Linking new information to a reactivated memory requires consolidation and not reconsolidation mechanisms

PLoS Biol. 2005 Sep;3(9):e293. doi: 10.1371/journal.pbio.0030293. Epub 2005 Aug 23.

Abstract

A new memory is initially labile and becomes stabilized through a process of consolidation, which depends on gene expression. Stable memories, however, can again become labile if reactivated by recall and require another phase of protein synthesis in order to be maintained. This process is known as reconsolidation. The functional significance of the labile phase of reconsolidation is unknown; one hypothesis proposes that it is required to link new information with reactivated memories. Reconsolidation is distinct from the initial consolidation, and one distinction is that the requirement for specific proteins or general protein synthesis during the two processes occurs in different brain areas. Here, we identified an anatomically distinctive molecular requirement that doubly dissociates consolidation from reconsolidation of an inhibitory avoidance memory. We then used this requirement to investigate whether reconsolidation and consolidation are involved in linking new information with reactivated memories. In contrast to what the hypothesis predicted, we found that reconsolidation does not contribute to the formation of an association between new and reactivated information. Instead, it recruits mechanisms similar to those underlying consolidation of a new memory. Thus, linking new information to a reactivated memory is mediated by consolidation and not reconsolidation mechanisms.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amygdala / drug effects
  • Amygdala / physiology
  • Animals
  • Anisomycin / pharmacology
  • Avoidance Learning / drug effects*
  • Avoidance Learning / physiology
  • Conditioning, Classical / drug effects*
  • Conditioning, Classical / physiology
  • Hippocampus / drug effects
  • Hippocampus / metabolism
  • Memory / drug effects
  • Memory / physiology*
  • Mental Recall / drug effects
  • Mental Recall / physiology*
  • Models, Neurological
  • Protein Synthesis Inhibitors / pharmacology
  • Rats
  • Rats, Long-Evans

Substances

  • Protein Synthesis Inhibitors
  • Anisomycin