|The search for an endogenous function for the process of reconsolidation remains a fundamental issue. As noted by Dudai (2007), reconsolidation might not serve any function, particularly given the remote chance of encountering in everyday life the forms of agents used experimentally to induce amnesia. Nevertheless, interference is a potent cause of amnesia in reconsolidation studies (e.g., Walker et al., 2003; Hupbach et al., 2007) and stress can also be detrimental to reactivated memories (Maroun & Akirav, 2008; Wang et al., 2008), thereby suggesting that retrieval-induced plasticity places a memory trace at risk of disruption. As such, reconsolidation has been conceptualized as a fundamental process in the ongoing modification and storage of memories.
Indeed, it has often been suggested that reconsolidation might enable memories to be
modified or updated (e.g., Tronson & Taylor, 2007; Dudai & Eisenberg, 2004; Sara, 2000).
Generally, memories are retrieved in circumstances wherein additional complementary
information is presented. As such, the capacity for plastic alterations in memory strength or
content following memory retrieval would appear adaptive in terms of maintaining a
memory’s relevance with respect to guiding future behaviour (Lee, 2009). Indeed, in terms of
human episodic memories, interference congruent with retrieval of a prior memory results in
an incorrectly updated memory for a list of items (Hupbach et al., 2007), thereby suggesting
a role of reconsolidation in updating memories. However, Tronel and colleagues (2005), in a
study adopting inhibitory avoidance learning in rats, did not find evidence that [reconsolidation is functionally involved in linking new information to a reactivated memory.]
While much has been learned regarding the mechanisms of reconsolidation, the search for an endogenous function of the process remains a fundamental issue. As noted by Dudai , reconsolidation might not serve any function, especially given the remote chance of encountering in real life the kinds of agents used experimentally to induce amnesia. Nevertheless, interference is a potent cause of amnesia in reconsolidation studies [12-14], and stress can also be detrimental to reactivated memories [15, 16], suggesting that retrieval-induced plasticity does place a memory genuinely at risk of disruption.
It has often been suggested that reconsolidation may enable memories to be modified or
updated [5, 8, 9, 13, 17, 18]. Memories are retrieved often in situations presenting additional
complementary information. Thus the capacity for plastic changes in memory strength or
content following memory retrieval seems potentially adaptive in terms of maintaining a
memory’s relevance in guiding future behaviour. [Three studies are of direct relevance to the
hypothesis that reconsolidation mediates memory updating (see Box 1 for brief experimental
details of the following tasks).] Firstly, in human episodic memories, interference congruent
with retrieval of a prior memory results in an incorrectly updated memory for a list of items
. This finding is consistent with, though not directly demonstrative of, a role of
reconsolidation in updating memories. Moreover, a prior study of inhibitory avoidance
learning in rats did not provide evidence that reconsolidation is functionally involved in
linking new information to a reactivated memory .
Thus reconsolidation may be viewed as a
fundamental process in the ongoing modification and storage of memories.
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