Reconsolidation: maintaining memory relevance

Abstract

The retrieval of a memory places it into a plastic state, as a result of which the memory can be disrupted or even enhanced by experimental treatment. This phenomenon has been conceptualised within a framework of memories being reactivated and then reconsolidated in repeated rounds of cellular processing. The reconsolidation phase has been seized upon as critical for the understanding of memory stability, and more recently as a potential therapeutic target in the treatment of disorders such as post-traumatic stress and drug addiction. However, little is known about the reactivation process, nor what might be the adaptive function of retrieval-induced plasticity. Reconsolidation has long been proposed to mediate memory updating, but only recently has this hypothesis been supported experimentally. Here, the adaptive function of memory reconsolidation is explored in more detail, with a strong emphasis on its role in updating memories to maintain their relevance.

Cholinergic manipulations bidirectionally regulate object memory destabilization

“…Reactivation or recall can render previously consolidated memories labile and sensitive to modification; this necessitates a timedependent process, referred to as reconsolidation, to restabilize the memory (Lewis 1979;Nader et al 2000;Sara 2000;Lee 2009;Nader and Hardt 2009). Whereas much research has elucidated the neural mechanisms subserving post-retrieval reconsolidation (Alberini 2005;Tronson and Taylor 2007;Nader and Hardt 2009), the neural bases of reactivation-induced memory destabilization have only recently received the same kind of attention (Lee 2009;Kaang and Choi 2011).…”

“…Whereas much research has elucidated the neural mechanisms subserving post-retrieval reconsolidation (Alberini 2005;Tronson and Taylor 2007;Nader and Hardt 2009), the neural bases of reactivation-induced memory destabilization have only recently received the same kind of attention (Lee 2009;Kaang and Choi 2011). A better understanding of the behavioral and neural factors contributing to memory destabilization is crucial given its permissive role in the reconsolidation process.…”

“…Indeed, not all memories become labile when reactivated; boundary conditions, including the strength of initial memory encoding and the age of the memory at the time of retrieval, determine the likelihood of destabilization upon reactivation (Milekic and Alberini 2002;Eisenberg and Dudai 2004;Suzuki et al 2004;Winters et al 2009). These boundary conditions may be related to the putative role of reconsolidation in memory updating (Sara 2000;Rodriguez-Ortiz et al 2005;Morris et al 2006;Hupbach et al 2007;Rossato et al 2007;Lee 2009;Forcato et al 2010;Sevenster et al 2013). Accordingly, stronger or more remote memories may be less likely to be altered in the absence of salient novel information (Lee 2009;Winters et al 2009).…”

Neutral mood induction during reconsolidation reduces accuracy, but not vividness and anxiety of emotional episodic memories

“…The purpose was to create a mismatch between what was expected and what was actually seen. This reminder structure has been effective in triggering reconsolidation because it disrupts expectation (i.e., a mismatch; Lee, 2009, Coccoz, Maldonado, & Delorenzi, 2011. Furthermore, for the two reactivation groups, after the reminder, a new movie (either neutral or positive) was presented after a 3-minute interval.…”

Effects of psychosocial stress on episodic memory updating

“…In contrast, reactivation accompanied by increased attention or arousal (Sara, 2000a, b) or additional exposure to the same materials (Lee, 2008) may strengthen a memory trace. Finally, new information may be incorporated into the reactivated memory trace, yielding updating rather than interference (Hupbach et al, 2008;Lee, 2009Lee, , 2010. Following reactivation, the memory trace undergoes re-consolidation to stabilize the memory representation again.…”