Objective: Reward-processing abnormalities are thought to be a key feature of various psychiatric disorders and may also play a role in disruptive mood dysregulation disorder (DMDD), a new diagnosis in DSM-5. In the current study, we used event-related potentials (ERP) sensitive to monetary gains (i.e., the reward positivity [RewP]) and losses (i.e., the N200) to examine associations between symptoms of DMDD during early childhood and later reward processing during preadolescence.
Methods: To assess early emerging DMDD symptoms in a large longitudinal community sample (n=373) of 3-year old children, we administered a diagnostic interview, Preschool Age Psychiatric Assessment (PAPA) with parents. At a later assessment, ∼6 years later, children completed a monetary reward task while an electroencephalogram (EEG) was recorded. Children's lifetime history of psychopathology was also assessed at that time using Kiddie-Schedule of Affective Disorders and Schizophrenia (K-SADS) with the child and parent.
Results: Multiple regression analyses revealed that age 3 DMDD symptoms predicted an enhanced RewP to monetary rewards in preadolescence. This association is independent of demographics and lifetime history of symptoms of depression, any anxiety disorder, attention-deficit disorder, oppositional defiant disorder, or conduct disorder Conclusions: Early manifestations of DMDD in children as young as 3 years old predicted enhanced reward processing later in development. These findings add to the growing corpus of literature on the pathophysiology of DMDD, and underscore the predictive validity of preschool DMDD on a neural level.