Orientation specificity in representations of place.

How organisms code information that allows them to recognize one place in space as distinct from another has been studied neuroanatomically, neurophysiolo gically, and behaviorally in animals. Neurophysiological studies with rats show that cells in CA1 and CA3 regions of the hippocampus respond selectively to the place occupied by a rat, with one place being discriminable from another by its unique configuration of surrounding, local cues (e.g., Muller, Kubie, Bostock, Taube, & Quirk, 1991; O'Keefe, 1979; O'Keefe & Speakman, 1987). A place cells' sensitivity to cue configurations is indicated by its diminished response following a change in the relative location of the cues but by little change in its response rate if one cue is removed from the configuration, as long as the spatial relations among the remaining cues are preserved (O'Keefe, 1979; O'Keefe & Conway, 1978). Findings showing that hippocampal lesions severely disrupt a rat's ability to learn the place occupied by the goal but leave intact its ability to learn an egocentrically defined route to the goal provide behavioral evidence for the role of the hippocampus in cognitive mapping (e.g., O'Keefe &Nadel, 1978). Place learning has been studied behaviorally in human adults on a more limited scale than it has in animals, in part, because it is difficult to control and manipulate large-scale visual environments. Studies that focus on how people cognitively represent configurations of visual cues that can