Attentional Rhythms Are Sensitive to Binocular Visual Pathway.

Visual attention is intrinsically rhythmic and oscillates based on the discrete sampling of either single or multiple objects. Recently, studies have found that the early visual cortex (V1/V2) modulates attentional rhythms. Both monocular and binocular cells are present in the early visual cortex, which acts as a transfer station for transformation of the monocular visual pathway into the binocular visual pathway. However, whether the neural site of attentional rhythms is in the monocular or binocular visual pathway needs further study. In the current study, we leveraged the anatomical features of the monocular and binocular pathway to design a paradigm with same-eye and different-eye presentations of cues and targets. By combining this approach with EEG recordings and analysis the impulse response function (TRF), we aimed to address this question. In Experiment 1, we reset the phase of attentional rhythms in one monocular channel (left eye or right eye) by a dichoptic cue and tracked the impulse response function (TRF) of the monocular channel in the left and right eye separately. We found no significant differences in the respective TRFs and their spectra for each eye, suggesting that attention rarely switched between the two eyes, indicating that the binocular visual pathway, not the monocular visual pathway, is the neural site of attentional rhythms. These results were verified when resetting the phases of attentional rhythms by a binocular cue in Experiment 2. These results suggest that attentional rhythms may be sensitive to activities in the binocular visual pathway.