Rewards transiently and automatically enhance sustained attention.

Our ability to maintain a consistent attentional state is essential to many aspects of daily life. Still, despite our best efforts, attention naturally fluctuates between more and less vigilant states. Previous work has shown that offering performance-based rewards or incentives can help to buffer against attentional lapses. However, such work is generally focused on long timescales and, critically, does not dissociate between task-based motivation (i.e., where reward is contingent on attention performance) versus more generic motivation or arousal accounts of reward effects. Here, we investigated the influence of reward feedback on attentional vigilance during a simultaneous sustained attention and reinforcement learning (RL) task. Crucially, rewards were tied only to the RL task rather than to attentional performance. We assessed the impact of two core components of RL-reward and surprise-on short-term fluctuations in attentional vigilance. In two experiments (N = 161), we demonstrated that intermittent, attention-independent rewards transiently boosted vigilance on a timescale of seconds. We did not find consistent evidence that surprises modulated vigilance. In a third experiment (N = 135), we observed that even passively received rewards elicit transient boosts in sustained attention. Together, these findings suggest that rewards transiently buffer against attentional lapses to improve vigilance, likely through generic increases in arousal or motivation. These results point to a fundamental relationship between reward and sustained attention. (PsycInfo Database Record (c) 2025 APA, all rights reserved).