2011-05-20 at 14:00
UMR 7102 - Neurobiology of Adaptive Processes, University Pierre and Marie Curie, Paris 6, Building B, 5th floor, Room 501 (How to come)
The Geometry(ies) of Spatial Knowledge for Navigation
It is often assumed that “cognitive maps in rats and men” (Tolman,1948) have a Euclidean geometric structure. Such spatial knowledge might be built up from path integration by vector subtraction (Gallistel, 1990), and would support accurate shortcuts and detours. However, apparently Euclidean behavior may also result from weaker knowledge together with some adaptive navigation strategies. We use an ambulatory virtual environment to investigate active navigation in walking humans. Results indicate that humans have poor path integration that serves as a back-up system, rely heavily on visual landmarks and topological structure, and tolerate radical violations of Euclidean structure, but can fall back on coarse metric information when necessary. Spatial knowledge is thus not integrated into a globally consistent cognitive map, but might be characterized as a weighted oriented graph that is primarily topological, but can be used to generate rough metric paths on the fly.
William Warren is Chancellor’s Professor of Cognitive, Linguistic, and Psychological Sciences at Brown University. He earned an undergraduate degree at Hampshire College (1976) and a Ph.D. in Experimental Psychology from the University of Connecticut (1982). He uses virtual reality techniques to study the visual control of human locomotion and navigation, with funding from NIH and NSF. Warren is author of over 85 research articles and chapters, the editor of two volumes, and the recipient of a Fulbright Research Fellowship, an NIH Research Career Development Award, and Brown's Elizabeth Leduc Teaching Award for Excellence in the Life Sciences.