Instrumental learning and behavioral persistence in children with attention-deficit/hyperactivity-disorder: does reinforcement frequency matter?

BACKGROUND: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Systematic Review: Attention-Deficit/Hyperactivity Disorder and Instrumental Learning.

OBJECTIVE: 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. METHOD: 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. RESULTS: 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. CONCLUSION: 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.

Measuring child and adolescent emotional lability: How do questionnaire-based ratings relate to experienced and observed emotion in everyday life and experimental settings?

OBJECTIVES: Emotional lability (EL) is an important trans-diagnostic concept that is associated with significant functional impairment in childhood and adolescence. EL is typically measured with questionnaires, although little is known about the ecological validity of these ratings. In this paper, we undertook 2 studies addressing this issue by examining the relationship between rating-based measures of EL and directly measured emotional expressions and experiences. Furthermore, the associations between directly measured emotional expressions and experiences and attention-deficit/hyperactivity disorder (ADHD) symptomatology were also examined, given the clear association of EL with ADHD in former research. METHODS: In Study 1, we examined the relationship between parental report of children's EL and ADHD, and children's emotional expressions in an experimental context (N = 67). In Study 2, we examined the relationship between parental ratings and real-time measures of emotional experiences in daily life in adolescents (N = 65). RESULTS: EL ratings were associated with different elements of real-time emotional experiences and expressions. Elements of emotional expressions but not emotional experiences were also associated with ADHD symptom reports. CONCLUSIONS: These studies provide evidence for the ecological validity of EL ratings. Furthermore, they add evidence for the associations between EL and ADHD.

Child and parental executive functioning in type 1 diabetes: Their unique and interactive role toward treatment adherence and glycemic control.

OBJECTIVE: Managing type 1 diabetes (T1D) requires the ability to make complex and critical decisions regarding treatment, to execute complex tasks accurately, and to make adjustments when problems arise. This requires effective neuropsychological competences of patients and their families, especially in the domain of executive functioning (EF): the ability to self-monitor, plan, solve problems, and set priorities. Previous research focused mainly on child EF, neglecting the impact of parental EF. This study included both mothers and fathers and examined associations between child and parental EF and treatment adherence to T1D in a broad age range of patients. METHODS: Parents of 270 patients (6-18 years) with T1D (mean age 12.7 years; 52.6% female) were included. Mothers (N = 232) and fathers (N = 168) completed questionnaires on child and parental EF and on treatment adherence. Analyses examined the associations linking child and parental EF to treatment adherence and glycemic control (and potential moderation effects in these associations) using hierarchical linear regression. RESULTS: Child EF problems were negatively associated with treatment adherence. As an indication of moderation, this effect was stronger in older children. Better treatment adherence and glycemic control were reported when both child and parent showed less EF problems. Effects were more pronounced in mothers than in fathers. CONCLUSIONS: This study demonstrated a significant interplay between child and parental EF in the association with treatment adherence and glycemic control. Researchers and clinicians should remain attentive toward the role of neuropsychological concepts such as EF. Implementation in clinical practice seems meaningful.

A rating measure of ADHD-related neuropsychological impairment in children and adolescents: Data from the Cognition and Motivation in Everyday Life (CAMEL) Scale from population and clinical samples.

A new parent-completed questionnaire, the Cognition and Motivation in Everyday Life (CAMEL) scale, was developed to provide a comprehensive assessment of neuropsychological impairment in children related to attention-deficit/hyperactivity disorder (ADHD) across diverse cognitive, motivational and energetic domains. Its psychometric properties were investigated. A total of 60 items were generated to cover a wide range of putative ADHD-related neuropsychological processes. A clinical (n = 142) and community (n = 810) sample of parents with children between 6 and 16 years of age completed the questionnaire. Data on ADHD symptoms were also collected with a commonly-used, validated parent rating scale to explore the associations between CAMEL scores and dimensional measures of child ADHD and conduct problems. Factor analysis identified six factors which we labeled (i) Cognition, (ii) Self-Direction and Organization, (iii) Effort Engagement, (iv) Arousal Regulation, (v) Motivational Responsiveness, and (vi) Cautiousness. Self-Direction and Organization and Arousal Regulation were the strongest predictors for ADHD symptomatology. Self-Direction and Organization was strongly associated with inattention and Arousal Regulation with hyperactivity-impulsivity symptoms. Parents distinguished between broad neuropsychological domains in reliable and plausible ways, making distinctions between key aspects of functioning. However, the boundaries between these domains did not map directly onto the distinctions drawn within traditional models of ADHD deficits. Further research is required to examine the predictive validity and cost-effectiveness of the CAMEL scale compared to direct objective testing using laboratory measures in predicting prognosis and treatment outcome.