Cognitive correlates of attention-deficit hyperactivity disorder in children and adolescents with high intellectual ability

Abstract

Background: There is an ongoing debate as to whether attention-deficit hyperactivity disorder (ADHD) in highly intelligent individuals has a similar presentation as in average intelligent individuals. The aim of this study was to examine the cognitive correlates of ADHD in highly intelligent children and adolescents with ADHD. Method: Two independent samples (N = 204 and N = 84) of (1) high intelligence quotient (IQ) (IQ ≥ 120) children and adolescents with ADHD were used, carefully matched on age, gender, ADHD severity, and IQ with (2) control participants with high intelligence, (3) participants with ADHD with an average intelligence (IQ 90-110), and (4) control participants with an average intelligence. These samples were selected from the Dutch node of the International Multicenter ADHD Genetics (NeuroIMAGE) and Tracking Adolescents' Individual Lives Survey (TRAILS) cohorts, respectively, in which a large battery of cognitive tasks was administered. Linear mixed models were used to examine the main effects of ADHD and IQ and their interaction on cognitive performance. Results: ADHD-control group differences were not moderated by IQ; mostly equally large ADHD-control differences in cognitive performance were found for high versus average intelligent groups. The small moderating effects found mostly indicated somewhat milder cognitive problems in highly intelligent individuals with ADHD. Overall, highly intelligent children and adolescents with ADHD performed at the level of the average intelligent control children. Conclusions: Our findings indicate the cognitive profile of ADHD is similar in highly versus average intelligent individuals with ADHD, although ADHD-related cognitive deficits may be easily overlooked in the high intelligence population when compared to the typical (i.e., average intelligent) control group.

Giftedness and Neurodevelopmental Disorders in Children and Adolescents: A Systematic Review

“…Healey et al investigated the correlation between ADHD and creativity and found that there were no differences in the creative ability of the ADHD and the control group. Furthermore, this study showed that, despite the significant levels of ADHD symptomatology displayed by gifted children, the full criteria for ADHD were not met 18 ; similarly, the connection between ADHD and intellectual giftedness or creativity was not established in another study by Healey et al 28 Likewise, Cadenas et al 19 indicated that the highly intelligent group with ADHD performed at the same level as the average intelligent control group on the Wechsler Intelligence Scale for Children or Wechsler Adult Intelligence Scale-III. Diagnostic methods seemed to modify the associations between ADHD and giftedness.…”

Does IQ Influence Association Between Working Memory and ADHD Symptoms in Young Adults?

“…Previous studies conducted with children and adolescents have reported a negative association between ADHD symptoms and WM regardless of IQ-score (Cadenas et al, 2020; Rohrer-Baumgartner et al, 2014). Similar findings were observed in studies in adults, although those studies mostly provided indirect support since none explicitly tested the interaction between WM and IQ (Antshel et al, 2010; Brown et al, 2009).…”

Giftedness and ADHD: A systematic literature review

“…Attention problems were the most common predictors of functional impairments at school: school progress, additional phone calls to parents due to children's school problems, and performance below ability, including in individuals with high IQ. Also in the Netherlands, the study by Cadenas et al (2020) examined the cognitive correlates of ADHD in highly intelligent children and adolescents with ADHD. Two independent samples (n=204 and n=84) were combined into four groups: (a) children and adolescents with high intelligence quotient (IQ ≥120) and ADHD, (b) control participants with high intelligence, (c) ADHD participants with average intelligence (IQ between 90 and 110), and (d) control participants with average intelligence.…”

“…The studies also revealed that the characteristics and symptoms of ADHD manifest similarly in individuals with high and medium intelligence (Cadenas et al, 2020;Katusic et al, 2011;Minahim & Rohde, 2015), which may hinder the identification of giftedness by the family and the school as, in this case, students with high intelligence tend to be recognized only by their manifestation of the attributes of the disorder. In this situation, ADHD generally masks giftedness by increasing the externalization of socio-emotional difficulties and reducing academic performance to medium levels (Mullet & Rinn, 2015).…”