# Negative Urgency Mediates the Effect of Family Conflict on Cannabis Positive Expectancy: The Moderating Role of Anterior Cingulate Cortex

## TL;DR

Family conflict increases teens' positive beliefs about cannabis use through stress-driven impulsivity, with brain activity amplifying this effect.

## Contribution

This study identifies a neural mechanism (ACC activation) that moderates how stress-related impulsivity links family conflict to cannabis expectancies.

## Key findings

- Family conflict increases cannabis positive expectancies via elevated negative urgency in adolescents.
- ACC activation during emotional reward processing intensifies the impact of negative urgency on cannabis expectancies.
- Left and right caudal and rostral ACC regions show significant moderation effects on the indirect pathway.

## Abstract

Cannabis positive expectancies, favourable beliefs about cannabis effects, are a key risk factor for cannabis initiation and problematic use during adolescence. Prior research demonstrated a robust association between cannabis positive expectancies and increased use among adolescents, yet less is known about the developmental aetiology, biobehavioural mechanisms and cognitive context that contribute to these expectancies. The present study examines the intermediary role of negative urgency, a facet of impulsivity characterized by rash action under distress. Additionally, the study investigates whether anterior cingulate cortex (ACC) activation during emotional reward processing moderates this indirect effect. We conducted a longitudinal moderated mediation model with three waves of data from the Adolescent Brain and Cognitive Development (ABCD) study, analysing 6638 youths (baseline Mage = 10.1 years; 47.8% female). Family conflict at baseline predicted increased cannabis positive expectancies ΔT5T7 through increases in negative urgency at T5 (β = 0.017, p < 0.001, 95% CI [0.045, 0.069]). Heightened ACC activity at T5 (anticipatory large loss), including bilateral caudal and rostral regions, intensified negative urgency's impact on cannabis positive expectancy ΔT5T7: Left caudal (β = 0.081, p < 0.001, 95% CI [0.041, 0.122]), right caudal (β = 0.062, p = 0.004, 95% CI [0.020, 0.105]), right rostral (β = 0.041, p = 0.026, 95% CI [0.001, 0.081]) and left rostral (β = 0.052, p = 0.01, 95% CI [0.012, 0.092]). This study highlights how neural activity amplifies stress‐related effects on adolescent substance use expectations, suggesting emotional decision‐making as a target for prevention.

Family conflict was associated with higher cannabis‐positive expectancies indirectly through elevated negative urgency in youth. ACC activation during anticipatory large loss (rostral and caudal) amplified this indirect pathway, indicating that heightened ACC responsivity under distress strengthens emotion‐driven impulsivity and related expectancies.