Stimulant medication and development of the dopamine system in ADHD: a pharmacological MRI study

Motivation: The effects of stimulant treatment (e.g. methylphenidate) on the brain’s dopamine system remain unclear. While animal studies and short-term human trials suggest potential lasting impacts, a comprehensive understanding is lacking. Goal(s): This study aimed to investigate the persistent effects of stimulant treatment on the dopamine system. Approach: Using data from a naturalistic follow-up of an ADHD trial, we examined the cerebral blood flow (CBF) response to methylphenidate as a proxy for dopamine function. Results: Our findings reveal age-dependent effects. Specifically, we observed a negative association between medication use and CBF response in adolescents, while such an association was absent in adults. Impact: We found an association between patterns of stimulant treatment for ADHD and the cerebral blood flow response to a dopamine-challenge in adolescents, but not adults. This suggests potential for personalization of stimulant treatment approaches for adolescents with ADHD.