An attractor model for hippocampal place cell hysteresis

It is well-known that identical sensory input under different perceptual, b ehavioral or contextual conditions can produce distinct patterns of activit y in the place cells of the rodent hippocampus. However, the mechanisms und erlying this have not been completely clarified. A recent experiment has sh own that place cell activity on a 3-arm maze exhibits hysteresis as the maz e is rotated with respect to distal cues. The apparent angular extent of a place field is greater when a maze arm rotates out of it than when it rotat es back into the held. In this report, we present a simple attractor-based model of the hippocampus that reproduces this hysteresis phenomenon. The mo del allows us to make predictions about changes in the hysteresis effect as the animal becomes more familiar with the maze in several orientations. It also has implications for the place field remapping phenomenon seen in man y hippocampal experiments. (C) 2001 Elsevier Science B.V. All rights reserv ed.