Abstracts
Résumé
Les mécanismes cellulaires et moléculaires de l’acquisition et de la mémorisation sont extrêmement complexes et mal compris. Ceux de l’oubli le sont moins encore, mais plusieurs théories ont été formulées pour tenter d’en expliquer les causes et les origines. De récentes découvertes ont révélé que l’oubli a des mécanismes et une base anatomique spécifiques, distincts de ceux de l’apprentissage et de la mémoire, mais faisant intervenir des protéines communes. Ils semblent dépendre en grande partie des protéine phosphatases, des enzymes abondantes dans le cerveau et capables de contrôler de nombreuses cibles biochimiques dans les cellules nerveuses. La formation de la mémoire, quant à elle, est assurée surtout par des protéines kinases. Mémoire et oubli sont en fait régis par un équilibre entre phosphatases et kinases qui détermine l’efficacité de l’apprentissage et la persistance des souvenirs. Cet article présente un bref aperçu des connaissances actuelles sur l’oubli. Elle récapitule ses principales caractéristiques et résume certaines des découvertes les plus récentes faites sur ses mécanismes potentiels.
Summary
The cellular and molecular mechanisms of learning and memory are extremely complex and not well understood. The mechanisms of forgetting are even further more unclear, but several theories have been formulated to explain their cause and origin. Forgeting has recently been revealed to recruit specific mechanisms and anatomical basis which some components are distinct from those of learning and memory. Forgetting appears to depend essentially on protein phosphatases, enzymes highly abundant in the brain that are able to regulate numerous biochemical targets in neurons. The formation of memory by contrast depends on protein kinases. Memory and forgeting are indeed reciprocally controlled by a balance between kinases et phosphatases that determines the efficacy of learning and the persistence of memory. This review provides a brief account of the main features of forgetting and a summary of the most recent findings on its potential mechanisms.
Appendices
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