Dichotomies of the Visual Brain
Paper by Dr Steven Miller
"The changing face of perceptual rivalry."
Abstract:
For several hundred years, and probably much longer, it has been known that the brain has a unique way of dealing with visual conflict. Present two different images simultaneously, one to each eye, and rather than superimpose the two images, the brain perceives each in alternation, every few seconds. This phenomenon of binocular rivalry, which requires mirrors or goggles to induce, has a counterpart in normal viewing of 2-D reversible figures such as the Necker cube and Rubin’s vase-faces illusion. Because all these phenomena involve distinct perceptual flips every few seconds, despite the unchanging visual input, it is hardly surprising that several investigators have proposed that they share a common neural mechanism. What is surprising, however, is that a common mechanism, if indeed there is one, has remained elusive despite intense neuroscientific research over the last 20 years and psychophysical research over the last 100 years.
In this talk, I survey the landscape of perceptual rivalry research and present the rationale and evidence for a novel explanatory model – the interhemispheric switch hypothesis. I present a series of brain stimulation studies in support of this model that I have conducted over the last 10 years with colleagues, Jack Pettigrew and Trung Ngo. This model proposes that the substantial high-level attentional resources of each cerebral hemisphere are employed independently and in alternation, to achieve the perceptual alternations of binocular rivalry and reversible figures. I conclude with some brief remarks on the scientific study of consciousness, as well as brain stimulation approaches to experimental neurophilosophy.
Dr Miller will present this paper at 3.15 pm on Tuesday, June 17th, 2008.
With any queries, please contact Dr Jakob Hohwy, Ph: (03) 9905 3208; Email: jakob.hohwy@arts.monash.edu.au.
Back to details on "Dichotomies of the visual brain".