Seite: 44, Zeilen: 6-24
|Quelle: Lee 2009|
Seite(n): 2, 6, Zeilen: 2: 12-24, 26-31; 6: last lines
|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.
5. Tronson NC, Taylor JR. Molecular mechanisms of memory reconsolidation. Nat Rev Neurosci. 2007; 8:262–275. [PubMed: 17342174]
8. Dudai Y, Eisenberg M. Rites of passage of the engram: reconsolidation and the lingering consolidation hypothesis. Neuron. 2004; 44:93–100. [PubMed: 15450162]
9. Sara SJ. Retrieval and reconsolidation: Toward a neurobiology of remembering. Learn Mem. 2000; 7:73–84. [PubMed: 10753974]
11. Dudai, Y. Post-activation state: a critical rite of passage of memories. In: Bontempi, B., et al., editors. Memories: Molecules and Circuits. Springer-Verlag; 2007. p. 69-82.
12. Walker MP, et al. Dissociable stages of human memory consolidation and reconsolidation. Nature. 2003; 425:616–620. [PubMed: 14534587]
13. Hupbach A, et al. Reconsolidation of episodic memories: A subtle reminder triggers integration of new information. Learn Mem. 2007; 14:47–53. [PubMed: 17202429]
14. Gordon WC, Feldman DT. Reactivation-induced interference in a short-term retention paradigm. Learn Motiv. 1978; 9:164–178.
15. Maroun M, Akirav I. Arousal and stress effects on consolidation and reconsolidation of recognition memory. Neuropsychopharmacology. 2008; 33:394–405. [PubMed: 17429409]
16. Wang XY, et al. Stress impairs reconsolidation of drug memory via glucocorticoid receptors in the basolateral amygdala. J Neurosci. 2008; 28:5602–5610. [PubMed: 18495894]
17. Dudai Y. The neurobiology of consolidations, or, how stable is the engram? Annu Rev Psychol. 2004; 55:51–86. [PubMed: 14744210]
18. Dudai Y. Reconsolidation: the advantage of being refocused. Curr Opin Neurobiol. 2006; 16:174– 178. [PubMed: 16563730]
19. Tronel S, et al. Linking new information to a reactivated memory requires consolidation and not reconsolidation mechanisms. PLoS Biol. 2005; 3:e293. [PubMed: 16104829]
The source is mentioned once here, but it is not at all clear that the entire discussion here is taken from the source, including all references to the literature.