Introduction to Research Topic – Binocular Rivalry: A Gateway to Studying Consciousness

Abstract

In 1593, Neapolitan polymath Giambattista della Porta publicly \nlamented that he was unable to improve his impressive productivity \n(he had published in areas as diverse as cryptography, \nhydraulics, pharmacology, optics, and classic fiction). Della \nPorta was trying to read two books simultaneously by placing \nboth volumes side-by-side, and using each eye independently. To \nhis great surprise, his setup allowed him to only read one book at \na time. This discovery arguably marks the first written account \nof binocular rivalry (Wade, 2000) – a perceptual phenomenon \nthat more than 400 years later still both serves to intrigue as \nwell as to illuminate the limits of scientific knowledge. At first \nglance, binocular rivalry is an oddball. In every day vision, our \neyes receive largely matching views of the world. The brain combines \nthe two images into a cohesive scene, and concurrently, \nperception is stable. However, when showing two very different \nimages (such as two different books) to each eye, the brain \nresolves the conflict by adopting a “diplomatic” strategy. Rather \nthan mixing the views of the two eyes into an insensible visual \npercept, observers perceive a dynamically changing series of \nperceptual snapshots, with one eye’s view dominating for a few \nseconds before being replaced by its rival from the other eye. \nWith prolonged viewing of a rivalrous stimulus, one inevitably \nexperiences a sequence of subjective perceptual reversals, separated \nby random time intervals, and this process continues for \nas long as the sensory conflict is present.