Abstract
Reward plays a critical role in motivating overt, goal-directed behavior, and can also shape patterns of visual attention, with reward-related stimuli receiving automatic prioritization. In the current study, we demonstrate an ‘earlier’ effect of reward on visual perception, wherein the rewards signaled by visual stimuli modulate perceptual encoding and conscious experience of those stimuli. Our study used a visual masking procedure that required perceptual encoding, retention, and retrieval of a masked grating (memory cue). Experiment 1 showed that response accuracy was greater when a briefly presented (17 ms) and masked grating signaled that a high reward was available than when it signaled a low reward. Reward enhanced perceptual encoding/retention when participants reported awareness of the memory cue; notably, performance was also significantly above chance for high-reward (but not low-reward) gratings when participants reported being fully unaware of the memory cue. Experiment 2 demonstrated that this reward-driven enhancement was not a consequence of greater motivation to retrieve the memory cue on high-reward trials: when information about reward availability was provided at retrieval (rather than encoding), no advantage was observed for high-reward trials. These findings suggest that reward exerts an early and rapid influence to improve the fidelity of visual perception through strengthening information encoding and retention.