Prominent theoretical accounts of attention-deficit/hyperactivity-disorder (ADHD) hypothesize that reinforcement learning deficits underlie symptoms of ADHD. The Dynamic Developmental Theory and the ...Dopamine Transfer Deficit hypothesis assume impairments in both the acquisition and extinction of behavior, especially when learning occurs under partial (non-continuous) reinforcement, and subsequently the Partial Reinforcement Extinction Effect (PREE). Few studies have evaluated instrumental learning in ADHD and the results are inconsistent. The current study investigates instrumental learning under partial and continuous reinforcement schedules and subsequent behavioral persistence when reinforcement is withheld (extinction) in children with and without ADHD.
Large well-defined samples of children with ADHD (n = 93) and typically developing (TD) children (n = 73) completed a simple instrumental learning task. The children completed acquisition under continuous (100%) or partial (20%) reinforcement, followed by a 4-min extinction phase. Two-way (diagnosis by condition) ANOVAs evaluated responses needed to reach the learning criterion during acquisition, and target and total responses during extinction.
Children with ADHD required more trials to reach criterion compared to TD children under both continuous and partial reinforcement. After partial reinforcement, children with ADHD executed fewer target responses during extinction than TD children. Children with ADHD executed more responses than TD children during extinction, irrespective of learning condition.
The findings demonstrate general difficulties in instrumental learning in ADHD, that is, slower learning irrespective of reinforcement schedule. They also show faster extinction following learning under partial reinforcement in those with ADHD, that is, a diminished PREE. Children with ADHD executed more responses during extinction. Results are theoretically important, with clinical implications for understanding and managing learning difficulties in those with ADHD, as they suggest poorer reinforcement learning and lower behavioral persistence.
Although instrumental learning deficits are, among other deficits, assumed to contribute to attention-deficit/hyperactivity disorder (ADHD), no comprehensive systematic review of instrumental ...learning deficits in ADHD exists. This review examines differences between ADHD and typically developing (TD) children in basic instrumental learning and the effects of reinforcement form, magnitude, schedule, and complexity, as well as effects of medication, on instrumental learning in children with ADHD.
A systematic search of PubMed, PsyINFO, CINAHL, EMBASE+EMBASE CLASSIC, ERIC, and Web of Science was conducted for articles up to March 16, 2020. Experimental studies comparing instrumental learning between groups (ADHD versus TD) or a manipulation of reinforcement/medication within an ADHD sample were included. Quality of studies was assessed with an adapted version of the Hombrados and Waddington criteria to assess risk of bias in (quasi-) experimental studies.
A total of 19 studies from among 3,384 non-duplicate screened articles were included. No difference in basic instrumental learning was found between children with ADHD and TD children, nor effects of form or magnitude of reinforcement. Results regarding reinforcement schedule and reversal learning were mixed, but children with ADHD seemed to show deficits in conditional discrimination learning compared to TD children. Methylphenidate improved instrumental learning in children with ADHD. Quality assessment showed poor quality of studies with respect to sample sizes and outcome and missing data reporting.
The review identified very few and highly heterogenous studies, with inconsistent findings. No clear deficit was found in instrumental learning under laboratory conditions. Children with ADHD do show deficits in complex forms of learning, that is, conditional discrimination learning. Clearly more research is needed, using more similar task designs and manipulations.
Few studies have assessed parent–adolescent conflict in adolescents with ADHD, potential related factors to this conflict and parent–adolescent agreement on their conflicts. This study compared ...parent–adolescent conflict in a large sample of adolescents with ADHD/ODD, ADHD only and a sample of typically developing TD adolescents. Further, informant discrepancies between parents and adolescents regarding conflict and factors (ODD, planning problems, depression and anxiety) relating to this parent–adolescent conflict were investigated. Adolescents (50 ADHD/ODD, 109 ADHD, 34 TD) aged 12 to 17 years old and their parents completed questionnaires on parent–adolescent conflict, ADHD symptoms, ODD symptoms, planning problems, depression and anxiety symptoms. Significant differences in conflict between all groups were found; the ADHD/ODD group showed most parent–adolescent conflict and the TD group the least. In the total ADHD sample (ADHD only combined with ADHD/ODD adolescents), no informant discrepancies between parents and adolescents were found on conflict measures. Within the total ADHD sample, parent–adolescent conflict was related to parent-reported ODD symptoms and planning problems. Parent–adolescent conflict is pronounced in adolescents with ADHD and even more in adolescents with ADHD/ODD. Parents and adolescents agree on the frequency of conflict. ODD symptoms and planning problems are related factors to conflict and could be important aims for treatment in adolescents with ADHD.
Highlights
Adolescents with ADHD show heightened frequency of parent–adolescent conflict.
Comorbid ODD heightens this conflict in adolescents with ADHD even more.
Parents and adolescents agree on how frequent they have conflicts.
Planning problems and ODD symptoms predict frequency of parent–adolescent conflict.
PDF
