Reconsolidation of fresh, remote, and extinguished fear memory in Medaka: old fears don't die.
Long-term fear memory in the medaka fish (Oryzias latipes) regains transient sensitivity to a consolidation blocker immediately after memory reactivation in retrieval ('reconsolidation'). Here we show that reconsolidation occurs in fresh long-term memories but not in remote memories, and that the apparent amnesia induced by blockade of reconsolidation can be reinstated by an unpaired reinforcer, a procedure that has no effect on amnesia induced by blockade of consolidation. Extinction memory also undergoes post-reactivation reconsolidation, the blockade of which exposes the previously acquired fear. Hence in medaka, the process manifested in reconsolidation seems itself to consolidate; moreover, even when the post-reactivation application of the consolidation blocker is still able to disrupt the memory, the conditioned fear does not seem to go away permanently.
Eisenberg
Mark
M
Department of Neurobiology, The Weizmann Institute of Science, Rehovot 76100, Israel.
Dudai
Yadin
Y
D062365:Aminobenzoates / Q000494:pharmacology; D000818:Animals; D003213:Conditioning, Psychological / Q000187:drug effects / Q000502:physiology; D004597:Electroshock / Q000379:methods; D005239:Fear / Q000187:drug effects / Q000502:physiology*; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D009990:Oryzias / Q000502:physiology*; D013995:Time
D062365:Aminobenzoates; C003636:tricaine