LeDoux Lab 2009 SfN Abstracts
 
Program#/Poster#: 479.20/FF121
Title: Reconsolidation of implicitly reactivated fear memories in the rat amygdala
Location: South Hall A
Presentation Time: Monday, Oct 19, 2009, 4:00 PM - 5:00 PM
Authors: *J. DEBIEC1,2, V. DOYERE1,3, L. DIAZ-MATAIX1, D. E. A. BUSH1, J. E. LEDOUX1,4;
1Ctr. for Neural Sci., 2Dept. of Psychiatry, New York Univ., New York, NY; 3N.a.m.c, c.n.r.s.-u.m.r8620, Univ. Paris-Sud, Orsay, France; 4Emotional Brain Inst., Nathan S. Kline Inst. for Psychiatric Res., Orangeburg, NY
Abstract: Existing data demonstrate a key role of the amygdala in acquisition, consolidation and maintenance of fear learning. Reactivation of fear memories by presenting a learning cue (conditioned stimulus, CS) renders them labile and initiates protein synthesis dependent reconsolidation processes in the lateral nucleus of the amygdala (LA). Using a second-order fear conditioning task, we have recently demonstrated that reactivation of a single memory does not render associated memories labile (Debiec et al, 2006). However, associations between stimuli may have a different status when they are bound through within compound associations. Here we use a compound fear conditioning protocol with a compound tone-light CS (L+T Comp) and a footshock US in order to ask whether presenting a part of the compound CS would render the other part of the L+T Comp labile. We first show that exposure to the light 24 hours after conditioning, followed by intra-LA infusions of protein synthesis inhibitor anisomycin (with artificial cerebro-spinal fluid, ACSF used as a vehicle control) impairs fear responding (freezing) to the L+T Comp on the following day. In another group of rats, we show that after reactivation of the memory by presenting the light, intra-LA infusion of anisomycin produces deficits in freezing responding to the tone, the other part of the compound CS. This pattern of findings suggests that an exposure to the part of the compound renders the other part of the compound labile and protein synthesis dependent. Thus, concurrent presentation of distinct stimuli during a compound fear conditioning procedure leads to a formation of associations such that a reactivation of one stimulus initiates reconsolidation of another part of the compound. Therefore, within compound associations may provide each element different status with regard to its reconsolidation capability.
Support: R37 MH038774 to J.E.L.
P50 MH058911 to J.E.L.
R01 MH046516 to J.E.L.
CNRS-PICS to V.D. & J.E.L.
CNRS-UPS-NYU EmoTime to V.D. & J.E.L.