Hippocampal long-term depression: master or minion in declarative memory processes?

Trends Neurosci. 2007 Mar;30(3):111-8. doi: 10.1016/j.tins.2007.01.002. Epub 2007 Jan 17.


The neural mechanisms for the formation of declarative memory (memory for facts and events) are believed to be integrated from processes mediated by hippocampal long-term potentiation (LTP) and long-term depression (LTD). Traditionally, LTP has been designated as the main mediator of spatial memory storage in the hippocampus, whereas LTD has been assigned an auxiliary role in signal-to-noise regulation or in forgetting. It has recently become apparent, however, that LTD contributes directly to hippocampal information storage. In fact, LTD could dominate in the processing of precise spatial characteristics. Accumulating evidence supports the idea that LTP and LTD enable distinct and separate forms of information storage, which together facilitate the generation of a spatial cognitive map.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Hippocampus / physiology*
  • Humans
  • Learning / physiology*
  • Long-Term Potentiation / physiology
  • Long-Term Synaptic Depression / physiology*
  • Memory / physiology*
  • Space Perception / physiology*