Reward makes the rhythmic sampling of spatial attention emerge earlier

A growing body of evidence demonstrates a rhythmic characteristic spatial attention, with the corresponding behavioral performance fluctuating periodically. Here, we investigate whether and how attention is affected by reward—an important factor in attentional selection. We adopted classic cueing paradigm time-resolved stimulus-onset-asynchrony (SOA) between cue target such that responses to different phases could be examined. The color was associated either high or low level reward. Results showed low-frequency band (<2 Hz) where exogenous effects (i.e., facilitation inhibition return; IOR) appeared, reward enhanced late IOR effect through facilitating at uncued location. Recurring lower alpha power (alpha inhibition) which fluctuated low-theta frequency (2–3 observed cued location relative location, irrespective cue. Importantly, recurring emerged earlier (~120 ms) high-reward condition low-reward condition. propose implies sampling expectation makes periodic emerge earlier.