interactive effects on any measure. In conclusion, our results showed that both ADHD symptoms and impaired EF act as early predictors of problem behaviors, although it is clear that predictions based on ADHD symptoms encompass a wider range of problems in early school age children.

DSM-IV-Defined Inattention and Sluggish Cognitive Tempo: Independent and Interactive Relations to Neuropsychological Factors and Comorbidity

The aim of the present study was to investigate the independent relations of DSM-IV-defined inattention and behaviors characteristic of sluggish cognitive tempo (SCT) to neuropsychological factors and problem behaviors often comorbid with attention deficit/hyperactivity disorder (ADHD). By controlling for symptoms of DSM-IV-defined inattention, unique relations to SCT could be ascertained. Additionally, interactive relations of DSM-IV-defined inattention and SCT were of interest. A community-based sample of school children (N = 209; the higher end of the ADHD-symptom range was oversampled) completed neuropsychological tasks designed to measure executive function (EF), sustained attention, and state regulation. Behavioral symptoms were measured using parental and teacher ratings of the DSM-IV criteria for ADHD and Oppositional Defiant Disorder (ODD). The results showed that these two domains of inattention, DSM-IV-defined inattention and SCT, have neuropsychological processes and comorbid behavioral problems in common. However, when controlling for the overlap, DSM-IV-defined inattention was uniquely related to EF and state regulation, while SCT was uniquely related to sustained attention. In addition, the results showed an interactive relation of DSM-IV-defined inattention and SCT to ODD. Findings from the present study support the notion that DSM-IV-defined inattention constitutes a somewhat heterogeneous condition. Such results can further our theoretical understanding of the neuropsychological impairments and comorbid behavioral problems associated with ADHD symptoms.

Neuropsychological deficits in relation to symptoms of ADHD: independent contributions and interactions.

The aim of the present study was to investigate possible independent and combined effects of inhibitory control, delay aversion, and RT variability in relation to symptoms of hyperactivity/impulsivity and inattention. A community-based sample of school children (N = 111) completed neuropsychological tasks designed to measure inhibitory control, delay aversion, and RT variability. Behavioral symptoms were measured through parental and teacher ratings of the DSM-IV criteria for ADHD and ODD. The results showed that inhibitory control and RT variability were primarily related to symptoms of inattention rather than hyperactivity/impulsivity. Further, out of the three neuropsychological factors studied, only inhibitory control contributed uniquely to the variance of ADHD symptoms. However, significant interaction effects of delay aversion and RT variability on symptoms of both hyperactivity/impulsivity and inattention were found. This study shows the importance of searching for possible combined effects of neuropsychological factors to learn more about the different pathways that lead to ADHD symptoms in children.

The Specificity and Independent Contribution of Inhibition, Working Memory, and Reaction Time Variability in Relation to Symptoms of ADHD and ASD

Objective: The aim of the present study was to investigate the specificity of inhibition, working memory (WM), and reaction time variability (RTV) in relation to symptoms of ADHD and autism spectrum disorder (ASD). Method: A community-based sample of schoolchildren aged 7 to 9 years (N = 200) completed tasks designed to measure inhibition, WM, and RTV. Results: All neuropsychological functions were related to symptoms of both ADHD and ASD. The results from regression analyses showed that inhibition and RTV were related specifically to ADHD symptoms when controlling for symptoms of ASD. Regarding WM, no specific association with either symptom domain was evident after controlling for the other. Furthermore, independent contributions of inhibition and RTV were found in relation to ADHD symptoms after controlling for ASD symptoms. Conclusion: The present study underscores the relevance of controlling for ADHD symptoms when examining ASD symptoms in relation to neuropsychological functions.

Callous–unemotional traits affect adolescents' perception of collaboration

Background How is the perception of collaboration influenced by individual characteristics, in particular high levels of callous–unemotional (CU) traits? CU traits are associated with low empathy and endorsement of negative social goals such as dominance and forced respect. Thus, it is possible that they could relate to difficulties in interpreting that others are collaborating based on a shared goal. Methods In the current study, a community sample of 15‐ to 16‐year olds participated in an eye tracking task measuring whether they expect that others engaged in an action sequence are collaborating, depending on the emotion they display toward each other. Positive emotion would indicate that they share a goal, while negative emotion would indicate that they hold individual goals. Results When the actors showed positive emotion toward each other, expectations of collaboration varied with CU traits. The higher adolescents were on CU traits, the less likely they were to expect collaboration. When the actors showed negative emotion toward each other, CU traits did not influence expectations of collaboration. Conclusions The findings suggest that CU traits are associated with difficulty in perceiving positive social interactions, which could further contribute to the behavioral and emotional problems common to those with high CU traits.