Place units in the hippocampus of the freely moving rat

doi:10.1016/0014-4886(76)90055-8

Experimental Neurology

Volume 51, Issue 1, 1976, Pages 78-109

https://doi.org/10.1016/0014-4886(76)90055-8 Get rights and content

Abstract

Single units were recorded from the CA1 field of the hippocampus in the freely-moving rat. They were classified as place units, displace units or others. Place units were defined as those for which the rat's position on the maze was a necessary condition for maximal unit firing. Some of these place units (misplace units) fired maximally when the animal sniffed in a place, either because it found something new there or failed to find something which was usually there. Displace units increased their rates during behaviors associated with theta activity in the hippocampal slow waves. In general these were behaviors which changed the rat's position relative to the environment. The influence of various environmental manipulations (e.g., turning off the room lights) on the firing pattern of the place units was tested and the results suggest that they were not responding to a simple sensory stimulus nor to a specific motor behavior. Nor could the unit firing be due purely to motivational or incentive factors. The results are interpreted as strong support for the cognitive map theory of hippocampal function.

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¹: This work was supported by the Science Research Council and the Wellcome Trust. I would like to thank L. Nadel, A. H. Black, J. Ranck and P. D. Wall for encouragement, advice, criticism and consolation. E. G. Merrill, A. Ainsworth and S. Lazareno helped on the technical side.

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Place units in the hippocampus of the freely moving rat

Abstract

A technique for recording units in the medulla of awake, freely moving rats

J. Physiol. (London)

Studies on single neurones in dorsal hippocampal formation and septum in unrestrained rats. II. Hippocampal slow waves and theta cell firing during bar pressing and other behaviours

Exp. Neurol.

A versatile high impedance low-noise headstage

J. Physiol. (London)

Glass-coated platinum-plated tungsten microelectrodes

Med. Biol. Eng.

The hippocampus in pieces and patches: an essay on modes of explanation in physiological psychology

The hippocampus as a spatial map. Preliminary evidence from unit activity in the freely moving rat

Brain Research

Fornix lesions selectively abolish place learning in the rat

Exp. Neurol.