Pubertal influences on neural activation during risky decision-making in youth with ADHD and disruptive behavior disorders

Abstract

Objective: Risk-taking during adolescence is a leading cause of mortality; Neuroscience research examining pubertal effects on decision-making is needed to better inform interventions, particularly among youth with attention-deficit/hyperactivity (ADHD) and disruptive behavior disorders (DBD), who are particularly prone to risky decision-making. We examined effects of pubertal development on risky decision-making and neural activation during decision-making among youth with ADHD/DBDs.

Method: Forty-six 11-12-year-olds (29.4% girls; 54.9% white; Tanner M(SD) = 2.08(1.32)) who met DSM-5 criteria for ADHD/DBD completed the Balloon Analog Risk Task (BART) during fMRI scanning. We examined effects of Tanner stage, sex, and age on risky decision-making (mean wager at which individuals stopped balloon inflation) and neural activation in the middle frontal gyrus and the ventral striatum during the choice and outcome phases of decision-making.

Results: Those in earlier pubertal stages made riskier decisions during the BART compared to those in later Tanner stages (β=-0.62, p = .02). Later pubertal stage was associated with greater activation in the left middle frontal gyrus (β=0.61, p = .03) during the choice phase and in the right ventral striatum in response to rewards (β=0.59, p = .03).

Conclusion: Youth with ADHD/DBD in later stages of puberty, regardless of age, show greater ventral striatal activation in response to rewards.

Keywords: ADHD; Decision-making; Disruptive behavior disorders; Neuroimaging; Puberty; fMRI.

Fig. 1

Illustration of the Balloon Analog Risk Task (BART). At the start of each trial, a balloon is displayed on the screen along with a green decision cue indicating a button can be pressed (a). Participants then choose to inflate the balloon (Choose Inflate) or take the accumulated wager (Choose Win, i.e., “cash out”) via button pressing (b). The time between decision and outcome phases of each trial is randomly jittered (0–6 seconds) to enable differentiation of decision-making and feedback-related processes. Following Choose Win trials, participants view a screen that says “You Win!” for 1000 ms followed by a fixation screen for 2–4 seconds before starting a new balloon trial (c). Following Choose Inflate trials, the balloon either explodes or inflates (d). For explosions, participants view an exploding balloon for 1500 ms (e) and then the fixation screen, while inflate trials show an inflated balloon for 1500 −2500 ms before permitting another choice (f). For each balloon, explosions are possible at any inflation choice except the first, with the likelihood of explosion increasing as the balloon size increases. A maximum of 12 inflations are possible for each balloon (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article).

Fig. 2

Significant Effects of Tanner and Sex on Activation during Choice and Outcome Trials. Regions of interest (left) are depicted for left middle frontal gyrus (MFG) and right ventral striatum. Scatterplots (right) depict mean ROI beta estimates for contrasts of interest showing a significant relationship with Tanner stage (VS) or a Tanner-by-Sex interaction (MFG).