The Role of Reconsolidation and the Dynamic Process of Long-Term Memory Formation and Storage

Abstract

It is becoming increasingly clear that the processes of memory formation and storage are exquisitely dynamic. Elucidating the nature and temporal evolution of the biological changes that accompany encoding, storage, and retrieval is key to understand memory formation. For explicit or medial temporal lobe-dependent memories that form after a discrete event and are stored for a long time, the physical changes underlying the encoding and processing of the information (memory trace or engram) remain in a fragile state for some time. However, over time, the new memory becomes increasingly resistant to disruption until it is consolidated. Retrieval or reactivation of an apparently consolidated memory can render the memory labile again, and reconsolidation is the process that occurs to mediate its restabilization. Reconsolidation also evolves with the age of the memory: Young memories are sensitive to post-reactivation disruption, but older memories are more resistant. Why does a memory become labile again if it is retrieved or reactivated? Here I suggest that the main function of reconsolidation is to contribute to the lingering consolidation process and mediate memory strengthening. I also discuss the literature and results regarding the influence of the passage of time on the reconsolidation of memory. These points have important implications for the use of reconsolidation in therapeutic settings.

Choline reverses scopolamine-induced memory impairment by improving memory reconsolidation

“…Since the reminder that induce reconsolidation is also a part of the cues presented during training, but the unconditioned stimulus (US) is not presented after the conditioned stimulus (CS), new information is available for being learned and other processes emerge as candidates for explaining any post-retrieval effect, like extinction (Myers and Davis, 2002). Standard controls determine that retention performance should not be affected if the treatment is administered in absence of memory reactivation or showing that the post-retrieval treatment needs to be given before the end of a temporal window to be effective (Alberini, 2011;Alberini, Milekic, & Tronel, 2006;Dudai, 2006;Misanin, Miller, & Lewis, 1968;Przybyslawski & Sara, 1997;Tronson & Taylor, 2007). However, none of these controls can completely discard that a new learning process is occurring, and that it is the actual responsible for performance in subsequent tests.…”

Influence of reward motivation on human declarative memory

“…Recent theories on reconsolidation propose that long-term memory formation implicates memory recollection, because the hippocampus links encoded information to reactivated memories in a continuous cycle of retrieval and learning (Alberini, 2011;Forcato et al, 2007;McKenzie and Eichenbaum, 2011;Stickgold and Walker, 2013). In this context, the circuits modulated by new learning are the ones that are activated by the reminder of a remembered (e.g.…”

On the Dynamic Nature of the Engram: Evidence for Circuit-Level Reorganization of Object Memory Traces following Reactivation

“…To persist, this labile memory must be reconsolidated. The process of postreactivation memory destabilization and reconsolidation has been demonstrated in numerous species and for myriad memory types (Misanin et al, 1968;Sara, 2000;Nader, 2003;Hardt et al, 2010;Alberini, 2011), including object recognition memory (Bozon et al, 2003;Kelly et al, 2003;Akirav and Maroun, 2006;Rossato et al, 2007;Maroun and Akirav, 2008;Lima et al, 2009;Winters et al, 2009;Davis et al, 2010;Romero-Granados et al, 2010).…”