Neural activation during risky decision-making in youth at high risk for substance use disorders

Abstract

Risky decision-making, particularly in the context of reward-seeking behavior, is strongly associated with the presence of substance use disorders (SUDs). However, there has been little research on the neural substrates underlying reward-related decision-making in drug-naïve youth who are at elevated risk for SUDs. Participants comprised 23 high-risk (HR) youth with a well-established SUD risk phenotype and 27 low-risk healthy comparison (HC) youth, aged 10-14. Participants completed the balloon analog risk task (BART), a task designed to examine risky decision-making, during functional magnetic resonance imaging. The HR group had faster reaction times, but otherwise showed no behavioral differences from the HC group. HR youth experienced greater activation when processing outcome, as the chances of balloon explosion increased, relative to HC youth, in ventromedial prefrontal cortex (vmPFC). As explosion probability increased, group-by-condition interactions in the ventral striatum/anterior cingulate and the anterior insula showed increasing activation in HR youth, specifically on trials when explosions occurred. Thus, atypical activation increased with increasing risk of negative outcome (i.e., balloon explosion) in a cortico-striatal network in the HR group. These findings identify candidate neurobiological markers of addiction risk in youth at high familial and phenotypic risk for SUDs.

Keywords: Addiction risk; Adolescent; Decision-making; Functional imaging; Prefrontal cortex; Risk.

Conflict of interest statement

Conflicts of interest

The authors have no conflicts to declare.

Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Figures

Fig. 1

A schematic of the Balloon Analog Risk Task (BART) showing successive balloon inflations (i.e., a series of Choose Inflates) that either end in Outcome Inflate (“You Win!”) or an Outcome Explode (“You Lose!”).

Fig. 2

Group differences (healthy comparisons (HC) vs. high risk (HR)) on the parametrically modulated outcome contrast. Group differences, driven by increasing activation intensities as explosion probability increases in the HR group, were found in a bilateral cluster in the ventromedial prefrontal cortex (vmPFC; Table 5). Bar graphs plot activation intensities (y-axis) from the cluster according to condition (Outcome Inflate or Outcome Explode) and group (HC or HR). Line graphs illustrate the relationship between probabilities of balloon explosion (x-axis) vs. activation intensities of the blood oxygen level dependent (BOLD) signal in the cluster (y-axis).

Fig. 3

Group × Condition interactions, on the parametrically modulated outcome contrast. Outcome Interactions were found in: 1. Right ventral striatum and anterior cingulate cortex (ACC) and 2. Right anterior insula (AI)/inferior frontal gyrus (IFG; Table 5). In both clusters, high risk youth had increasing activation on the explosion trials. Asterisks indicate group differences (p<0.01). Bar graphs plot activation intensities (y-axis) from each cluster according to condition (Outcome Inflate or Outcome Explode) and group (healthy comparison (HC) vs. high risk (HR)). Line graphs illustrate the relationship between probability of balloon explosion (x-axis) vs. activation intensities of the blood oxygen level dependent (BOLD) signal for each cluster (y-axis).