SPATIOTEMPORAL BRAIN DYNAMICS OF INHIBITORY CONTROL IN ADOLESCENTS AND YOUNG ADULTS

Inhibitory control, the ability to inhibit impulsive responses in favor of voluntary responses, remains immature during adolescence. Although this behavior has been well documented, the cognitive and neural processes associated with immature inhibitory control during adolescence are still not well understood. To address this question, we collected Magnetoencephalography (MEG) data from 17 adolescents (age 14-16) and 20 adult participants (age 20-30), where participants performed the antisaccade (AS) and control prosaccade (PS) tasks. Leveraging MEG’s high temporal resolution, our goal was to delineate developmental changes in local neural oscillations and inter-regional neural synchronization associated with preparatory inhibitory control. Participants were shown a preparatory cue (a red “x” for AS or a green “x” for PS) for 1500 ms, followed by a peripheral target where participants were instructed to make a saccade toward (PS) or away (AS) from the target. Neural activity estimates from a priori brain regions were then extracted for oscillatory power and phase synchrony analyses. We found that compared to adults, adolescents showed decreased alpha-band power in the oculomotor regions in preparation to inhibit an upcoming reflexive saccade, suggesting immaturities in functional inhibition of task-inappropriate activity. Furthermore, adolescents showed weaker beta-band power in prefrontal cognitive control regions, which could reflect less robust top-down biasing of sensory and motor processes. Lastly, we found that adolescents showed decreased levels of phase synchrony between frontal and parietal regions, possibly reflecting immaturities in iv\ud coordinating distributed cortical activities. Our results suggest that immaturities in functional inhibition, top-down control, and inter-regional synchrony collectively contribute to immature inhibitory control during adolescence