Colloquium Cognitive Systems

Perceiving a stationary world during head and eye movements

Prof. Paul MacNeilage (University of Nevada)

Abstract:
Head and eye movements lead to visual motion at the retina, but we seldom perceive the world as moving due to compensatory perceptual mechanisms. The importance of these mechanisms becomes apparent when compensation fails, leading to visual instability, dizziness and disorientation. This occurs for example during a variety of clinical conditions and in miscalibrated virtual and augmented reality systems. To investigate mechanisms of stationarity perception we have developed a psychophysical paradigm in virtual reality in which we manipulate the gain of visual scene motion and ask observers to report whether the gain was too fast or too slow. In a series of psychophysical experiments, we have varied properties of head, eye, and visual motion and observe how these influence stationarity perception. Results are interpreted in a signal detection framework and this allows inference about the sensory and motor signals involved. Open questions remain concerning the most appropriate framework to model these processes.
About:
 Dr. MacNeilage is Associate Professor and Director of the graduate program in Cognitive and Brain Sciences in the Department of Psychology at the University of Nevada Reno. He did his undergraduate degree at Harvard University and completed a PhD in Vision Science at the University of California, Berkeley.  He completed post-doctoral training in vestibular physiology and perception at Washington University School of Medicine and served as research group leader at the German Center for Vertigo and Balance Disorders at the Ludwig Maximillian University Hospital in Munich. His research is focused on psychophysical measurement and probabilistic modeling of human spatial orientation perception. This is supplemented by work characterizing the natural statistics of human head, eye, and visual motion to understand how these shape spatial orientation processes.