The neurodevelopment of value-driven attention

Reward plays an essential role in prioritizing the processing of sensory information. Past psychological
studies in human adults have shown that rewarding stimuli not only facilitate goal-directed behaviors but
also cause distraction when they are irrelevant to the current behavioral task. While neural mechanisms
underlying value-driven attention have been increasingly well understood, it is still unclear how the
human brain develops to support value-driven attention. To address this question, we measured EEG from
typically developing adolescents and healthy adults performing a variant of value-driven attention tasks
where we assessed the impacts of low and high reward values associated with the colors of task-irrelevant visual stimuli (i.e., low- and high-valued distractors) on the behavioral performance at discriminating task-
relevant targets as well as the amplitude of the N2pc, the well-known event-related potential (ERP) index of covert visual attention related to target selection. Consistent with previous reports, in adults, low-
valued distractors did not change behavioral performance at discriminating task-relevant targets and did not modulate the amplitude of target-related N2pc. On the other hand, high-valued distractors led to worse discrimination performance and the reduction in the N2pc amplitude compared to the low-valued- distractor and no-distractor conditions. In contrast, teenagers exhibit different patterns of reward modulations at both behavioral and neural levels. While high-valued distractors increased behavioral inference and reduced the N2pc amplitude in a similar degree as the adult group, low-valued distractors produced much higher attentional capture effects in teenagers compared to adults. These resulted in comparable levels of attentional capture effects between low- and high-valued distractors in the younger group. Together, our findings suggest that the differential effects that low and high rewards have upon attention in adulthood are caused by the reduced sensitivity of the attentional system to visual stimuli associated with low reward values during development.