Assessment of 'Cool' and 'Hot' Executive Skills in Children with ADHD: The Role of Performance Measures and Behavioral Ratings

Emotion dysregulation and depressive symptoms mediate the association between inhibitory control difficulties and aggressive behaviour in children with ADHD

Background/objectives

Impulsive aggressive behaviour, although not a core symptom, is often part of the clinical presentation of attention-deficit/hyperactivity disorder (ADHD). Recently, impulsive aggression has been attributed to emotion dysregulation, which is currently conceptualised as a transdiagnostic factor and seems to contribute to the co-occurrence of other problems in ADHD. Thus, this study investigated the presence of impulsive aggressive behaviour and explored whether emotion dysregulation mediates the relationship between inhibitory control difficulties and aggressive behaviour in children with ADHD. Because ADHD may act as a risk factor for the development of other conditions, such as internalising problems, we aimed to understand whether depressive symptoms contribute to this relationship.

Methods

Seventy-two children were recruited from a hospital and the community, 38 of whom had ADHD and 34 were typically developing (TD). Parents completed the Child Behaviour Checklist, the Behaviour Rating Inventory of Executive Function, and the Emotion Regulation Checklist. Simple mediation and serial mediation models were performed to test our hypotheses.

Results

Aggressive behaviour was significantly higher in ADHD children compared to TD children. Emotion dysregulation fully mediated the relationship between inhibitory control difficulties and aggressive behaviour in ADHD children. Adding depressive symptoms to the model increased the explained variance in aggressive behaviour.

Conclusion

The main result of our study supports the role of emotion dysregulation and depressive symptoms in mediating the relationship between inhibitory control difficulties and impulsive aggressive behaviour in children with ADHD. This highlights that aggressive behaviour is, in part, a result of the inability of the child to appropriately regulate their emotions. Future interventions may be tailored to improve emotion regulation skills to address aggressive behaviour.

Do executive functions differentiate Iranian children with attention-deficit/hyperactivity disorder with and without comorbid obesity?

OBJECTIVE

To compare multiple dimensions of executive function between children with attention-deficit/hyperactivity disorder (ADHD) with and without comorbid obesity.

METHOD

Participants were 90 Iranian children (ages 8-13, 50% female) who were equally dispersed across three study groups: typically developing (TD), ADHD with obesity (ADHD+O), and ADHD without obesity (ADHD-O). Study participants were administered a comprehensive battery of Iranian-adapted "cool" executive function tasks including Digit Span from the Wechsler Intelligence Scale for Children-Fifth Edition (WISC-V), Victoria Stroop Test (VST), Wisconsin Card Sorting Test (WCST), Tower of London, and dot-probe task (i.e., a task of attentional bias). Parents completed the Children's Scale for Future Thinking Questionnaire, which assesses future-oriented cognition (e.g., saving, planning, episodic foresight, delay of gratification), aligning more with "hot" executive functions. Groups were compared using multivariate and post-hoc univariate general linear models.

RESULTS

Significant group effects were observed for all executive function variables, broadly with the gradient pattern of TD > ADHD-O > ADHD+O. ADHD+O had poorer performances than ADHD-O for WISC-V Digit Span (d = -0.84), WCST Categories Completed (d = -0.55) and Perseverative Responses (d = 1.15), VST Interference Errors (d = 0.83) and Interference Time (d = 1.38), and Dot-Probe Task (d = 0.84). Relative to the ADHD-O group, ADHD+O had also poorer parent-reported Prospective Memory (d = -0.62), Episodic Foresight (d = -0.63), and Delay of Gratification (d = -0.54).

CONCLUSIONS

Children with ADHD-O have poorer executive functioning than those without obesity. We observed stronger effects for "cool" rather than "hot" domains of executive function, though this could be due to the former being performance-based and the latter parent-reported.