Abstract
In multistable visual 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 identifying the brain areas giving rise to visual consciousness. In a previous study, using a no-report paradigm of externally induced perceptual suppression, we have shown that functionally segregated neural populations in the macaque prefrontal cortex explicitly reflect the content of consciousness and encode task phase. Here I will present results from a no-report paradigm of binocular motion rivalry based on the optokinetic nystagmus (OKN) reflex read-out of spontaneous perceptual transitions coupled with multielectrode recordings of local field potentials and single neuron discharges in the macaque prefrontal cortex. An increase in the rate of oscillatory bursts in the delta-theta (1–9 Hz), and a decrease in the beta (20–40 Hz) bands, were predictive of spontaneous transitions in the content of visual consciousness that was also reliably reflected in single neuron discharges. Mapping these perceptually modulated neurons revealed stripes of competing populations, also observed in the absence of OKN. These results suggest that the balance of stochastic prefrontal fluctuations is critical in refreshing conscious perception, and pre-frontal neural populations reflect the content of consciousness. Crucially, consciousness in the prefrontal cortex could be observed for faces and complex objects but also for low-level stimulus properties like direction of motion therefore suggesting a reconsideration of the view that prefrontal cortex is not critical for consciousness.