Edgar Pierce Professor of Psychology
Vision Sciences Laboratory
I received a B.A. from Haverford College and a Ph.D. from UCLA. From 1971 to 1990 I was at the Smith Kettlewell Eye Research Institute in San Francisco. Since 1990 I have been in the Department of Psychology at Harvard University.
Research Questions and Interests
How do we see? What is it about the ever changing structure of light impinging on our mobile eyes that enables us to pick up information about the environment around us? What is it about our brain and its neural activity allows us to see so much and so effortlessly? How is it that we can control our eyes and bodies to seek out information and to act in the physical world? These are just some of the large questions that drive researchers, including myself, to study vision. We find it a fascinating topic because it seems both so accessible and yet so elusive. Vision is immediate and obvious, so much so that it seems not to require any explanation. Yet, if we think of how an imaginary robot might simulate a human or how neural circuits might mediate conscious visual perception, we come to realize how deep the gulf is between what we know about the brain and the everyday facts about visual perception.
Scientists find it difficult to tackle such large questions directly and few have done so successfully. Most of us find it more fruitful to study particular areas in the hope that we may better glimpse partial answers to such large questions. We learn from neuroanatomy that the territory of the brain devoted to vision is huge, approximately 50% in non-human primates and almost as large in humans. This suggests an enormity to vision that is still to be fully acknowledged. In terms of sheer brain power, vision is comparable to the whole rest of the brain put together. As such, we need to realize that vision isn't simply one thing, that there are likely to be many visual functions. We are just beginning to appreciate that seeing and getting around in the world requires many unknown processes that we have yet to discern. Some of these functions become evident with brain damage, for example, when an individual cannot see motion or cannot recognize faces.
My own research strategy has been to isolate a variety of visual functions and to study them in detail. To do this, I have relied heavily on the discipline of visual psychophysics which constitutes a surprisingly powerful set of concepts and procedures. Over the years I've been privileged to have worked with outstanding colleagues and students. Occasionally, we were lucky enough to make a genuine new discovery or to gain greater insight into how pieces of the visual puzzle fit together. Recently, I have worked on the representation of visual surfaces, the deployment of visual attention, and the role of attention in initiating eye movements. Most recently, I have become interested in the perception and recognition of faces. I am also interested in using visual psychophysical tests to assess neurological and psychiatric disorders. In the future, I hope that the study of faces will help us understand social perception and cognition, illuminating how we represent other humans at a non-verbal level.
Prosopagnosia Research Center