Reward-Driven Brain Reconfiguration During Response Inhibition Relates to Motivation and Risk-Taking in Children

• In Event: Poster Session 13
  In Poster Session: PS 13 Topic - Biological Processes: Neuroscience and Genetics

Abstract

Inhibitory control is the ability to regulate our reactions and impulses and is improved with external rewards. During development, both control and reward processing abilities predict lifespan outcomes (i.e., substance use and mental health). Understanding the impact of reward on inhibitory control in children is critical to understanding self-regulation and risk-taking behaviors. Brain network interactions underlie both inhibitory control and reward processes, and thus offer a powerful approach to uncover the mechanisms by which these processes interact. We recently demonstrated that in children performing a response inhibition task, the addition of external rewards evoked reconfiguration of brain networks related to cognitive control and reward processing (Fig. 1a). However, the relevance of this reconfiguration to measures of motivation and risk-taking has yet to be explored.

To test this, typically developing children (N=24(10F), 8-12yrs, mean=10.4yrs) completed standard and rewarded versions of a task that probes response inhibition, the go/no-go task, during an fMRI scanning session. The rewarded go/no-go task was identical to the standard task but with monetary rewards for accuracy and speed. Children completed self-report questionnaires assessing motivation (BIS/BAS) and risk-taking (DOSPERT). Functional connectivity (FC) matrices were constructed for each task from the correlation between time courses of activity in pairs of brain regions. Reconfiguration was operationalized as the spatial similarity of the two FC matrices, calculated with Pearson’s correlations. Spatial similarity was calculated for the whole brain as well as specific brain networks implicated in cognitive control and reward processing. Linear regressions were conducted to assess the relationship between FC spatial similarity and measures of motivation and risk-taking. Age and sex were included as covariates.

We found that greater spatial similarity across the whole brain (p < .05; Fig. 1b), and specifically in the fronto-parietal (p < .01), cingulo-opercular (p < .05), default mode (p < .05), and salience networks (p < .01), was related to lower behavioral inhibition (BIS). Thus, greater reconfiguration of the whole brain, and particularly of cognitive control and default mode networks, when receiving external monetary rewards was related to greater behavioral inhibition, or motivation to avoid adverse outcomes. Conversely, we found that greater spatial similarity in the reward network (p < .05; Fig. 1c.) was related to greater behavioral activation (BAS drive), or goal-oriented motivation. This may indicate that individuals who were already internally motivated to perform well on the task were less motivated by external reward. Finally, we found that greater spatial similarity in the default mode network (p < .05; Fig. 1d) was related to greater risk-taking (DOSPERT). Altogether, during a response inhibition task more reward-driven brain reconfiguration was related to greater behavioral inhibition, as well as to less goal-oriented motivation and less risk-taking. Together, these findings indicate that individual differences in motivation and risk-taking impact the degree of modulation of brain systems by reward. Notably, neural impacts of reward were not constrained to reward processing-specific networks, but distributed across the brain. Tracking reward-driven brain reconfiguration across childhood and adolescence can improve our understanding of maturational trajectories of reward seeking and risk-taking behaviors.

Authors

• Mackenzie E Mitchell, University of North Carolina at Chapel Hill
  Presenting Author

• Nicholas Fogleman, University of Louisville
  Non-Presenting Author

• Jessica R Cohen, University of North Carolina at Chapel Hill
  Non-Presenting Author