Investigating the Impact of Cognitive Load and Motivation on Response Control in Relation to Delay Discounting in Children with ADHD

Abstract

Attention-deficit/hyperactivity disorder (ADHD) is characterized by deficits in impulse control across a range of behaviors, from simple actions to those involving complex decision-making (e.g., preference for smaller-sooner versus larger later rewards). This study investigated whether changes in motor response control with increased cognitive load and motivational contingencies are associated with decision-making in the form of delay discounting among 8-12 year old children with and without ADHD. Children with ADHD (n = 26; 8 girls) and typically developing controls (n = 40; 11 girls) completed a standard go/no-go (GNG) task, a GNG task with motivational contingencies, a GNG task with increased cognitive load, and two measures of delay discounting: a real-time task in which the delays and immediately consumable rewards are experienced in real-time, and a classic task involving choices about money at longer delays. Children with ADHD, particularly girls, exhibited greater delay discounting than controls during the real-time discounting task, whereas diagnostic groups did not significantly differ on the classic discounting task. The effect of cognitive load on response control was uniquely associated with greater discounting on the real-time task for children with ADHD, but not for control children. The effect of motivational contingencies on response control was not significantly associated with delay discounting for either diagnostic group. The findings from this study help to inform our understanding of the factors that influence deficient self-control in ADHD, suggesting that impairments in cognitive control may contribute to greater delay discounting in ADHD.

Examining children's ability to delay reward: Is the delay discounting task a suitable measure?

“…In the present study, after controlling for differences in IQ, there was a trend for children with elevated risk of ADHD as assessed by teacher report to show steeper discounting in the DD task than children at low risk, but not lower scores on the DoG task. The former finding corroborates and extends those studies in which children with clinically diagnosed ADHD show steeper discounting of real rewards over short delays (e.g., Martinelli et al, ; Yu et al, ). Unlike those studies, the present task used hypothetical rewards over much longer delay periods and tested children with elevated risk of ADHD on the basis of teacher ratings rather than on a clinical diagnosis.…”

“…Wilson, Mitchell, Musser, Schmitt, and Nigg () administered a DD task to 7‐ to 9‐year‐olds with and without a diagnosis of ADHD and found that discount functions were significantly steeper for the ADHD group, although this effect did not survive controlling for IQ. By comparison, Rosch and Mostofsky (), using the same hypothetical DD task as Wilson et al, found no difference in performance between an ADHD group and typically developing controls aged 8 to 12 years (see also Antonini, Becker, Tamm, & Epstein, ; Martinelli, Mostofsky, & Rosch, ).…”

“…Third, and finally, we examined the link between DD and measures of sensation seeking and ADHD, traits that have been associated with DD in adolescents. As described above, although a number of studies have found a difference between the discount rates of adolescents with ADHD and those od typically developing controls (Barkley et al, ; Demurie, Roeyers, Baeyens, & Sonuga Barke, ; Sonuga‐Barke, Taylor, Sembi, & Smith, ), in studies with children, the pattern of findings has been more mixed (Martinelli et al, ; Rosch & Mostofsky, ; Scheres et al, ; Wilson et al, ). We did not use an ADHD group in the study, but we did gather teacher ratings of ADHD traits in our sample in order to examine the relation between such ratings and children's performance on the DoG and DD tasks.…”

“…Studies using this approach have, by necessity, used very short delays (e.g., 30–60 s) and small rewards (e.g., 10 cents). These studies, too, though, have also reported mixed results with regard to differences between typically developing children and those with ADHD (Martinelli et al, ; Scheres et al, ; Yu, Sonuga‐Barke, & Liu, ).…”

Decline of prefrontal cortical-mediated executive functions but attenuated delay discounting in aged Fischer 344 × brown Norway hybrid rats

“…During adolescence and early adulthood, the ability to wait for reward, or delay gratification, is generally considered adaptive and is associated with better overall life outcomes (Banich et al, 2013; Steinbeis et al, 2016). Indeed, children and adolescents, as well as individuals with psychiatric conditions such as attention deficit hyperactive disorder and substance use disorders, reliably display elevated preference for immediate over delayed rewards (Martinelli et al, 2016; Perry and Carroll, 2008; Scheres et al, 2013, 2008). These disorders are also associated with, and have been in part attributed to, prefrontal cortical-mediated cognitive deficits.…”