Neural Correlates of Binocular Rivalry

Princeton University, Princeton NJ

Investigators

Abstract

The typical visual scenes that we view in everyday life are cluttered and contain numerous items that cannot all be processed at the same time. Only few visual objects are selected for further processing and reach the level of awareness. But what is the relationship between awareness and neural activity in the brain? The subjective nature of conscious perception has posed a serious problem to neuroscientists in approaching the study of the neural correlates of consciousness. However, in recent years, a few paradigms have been developed that promise to overcome some of these issues. With support of the National Science Foundation, Dr. Sabine Kastner and colleagues at Princeton University will study neural correlates of conscious perception using a binocular rivalry paradigm. In binocular rivalry, two incompatible stimuli (e.g. a face and a house) are presented to the two eyes, which leads to a competition for conscious perception such that only one image is visible at a time while the other one is suppressed from awareness. As a result, viewers perceive either the face or the house, but not both. Because the viewers' perceptual experiences change over time while the physical stimulus on the retina remains constant, binocular rivalry provides an intriguing paradigm to study the neural basis of visual awareness. Dr. Kastner will perform non-invasive functional brain imaging studies in humans and monkeys using a variety of rivalrous stimuli. These studies will identify the brain networks that are engaged during the conscious perception of visual information. The comparison of brain activations in humans and monkeys will provide important insights regarding conscious perception. This work will result in a better understanding of one of the most fundamental issues in cognitive neuroscience, the neural substrates underlying conscious perception. The results of these studies may also be of interest to other fields outside neuroscience such as philosophy. The combination of neuroimaging in humans and monkeys is performed only in few laboratories in the world and offers a unique training opportunity for trainees at all levels of education, including undergraduate and graduate students. Results will be broadly disseminated through publications, public lectures and public databases to scientific as well as general public audiences.