Visual attention is intrinsically rhythmic and oscillates based on the discrete sampling of either single or multiple objects. Recently, studies employing transcranial magnetic stimulation (TMS) and high-temporal behavioral approaches have found that the early visual cortex (V1/V2) modulates attentional rhythms. However, both monocular cells and binocular cells are in the early visual cortex, and whether the neural site of attentional rhythms is monocular cells or binocular cells remains poorly understood. In Experiment 1, we reset the phase of attentional rhythms in one monocular channel (left eye or right eye) by the dichoptic cue and tracked the temporal response function (TRF) of the monocular channel in the left and right eyes separately using time response tracking technology. We found no significant differences in the two TRFs of each monocular eye, suggesting that attention rarely switched between the two eyes, indicating that binocular cells, not monocular cells, are the neural site of attentional rhythms. These results were verified even when resetting the phases of attentional rhythms by a binocular cue in Experiment 2. These results constitute direct neural evidence supporting rhythmic attention theory.
