Gender differentiated emotion-related neural predictors of growth in adolescent substance use

• In Event: Substance Use Risk in Adolescence: The Role of Emotion Processes and Family Variables

Abstract

Rates of substance use (SU) increase from early to middle adolescence (Johnston et al., 2021). Adolescent SU has negative consequences, including increasing risk for SU disorders in adulthood (Chassin et al., 2002). SU is increasing among adolescent girls, however pathways to SU for girls and gender differences in risk factors are understudied (Amaro et al., 2001). Altered neural responses to negative emotional and rewarding stimuli have been linked to SU in adults and may be risk factors for SU in adolescence. However, few studies have tested this. The present study examined neural responses to negative emotional and rewarding stimuli in early adolescence predicting increases in SU over a 3 year longitudinal follow up. Given theories of gender differences in predictors of SU (Hammerslag & Gulley, 2016), we examined gender differences in these associations.
Eighty one adolescents (42 boys; 70% White; age 12-14 at baseline) completed an MRI session at baseline, including a negative emotion processing fMRI task (viewing negative emotional and neutral images from the IAPS) and a monetary reward fMRI task (playing a card game and winning money or not winning money [neutral]). fMRI responses were extracted in the amygdala to negative emotional images (minus neutral images) and in nucleus accumbens [NAc] and ventromedial prefrontal cortex [vmPFC] to monetary reward (minus neutral). Adolescents reported on lifetime SU on the YRBS at baseline, and 1, 2, and 3 year follow-ups. Models examined growth in SU over the three year follow-ups for yes/no SU and then, for users, SU amount (YRBS frequency score).
Hierarchical Linear Models (HLMs) found R amygdala response to negative emotion X gender interactions predicting increases in SU amount from baseline through three year follow-up (b = -0.06, SE = 0.02, p = .01). For girls, higher R amygdala response predicted SU increases and for boys R amygdala did not predict SU increases (see Figure). HLMs found L NAc and R & L vmPFC response X gender interactions predicting increases in SU amount to three year follow up (for L NAc, b = -0.03, SE = 0.01, p = .02; for L vmPFC, b= -0.03, SE = 0.01, p = .02; for R vmPFC, b= -0.04, SE = 0.01, p = .05). For boys, lower NAc and vmPFC response to monetary reward predicted SU increases and for girls NAc and vmPFC responses did not predict SU increases (see Figure).
Findings suggest that high negative emotional reactivity may be a risk factor for SU for girls. High negative reactivity may lead girls to use substances to down-regulate negative emotions, consistent with self-medication theories of SU. Boys, in contrast, may take a pathway to SU characterized by blunted response to reward. Boys who lack response to rewards may use substances to up-regulate feelings of reward, consistent with sensation-seeking theories of SU. If replicated in larger samples, these findings suggest that it is important to develop gender-sensitive SU prevention programs. For example, preventions may focus more on negative emotion regulation for girls and more on increasing rewarding feelings for boys.

Authors

• Tara M Chaplin, George Mason University
  Presenting Author

• Stefanie Gonçalves

• James Thompson, George Mason University

• Timothy W Curby, George Mason University