# Traumatic brain injury, working memory-related neural processing, and alcohol experimentation behaviors in youth from the ABCD cohort

## TL;DR

This study explores how traumatic brain injury in adolescents affects their brain activity and likelihood of trying alcohol, finding that increased brain activity in certain regions may protect against early alcohol use.

## Contribution

The study identifies a protective neural mechanism in TBI-affected youth against early alcohol experimentation.

## Key findings

- Neural activity in the fronto-basal ganglia network predicted increased odds of alcohol sipping in adolescents.
- Increased left frontal pole activity was uniquely protective against alcohol sipping in TBI-affected youth.
- The protective effect was not observed in youth without TBI.

## Abstract

Adolescent traumatic brain injury (TBI) has long-term effects on brain functioning and behavior, impacting neural activity under cognitive load, especially in the reward network. Adolescent TBI is also linked to risk-taking behaviors including alcohol misuse. It remains unclear how TBI and neural functioning interact to predict alcohol experimentation during adolescence. Using Adolescent Brain Cognitive Development (ABCD) study data, this project examined if TBI at ages 9–10 predicts increased odds of alcohol sipping at ages 11–13 and if this association is moderated by neural activity during the Emotional EN-Back working memory task at ages 11–13. Logistic regression analyses showed that neural activity in regions of the fronto-basal ganglia network predicted increased odds of sipping alcohol by ages 11–13 (p < .05). TBI and left frontal pole activity interacted to predict alcohol sipping (OR = 0.507, 95% CI [0.303 - 0.846], p = .009) – increased activity predicted decreased odds of alcohol sipping for those with a TBI (OR = 0.516, 95% CI [0.314 - 0.850], p = .009), but not for those without (OR = 0.971, 95% CI [0.931 −1.012], p = .159). These findings suggest that for youth with a TBI, increased BOLD activity in the frontal pole, underlying working memory, may be uniquely protective against the early initiation of alcohol experimentation. Future work will examine TBI and alcohol misuse in the ABCD cohort across more time points and the impact of personality traits such as impulsivity on these associations.