Memory updating in crabs: adding opposite information during reconsolidation phase

MARTÍN KLAPPENBACH; LAURA KACZER; FERNANDO LOCATELLI

Congreso; XXXII Congreso Anual de la Sociedad Argentina de Investigación en Neurociencias; 2017

Reconsolidation theory postulates that, oncereactivated, a previously stable memory becomes labile, suffering then aprocess of stabilization named reconsolidation. It has been suggested thatreconsolidation might enable memories to be modified or updated. This updatecould allow animals to change the content of the memory, and this permits themto adapt their behavior to a changing word. Although memory updating is a phenomenon thathas been studied in diverse species, it is not very clear what happen whenanimals receive a stimulus that contradicts a prediction generated by aprevious experience. A recent work performed in rats shows that a fear memoryis weakened if animals receive a positive stimulus in a learned aversive context.In the present study we train crabs in an aversive or appetitive paradigm and then,when this memory is labile, animals receive the stimulus of opposite valence. Wedemonstrated that, despite the strength of the stimulus that animals receive, theformer learning is not occluded and also the memory associated with the newstimulus is revealed. Taking in mind that when crabs face two opposite stimuliat the same time they build two parallel memories, an open question of ourresults is, if under these conditions, animals are forming two memories or on the contrary, new information is added to the originaltrace.