Feedback-Based Learning of Timing in Attention-Deficit/Hyperactivity Disorder and Neurofibromatosis Type 1

Abstract

Objective: Patients with Neurofibromatosis Type 1 (NF1) frequently display symptoms resembling those of Attention Deficit/Hyperactivity Disorder (ADHD). Importantly, these disorders are characterised by distinct changes in the dopaminergic system, which plays an important role in timing performance and feedback-based adjustments in timing performance. In a transdiagnostic approach, we examine how far NF1 and ADHD show distinct or comparable profiles of timing performance and feedback-based adjustments in timing. Method: We examined time estimation and learning processes in healthy control children (HC), children with ADHD with predominantly inattentive symptoms and those with NF1 using a feedback-based time estimation paradigm. Results: Healthy controls consistently responded closer to the correct time window than both patient groups, were less variable in their reaction times and displayed intact learning-based adjustments across time. The patient groups did not differ from each other regarding the number of in-time responses. In ADHD patients, the performance was rather unstable across time. No performance changes could be observed in patients with NF1 across the entire task. Conclusions: Children with ADHD and NF1 differ in feedback learning-based adjustments of time estimation processes. ADHD is characterised by behavioural fluctuations during the learning process. These are likely to be associated with inefficiencies in the dopaminergic system. NF1 is characterised by impairments of feedback learning which could be due to various neurotransmitter alterations occurring in addition to deficits in dopamine synthesis. Results show that despite the strong overlap in clinical phenotype and neuropsychological deficits between NF1 and ADHD, the underlying cognitive mechanisms are different.

Differential Attention Functioning in Pediatric Chronic Kidney Disease

“…For example, less disease severity related to better functioning in the Focus/Execute, Sustain, and Encode attention dimensions, while shorter disease duration related to higher scores on the Encode dimension. Identifying attention problems, in a more detailed fashion, may subsequently impact a child's life course by guiding more specific types of educational and/or behavioral interventions (Groothoff, 2005), and future studies should examine whether this attention profile is similar to attention dimensions in other pediatric disorders (e.g., Neurofibromatosis Type I) (Prochnow et al, 2022).…”

Assessing Psychiatric Comorbidity and Pharmacologic Treatment Patterns Among Patients With Neurofibromatosis Type 1

“…The presence of psychiatric comorbidities in patients with NF1 is likely due in part to the high burden of disease [24], particularly related to skin lesions [25], but may also have a neurobiological basis that is not currently understood [26]. For example, learning deficits in patients with NF1 appear to arise from a different mechanism than ADHD in patients without NF1 [27,28]. The activity of specific neurotransmitter pathways may be implicated.…”