| Abstract: | Investigated differing predictions from the spatial mapping hypothesis of hippocampal function proposed by O'Keefe and Nadel (1978) and the working memory hypothesis proposed more recently by Olton and colleagues (Olton, Becker, & Handelmann, 1979). Each of 2 groups of rats was trained to use a different strategy to locate a submerged platform in opaque water. The MAP group used a spatial mapping strategy to reach a platform in a fixed location, whereas the CUE group used a guidance strategy, which involved following a cue that signaled the location of a randomly placed platform. Half of each group was given low-level unilateral electrical stimulation of the dentate gyrus and immediately tested on the water maze task. Results of Exp 1 show that both the MAP and CUE groups were impaired by stimulation. However, there was an inadvertent spatial element involved in the CUE task. When this element was eliminated in Exp 3, the same CUE Ss were unaffected by a 2nd series of stimulation trials, whereas the MAP Ss continued to show impairment. Results strongly support the cognitive mapping hypothesis and provide little support for the working memory hypothesis of hippocampal function. (PsycINFO Database Record (c) 2010 APA, all rights reserved) |
