Parallel memory traces are built after an experience containing aversive and appetitive components in the crab Neohelice

NALLY, AYELÉN; LOCATELLI, FERNANDO FEDERICO; KLAPPENBACH, MARTÍN

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA

NATL ACAD SCIENCES

Año: 2017 vol. 114

0027-8424

The neurobiology of learning and memory has been mainly studied by focusing on pure aversive or appetitive experiences. Here, we challenged this approach considering that real-life stimuli come normally associated with competing aversive and appetitive consequences and that interaction between conflicting information must be intrinsic part of the memory processes. We used Neohelice crabs, taking advantage of two well-described appetitive and aversive learning paradigms and combining them in a single training session to evaluate how this affects memory. We found that crabs build separate appetitive and aversive memories that compete during retrieval but not during acquisition. Which memory prevails depends on the balance between the strength of the unconditioned stimuli and on the motivational state of the animals. The results indicate that after a mix experience with appetitive and aversive consequences, parallel memories are established in a way that appetitive and aversive information is stored to be retrieved in an opportunistic manner.