Reduced intrasubject variability with reinforcement in boys, but not girls, with ADHD: Associations with prefrontal anatomy

Abstract

This study examined the impact of motivational contingencies (reinforcement and punishment) on Go/No-Go (GNG) task performance in girls and boys with ADHD relative to typically developing (TD) children and associations with prefrontal anatomy. Children ages 8–12 with ADHD (n=107, 36 girls) and TD controls (n=95, 34 girls) completed a standard and a motivational GNG task and associations with prefrontal cortex (PFC) surface area were examined. Intrasubject variability (ISV) was lower during the motivational compared to the standard GNG among TD girls and boys, and boys with ADHD, but not among girls with ADHD. A greater reduction in ISV was associated with greater PFC surface area among children with ADHD. This novel demonstration of improvement in ISV with motivational contingencies for boys, but not girls, with ADHD and associations with PFC anatomy informs our understanding of sex differences and motivational factors contributing to ISV in children with ADHD.

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

“…based on DSM-IV criteria. Children taking psychotropic medications other than stimulants were excluded from participation and all children taking stimulants were asked to withhold their medication the day of and day prior to the laboratory visit, as in prior work including children on long-acting stimulants (Rosch et al, 2015; Rosch & Mostofsky, 2016; Seymour et al, 2016). Fifteen participants within the ADHD group (58%) were regularly taking a stimulant medication, 10 of which were taking long-acting formulations.…”

“…Another recent study from our laboratory expanded upon this work by including a large sample of boys and girls to address potential ADHD-related sex differences in the effect of motivational contingencies on cognitive task performance (Rosch, Dirlikov, & Mostofsky, 2015). This study showed that boys with ADHD showed similar improvements in response control with motivational contingencies as did control boys and girls, whereas girls with ADHD did not show this improvement (Rosch et al, 2015). …”

“…Furthermore, recent evidence suggests that girls and boys with ADHD differ in their degree of delay discounting and the extent to which motivational contingencies and cognitive load impact response control. Examination of the relationship between increased delay discounting and changes in response control with motivational contingencies (Rosch et al, 2015) and cognitive load (Seymour et al, 2016) may elucidate the cognitive and motivational processes underlying delay discounting in ADHD (Rosch & Mostofsky, 2016) and inform our understanding of ADHD-related sex differences.…”

“…We included participants from our previous studies who had completed multiple go/no-go (GNG) tasks (standard, complex, and motivational; Rosch et al, 2015; Seymour et al, 2016), as well as the real-time and classic delay discounting tasks (Rosch & Mostofsky, 2016) in order to examine whether and how the separate findings of (a) poorer response control with increased cognitive load (Seymour et al, 2016), (b) diminished benefits of motivational contingencies (Rosch et al, 2015), and (c) greater delay discounting in children with ADHD (Rosch & Mostofsky, 2016), are related. This study is novel in its integration of previous findings from our previous study examining delay discounting (Rosch & Mostofsky, 2016) with the same tasks included in the current study and several prior studies characterizing response control using the various go/no-go tasks examined here (Rosch et al, 2015; Seymour et al, 2016; Vaurio et al, 2009; Wodka et al, 2007) to improve our understanding how cognitive and motivational effects on response control relate to delay discounting in children with ADHD.…”

Increased Delay Discounting on a Novel Real-Time Task among Girls, but not Boys, with ADHD

“…Studies have also reported sex differences in neuropsychological functioning in children with ADHD (Hasson & Fine, 2012; O’Brien, Dowell, Mostofsky, Denckla, & Mahone, 2010; Seymour, Mostofsky, & Rosch, 2015; Wodka et al, 2008), with girls generally showing more deficits in planning and strategy mediated by prefrontal circuits, and boys showing greater impairments in more basic aspects of response control mediated by motor/ premotor circuits. Two recent studies revealed a sexually dimorphic effect of working memory demands (Seymour et al, 2015) and reinforcement (Rosch, Dirlikov, & Mostofsky, 2015) on response control. Specifically, girls with ADHD only displayed impaired response control under conditions of greater working memory demands, whereas response control was impaired among boys with ADHD regardless of working memory demands (Seymour et al, 2015).…”