Jeremey M. Wolfe, PhD
Professor of Ophthalmology and Radiology, Harvard Medical School
Talk Title: If I can see so much, why do I miss so much?
Abstract: When you open your eyes on a new scene, you immediately see something. You can understand the basic ‘gist’ of that scene within a fraction of a second. You can remember that scene for days after only a few seconds exposure. Nevertheless, we can easily show that you are ‘blind’ or at least remarkably amnesic about very basic aspects of what you have just seen.
These various forms of“blindness” arise from the capacity limits of the nervous system. Your ability to process the visual stimuli that land on your retina is severely restricted. Visual search tasks make this point very clearly. Think about a Where’s Waldo task. Waldo is right there, in front of your eyes. Yet, you need to search for him. Fortunately, you don’t search at random. There is a limited set of basic features (e.g. those red stripes) that can guide your attention, but until you direct attention to the object that happens to be Waldo, you simply do not know if he is present or not. The same principle holds even if the stimuli are much less crowded and less deliberately difficult. Indeed, in the real world, the processes of guidance are so effective that you often do not notice the searches of everyday life. So your hand finds the coffee mug or the fork without apparent effort, even though the search is similar in kind to your search for Waldo.
In our modern civilization, we have created socially important tasks like airport security and cancer screening that have very substantial visual search components. We want experts to do these tasks perfectly, but they are doing them with a human visual search apparatus that makes perfection unlikely, at best. Worse, these tasks often have properties (e.g. very rare targets) that make the tasks more difficult for humans. This talk will illustrate the problems and discuss possible solutions.
About: Jeremy Wolfe is Professor of Ophthalmology and Professor of Radiology at Harvard Medical School. He is Director of the Visual Attention Lab and the Center for Advanced Medical Imaging at Brigham and Women's Hospital. Wolfe received an AB in Psychology in 1977 from Princeton and his PhD in Psychology in 1981 from MIT under the supervision of Richard Held. His research focuses on visual search and visual attention with a particular interest in socially important search tasks in areas such as medical image perception (e.g. cancer screening), security (e.g. baggage screening), and intelligence. He is Immediate Past-Chair of the Psychonomic Society and just ended his term as Editor of Attention, Perception, and Psychophysics.