[Abstract Title]. - Society for Neuroscience

Topic: F.02.h. Memory modulation, consolidation, and reconsolidation
Support: NSERC
CIHR
Title: The relationship between auditory and contextual memory in Pavlovian fear conditioning
Authors: *M. J. HONSBERGER, K. NADER;
Psychology, McGill Univ., Montreal, QC, Canada
Abstract: In Pavlovian auditory fear conditioning shock paired with a tone can lead to
conditioned responses, such as freezing, being elicited by both the training context and tone.
Conditioned responses elicited by the tone are often assessed by presenting the conditioned tone
in a novel context in order to minimize confounds due to contextual freezing induced by the
training context. Therefore, the training of auditory fear conditioning results in two fear
memories, auditory and contextual. It remains unclear whether the context and the tone are part
of the same fear memory or have their own fear representation. We have begun to address this by
exploiting the fact that fear memories have been shown to undergo reconsolidation in the
basolateral amygdala (BLA) following reactivation. Previously we showed that blocking
reconsolidation of contextual fear conditioning led to an impairment in freezing to the tone, even
though the tone was not reactivated. Conversely, blocking reconsolidation of auditory fear
conditioning had no effect on freezing induced by the context. We reasoned that one possible
explanation of these results is that in order for the tone to normally express freezing, it requires
an intact context-shock association. For example, perhaps the single pairing protocol used led to
a serial tone-context-shock association. In the present experiment, we tested this hypothesis by
extinguishing either the auditory or contextual fear memories. If these two memories are serially
associated then only the extinction of the CS directly associated with the shock should result in
both memories showing reduced freezing. Preliminary results suggest that similar to our previous
experiment, extinction of the tone only effects the auditory fear memory. However, preliminary
results indicate that extinction of the context results in reduced freezing to both the context and
tone. This suggests that the auditory fear memories acquired during Pavlovian fear conditioning
are not independently acquired.
Disclosures: M.J. Honsberger , None; K. Nader, None.
Poster
295. Memory Consolidation, Reconsolidation, Anatomy, and Mechanisms
Time: Sunday, November 16, 2008, 1:00 pm - 5:00 pm
Program#/Poster#: 295.19/SS69