Hippocampectomized rats can use a constellation of landmarks to recognize a place

The hippocampus, one of the most studied regions of the mammalian forebrain , plays some well-established roles in topographic navigation. For two deca des, one widely accepted explanation for the observed impairment of hippoca mpectomized rats in spatial navigation has been an inability to form place representations. In this report, we present a direct experimental evidence that animals with hippocampal lesions can learn to recognize places using t he constellation of distinct landmarks. The extrahippocampal implementation of all three basic constituents of topographic orientation - guidance, vec tor navigation, and place recognition - shows that the hippocampus, and its place cells, serve a much more specialized cognitive function than previou sly thought. We propose that this function includes multi-place and multi-v ector topographic integration. (C) 2000 Elsevier Science B.V. AU rights res erved.