[Abstract Title]. - Society for Neuroscience

Poster
295. Memory Consolidation, Reconsolidation, Anatomy, and Mechanisms
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 295.5/SS55
Topic: F.02.h. Memory modulation, consolidation, and reconsolidation
Support: NIMH Grant R01 MH074736
NIMH Grant R01 MH65635
NARSAD Independent Investigator Award
Title: Memory reactivations strengthen memory retention and persistence
Authors: *J. S. RICEBERG, D. Y. CHEN, S. M. TAUBENFELD, C. M. ALBERINI;
Neurosci., Mount Sinai Sch. of Med., New York, NY
Abstract: Newly learned information is initially in a labile state and over time stabilizes into
long-term memory by a consolidation process requiring RNA and protein synthesis. Previously
established memories can also become transiently labile if reactivated, for example, by retrieval.
This post-reactivation phase again depends on new protein synthesis and is known as
reconsolidation. Why should a stabilized memory return to this vulnerable state? One hypothesis
proposes that the labile phase of reconsolidation mediates memory strengthening. Using a singletrial
inhibitory avoidance (IA) paradigm in rat, we tested whether reactivation exposures affect
memory strength. During IA, animals form an association between a CS (context) and a US
(foot-shock): reactivation of this memory typically consists of an exposure to the CS alone.
However, exposure to a non-reinforced CS can also elicit extinction learning, which results in a
decrease of the conditioned response. We used protocols that do not induce behavioral extinction
to test whether the strength and/or persistence of IA memory is affected by reactivation
exposures and whether these potential changes critically involve the labile phase of
reconsolidation. We found that the retention of IA memory is a graded function of the number of
reactivations. Results from experiments using both short (2-day) and long (7-day) interreactivation
intervals indicate that the incremental changes in memory retention contribute to
both strengthening and preventing the decay of memory. These findings support the hypothesis
that single-trial fear memories are strengthened and maintained through reactivation/s of the
original experience.
Disclosures: J.S. Riceberg , None; D.Y. Chen, None; S.M. Taubenfeld, None; C.M. Alberini,
None.