Aversive and appetitive memories are simultaneously formed alfter a single training session in the crab Neohelice

MARTÍN KLAPPENBACH; FERNANDO LOCATELLI

Congreso; XXX Congreso de la Sociedad Argentina de Neurociencias; 2015

Sociedad Argentina de Neurociencias

Unlike experimentally controlled situations, animals in nature might be exposed tocontradictory information. Situations or places might simultaneously predict desiredand undesired consequences. However, at some point the situation has to becategorized as appetitive or aversive, in order to decide if repeat or avoid it in thefuture. How contradictory information is integrated and how it affects learning andmemory has not been yet extensively studied. In the present work we took advantageof the well described aversive and appetitive learning paradigms in the crab Neoheliceto explore learning after simultaneous appetitive and aversive experiences associatedto the same context. First, we found that two parallel memory traces are formed aftersimultaneous appetitive and aversive training. Second, we found that the probabilitiesto express no, one or both learned behaviors depend on the balance between therelative strength of the aversive and appetitive unconditioned stimuli, thus revealing amutual interference under certain conditions. Finally, we found that the mentionedinterferences do not occur during learning or memory formation, rather duringmemory retrieval. These results suggest that both memories could be actually availableto be retrieved upon presentation of the conditioned stimulus, but the access ofmemory to behavior might be modulated based on specific demands at the momentof retrieval.