Can binocular rivalry reveal neural correlates of consciousness?

Binocular rivalry, a phenomenon where perception alternates between two incompatible images presented to each eye, has been used to study the neural correlates of conscious vision. This essay critically examines four key questions about its usefulness: what comparison condition is appropriate, how to separate abolished awareness from inattention, whether findings from rivalry generalize to other perceptual phenomena, and whether neural activity linked to rivalry truly constitutes a neural correlate of consciousness. The authors arrive at skeptical answers to these questions but suggest that a more nuanced use of binocular rivalry can still provide insights into neural dynamics and components of consciousness, including those involved in perceptual decision-making.

Study at a glance

Abstract

This essay critically examines the extent to which binocular rivalry can provide important clues about the neural correlates of conscious visual perception. Our ideas are presented within the framework of four questions about the use of rivalry for this purpose: (i) what constitutes an adequate comparison condition for gauging rivalry's impact on awareness, (ii) how can one distinguish abolished awareness from inattention, (iii) when one obtains unequivocal evidence for a causal link between a fluctuating measure of neural activity and fluctuating perceptual states during rivalry, will it generalize to other stimulus conditions and perceptual phenomena and (iv) does such evidence necessarily indicate that this neural activity constitutes a neural correlate of consciousness? While arriving at sceptical answers to these four questions, the essay nonetheless offers some ideas about how a more nuanced utilization of binocular rivalry may still provide fundamental insights about neural dynamics, and glimpses of at least some of the ingredients comprising neural correlates of consciousness, including those involved in perceptual decision-making.