A BEHAVIORAL-TAGGING PERSPECTIVE OF SPACED LEARNING: ERKs1/2 KINASES PLAY A DUAL ROLE IN LTM FORMATION DURING A SPATIAL OBJECT-RECOGNITION TASK.

TINTORELLI, R; LOPES DA CUNHA, P; CORREA, J; BUDRIESI, P; H. VIOLA

Villa Carlos Paz

Congreso; Sociedad Argentina de Neurociencias; 2019

SAN

The superiority of spaced over massed learning is an established fact in the formation of long-term memories (LTM). Here we addressed the cellular processes and the temporal demands of this phenomenon, using a weak spatial object recognition (wSOR) training task, in which the animal acquired the information but not form LTM, registered 24hs after training. We observed SOR-LTM promotion when two identical wSOR training sessions were spaced by an inter-trial interval ranging from 15 minutes to 7 hours, consistently with spaced training. The promoting effect was dependent on neural activity and protein synthesis in the dorsal hippocampus. Based on the "behavioral tagging" hypothesis, which postulates that learning induces a neural tag that requires proteins to form LTM, we propose that retraining will mainly retag the sites initially labeled by the prior training. Thus, when weak, consecutive training sessions are experienced within an appropriate spacing, the intracellular mechanisms triggered by each session would add, thereby reaching the threshold for protein synthesis required for memory consolidation. In addition, our results suggest that ERKs1/2 kinases play a dual role in SOR-LTM formation after spaced learning, both inducing protein synthesis and setting the SOR learning-tag.