Low frequency oscillatory bursts in the macaque prefrontal cortex predict spontaneous transitions in the content of consciousness

In multistable perception, the content of consciousness alternates spontaneously between mutually exclusive or mixed interpretations of competing representations. Identifying neural signals predictive of such intrinsically driven perceptual transitions is fundamental in resolving the mechanism and localizing the brain areas giving rise to visual consciousness. Here we employed a no-report paradigm of binocular motion rivalry based on the optokinetic nystagmus reflex read-out of spontaneous perceptual transitions coupled with multielectrode recordings of local field potentials and single neuron discharges in the macaque prefrontal cortex. We show that an increase of oscillatory bursts in the delta-theta (1-9 Hz), and a decrease in the beta (20-40 Hz) bands, along with significant perceptual modulation of single neurons during periods of dominance and perceptual switches, are predictive of spontaneous transitions in the content of visual consciousness. These results suggest that the balance of stochastic prefrontal fluctuations is critical in refreshing conscious perception, casting doubt on a posterior cortical mechanism for visual awareness