Protein synthesis subserves reconsolidation or extinction depending on reminder duration.
When learned associations are recalled from long-term memory stores by presentation of an unreinforced conditioned stimulus (CS), two processes are initiated. One, termed reconsolidation, re-activates the association between the conditioned and unconditioned stimuli and transfers it from a stable protein synthesis-independent form of storage to a more labile protein-dependent state. The other is an extinction process in which presentation of the CS alone degrades the association between CS and US. To address the mechanistic relationship between reconsolidation and extinction, we have used an invertebrate model of contextual memory, which involves an association between the learning context and a visual danger stimulus. Here, we show that re-exposure duration to the learning context acts as a switch guiding the memory course toward reconsolidation or extinction, each depending on protein synthesis. Manipulation of this variable allows findings of impaired extinction to be discriminated from those of disrupted reconsolidation.
Pedreira
María Eugenia
ME
Laboratorio de Neurobiología de la Memoria, Departamento de Fisiología y Biología Molecular, IFIBYNE-CONICET, Pabellón II, Facultad de Ciencias Exactas y Naturales (C1428EHA), Universidad de Buenos Aires, Buenos Aires, Argentina.
Maldonado
Héctor
H
D000818:Animals; D003386:Brachyura / Q000502:physiology*; D003213:Conditioning, Psychological; D003513:Cycloheximide / Q000494:pharmacology; D004924:Escape Reaction / Q000502:physiology; D007858:Learning / Q000502:physiology*; D008297:Male; D008568:Memory / Q000502:physiology*; D023421:Models, Animal; D014176:Protein Biosynthesis; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology; D014785:Vision, Ocular
D011500:Protein Synthesis Inhibitors; D003513:Cycloheximide