  Predictive coding theory suggests that conscious perception results from the
interaction between top-down and bottom-up signals in the brain. However, the
electrophysiological signatures of top-down predictions are not clear yet.
Here, we cued subjects to expect a certain perceptual state in a binocular
rivalry task and quantitatively analyzed their EEG signals during the cue
period and prior to binocular rivalry task. We found that when predictions can
successfully influence the perception of the rivalrous stimuli, the power of
beta band rhythms increases in primary visual cortices and beta band phase lag
in a frontal-visual homologous channel pair was notably diminished. Building
upon earlier works, our findings suggest that beta rhythm is potentially
considered as a signature of top-down communication in the brain.
