Greater delay discounting among girls, but not boys, with ADHD correlates with cognitive control

ABSTRACT

Cognitive neuroscience models suggest both reward valuation and cognitive control contribute to reward-based decision-making. The current study examined the relationship between cognitive control and delay discounting (i.e., choosing smaller, immediate over larger, delayed rewards) in a large sample of boys and girls diagnosed with attention-deficit/hyperactivity disorder (ADHD; N = 95) and typically developing control children (TD; N = 59). Specifically, we examined performance on multiple measures of cognitive control (i.e., Go/No-Go task, Stop Signal task, and Spatial Span task) and delay discounting (i.e., Classic Delay Discounting and Real-Time Delay Discounting tasks), as well as the relationship between these measures. Results indicated that sex moderated the effects of group on task performance. Specifically, girls with ADHD, but not boys with the disorder, exhibited atypical delay discounting of real-time rewards. Results from correlational analyses indicated that delay discounting and cognitive control were not significantly correlated in the overall sample. Multiple regression analyses demonstrated that among girls with ADHD poorer spatial working memory and inhibitory control predicted greater real-time discounting. Collectively, findings provide support for distinct patterns of cognitive control and delay discounting among school-aged girls and boys with ADHD. Additionally, findings suggest that among girls with ADHD, those who exhibit relatively poor working memory and inhibitory control might be a particularly vulnerable subgroup with the greatest propensity to exhibit maladaptive decision-making.

KEYWORDS:

• ADHD
• decision-making
• delay discounting
• cognitive control
• executive function

Acknowledgments

This work was supported in part by grants from the National Institute of Mental Health (R01 MH078160; R01 MH085328, K23 MH101322, U54 HD079123) and the Johns Hopkins University School of Medicine Institute for Clinical and Translational Research National Institutes of Health/National Center for Research Resources Clinical and Translational Science Award program UL1 TR 000424-06..

Disclosure statement

No potential conflict of interest was reported by the authors.

Notes

¹ With SSD in the model, this result remains significant: F(6, 145) = 3.2, p = .006.

² With SSD in the model, results essentially remain the same such that the overall model was significant, F(4, 24) = 4.5, p = .008, and both spatial span backward (p = .027) and GNG commission error rate (p = .004) were unique predictors of discounting, whereas stop signal SSD did not account for unique variance (p = .906). One notable change is that GNG tau was also significant in the model with SSD (p = .043), but not in the model with SSRT (p = .092). This is likely due to greater shared variance between SSRT and GNG tau, which are both reaction time measures that are more highly correlated (r = .441) than SSD and GNG tau (r = −.205).

³ Results with SSD in the model are essentially the same such that the main effect of diagnosis remained significant, β = −.097, p = .031, whereas the Diagnosis × Sex interaction was no longer significant, β = .101, p = .063, although the change in p-value was negligible (previously p = .035). Furthermore, none of the measures of cognitive control were unique predictors of real-time discounting (all ps >.16).

Additional information

Funding

This work was supported in part by grants from the National Institute of Mental Health (R01 MH078160; R01 MH085328, K23 MH101322, U54 HD079123) and the Johns Hopkins University School of Medicine Institute for Clinical and Translational Research National Institutes of Health/National Center for Research Resources Clinical and Translational Science Award program UL1 TR 000424-06