What does the hippocampus really do?

doi:10.1016/0166-4328(95)00034-8

Behavioural Brain Research

Volume 71, Issues 1–2, November 1995, Pages 1-10

https://doi.org/10.1016/0166-4328(95)00034-8 Get rights and content

Abstract

Much of the evidence used to implicate the hippocampus in learning and memory has been obtained from clinical cases and/or experimental studies with animals where the damage is extensive and includes more than just the hippocampus. When the damage is limited to the cells that comprise the hippocampus (CA1–CA3 pyramidal cells, hilar and granule cells in the dentate gyrus) the effect on behavior in the rat is more limited than what is usually reported. Selective, axon-sparing ibotenic acid lesions of the hippocampus were used in the experiments that are reviewed to study the effects of removing the hippocampus on: (1) the acquisition of spatial and non-spatial information; (2) complex, non-spatial representational learning; and (3) acquisition and utilization of contextual information. The results indicated that rats with the hippocampus removed were impaired on those tasks that require the utilization of spatial and contextual information but performed like controls in learning about and handling (even complex) non-spatial information. Future research utilizing selective lesions of the hippocampus and sensitive behavioral testing techniques should help clarify the extent to which the impairments in the acquisition of spatial information and the ability to utilize contextual, background cues can be reduced to a single, underlying learning process.

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Citation Excerpt :
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Research reportWhat does the hippocampus really do?

Abstract

Neuroscience

Behav. Neur. Biol.

Behav. Biol.

J. Neurosci. Methods

Behav. Neural Biol.

Trends Neurosci.

Behav. Brain. Res.

Neuroscience

Acquisition of a complex place task in rats with selective ibotenate lesions of hippocampal formation: combined lesions of subiculum and entorhinal cortex vs. hippocampus

Behav. Neurosci.

Context and retrieval in extinction and in other examples of interference in simple associative learning

Context, ambiguity and classical conditioning

Curr. Direct. Psychol. Sci.

H.M.'s MRI scan shows sparing of the posterior half of the hippocampus and parahippocampal gyrus

Soc. Neurosci. Abstr.

Retention of concurrent conditional discriminations in rats with ibotenate lesions of hippocampus

Psychobiology

Hippocampal leisons do not impair negative patterning: a challenge to configural association theory

Behav. Neurosci.

Two functional components of the hippocampal memory system

Behav. Brain Sci.

Amnesia for complex naturalistic scenes and for objects following fornix transection in the Rhesus monkey

Eur. J. Neurosci.

Preserved configural learning and spatial learning impairment in rats with hippocampal damage

Hippocampus

Autoradiographic studies of the commissural and ipsilateral association connection of the hippocampus and dentate gyrus of the rat. I. The commissural connections

J. Comp. Neurol.

The hippocampus

Research report
What does the hippocampus really do?