Parental substance use history density and its influence on reward anticipation brain activation in late childhood and early adolescence.

Parental history of problematic substance use (PH) increases the risk for early adolescent substance use (SU), potentially due to premorbid differences in reward-processing brain regions (e.g., striatum). However, no studies have prospectively examined the separate contributions of parental history of alcohol (PHA) and drug (PHD) use or the impact of PH density (PH, PH, PH) on reward processing in preadolescents. This study analyzed data from 10,235 participants (ages 9-14) in the Adolescent Brain Cognitive Development Study (ABCD). Reward processing was assessed using the Monetary Incentive Delay Task (MID) at baseline and two-year follow-up. Regions of interest included bilateral striatal activation elicited by neutral vs. anticipation of large rewards. Linear mixed-effect models evaluated PH, PHA, PHD, and PH density on ROI activation, controlling for relevant covariates. Results showed that youth with PHA had greater nucleus accumbens activation during reward anticipation than those with no history (PHA), but no significant differences were found between PHA and PHA or PHA and PHA. PHD and PH were not significantly associated with BOLD activation in striatal regions, nor were there changes over time. These findings highlight the need to consider both PH and environmental factors when assessing neurodevelopmental risk for early substance use.