Part of Advances in Neural Information Processing Systems 8 (NIPS 1995)
A. Redish, David Touretzky
We have developed a computational theory of rodent navigation that includes analogs of the place cell system, the head direction system, and path integration. In this paper we present simulation results showing how interactions between the place and head direction systems can account for recent observations about hippocampal place cell responses to doubling and/or rotation of cue cards in a cylindrical arena (Sharp et at., 1990).
Rodents have multiple internal representations of their relationship to their environment. They have, for example, a representation of their location (place cells in the hippocampal formation, see Muller et at., 1991), and a location-independent representation of their heading (head direction cells in the postsubiculum and the anterior thalamic nuclei, see Taube et at., 1990; Taube, 1995). If these representations are to be used for navigation, they must be aligned consistently whenever the animal reenters a familiar environment. This process was examined in a set of experiments by Sharp et at. (1990).
1 The Sharp et al., 1990 experiment
Rats spent multiple sessions finding food scattered randomly on the floor of a black cylin(cid:173) drical arena with a white cue card along the wall subtending 90° of arc. The animals were not disoriented before entering the arena, and they always entered at the same location: the northwest corner. See Figure 3a. Hippocampal place fields were mapped by single-cell recording. A variety of probe trials were then introduced. When an identical second cue
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A. D. REDISH, D. S. TOURETZKY