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. 1994 Dec 20;91(26):12673–12675. doi: 10.1073/pnas.91.26.12673

An increase in dendritic spine density on hippocampal CA1 pyramidal cells following spatial learning in adult rats suggests the formation of new synapses.

M B Moser 1, M Trommald 1, P Andersen 1
PMCID: PMC45501  PMID: 7809099

Abstract

The search for cellular correlates of learning is a major challenge in neurobiology. The hippocampal formation is important for learning spatial relations. A possible long-lasting consequence of such spatial learning is alteration of the size, shape, or number of excitatory synapses. The dendritic spine density is a good index for the number of hippocampal excitatory synapses. By using laser-scanning confocal microscopy, we observed a significantly increased spine density in CA1 basal dendrites of spatially trained rats when compared to nontrained controls. With unchanged dendritic length, the higher spine density reflects an increased number of excitatory synapses per neuron associated with spatial learning.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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