Conscious perception and perceptual echoes: a binocular rivalry study

Abstract Alpha rhythms (∼10Hz) in the human brain are classically associated with idling activities, being predominantly observed during quiet restfulness closed eyes. However, recent studies demonstrated that alpha can directly relate to visual stimulation, resulting oscillations, which last for as long one second. This reverberation, dubbed perceptual echoes (PE), suggests system actively samples and processes information within alpha-band frequency. Although PE have been linked various functions, their underlying mechanisms functional role not completely understood. In this study, we investigated relationship between conscious perception generation amplitude of PE. Specifically, displayed two coloured Gabor patches different orientations on opposite sides screen, using a set dichoptic mirrors, induced binocular rivalry stimuli. We asked participants continuously report they consciously perceived, while recording EEG signals. Importantly, luminance each patch fluctuated randomly over time, generating random sequences from estimated impulse-response functions (IRFs) reflecting generated by perceived (dominant) non-perceived (suppressed) stimulus, respectively. found power stimulus was comparable monocular vision (control condition) higher than suppressed stimulus. Moreover, confirming previous findings, all PEs propagated travelling wave posterior frontal regions, irrespective perception. All our results demonstrate correlation PE, suggesting synchronization neural activity plays an important sampling