Hippocampal synaptic enhancement and spatial learning in the Morris swim task

Donna L Korol, T. W. Abel, L. T. Church, C. A. Barnes, B. L. McNaughton

Research output: Contribution to journalArticle

50 Scopus citations


The authors attempted to replicate the study of Castro, Silbert, McNaughton, and Barnes (1989) in which it was concluded that bilateral saturation of hippocampal synaptic enhancement produced a deficit in acquisition of a spatial navigation problem in the Morris swim task. The original protocol was followed as closely as possible, but no effect of long-term enhancement (LTE) saturation on spatial performance in this task was found. This negative result suggests either that the previous finding using the swim task reflected statistical error or that some as yet undetermined variable is of critical importance in this phenomenon. The present negative finding also raises a question concerning the reproducibility of the earlier results, in which LTE saturation apparently led to a prolonged deficit on a different spatial task. Although negative results in such experiments do not constitute grounds for rejecting the underlying hypothesis, the present lack of a positive effect renders uncertain, for the time being, one of the lines of experimental support for the theory that LTE at hippocampal synapses reflects a mechanism for the associative, distributed storage of new spatial information.

Original languageEnglish (US)
Pages (from-to)127-132
Number of pages6
Issue number2
StatePublished - 1993
Externally publishedYes



  • Long-term enhancement
  • LTP saturation
  • Spatial information storage
  • Synapse

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this

Korol, D. L., Abel, T. W., Church, L. T., Barnes, C. A., & McNaughton, B. L. (1993). Hippocampal synaptic enhancement and spatial learning in the Morris swim task. Hippocampus, 3(2), 127-132.