Retrieval of retrained and reconsolidated memories are associated with a distinct neural network
BAVASSI L; FORCATO C; FERNANDEZ R; DE PINO G; PEDREIRA ME; VILLARREAL MF
Springer Nature Publishing AG
Consolidated memories can persist from a single day to years, and persistence is improved byretraining or retrieval-mediated plasticity. One retrieval-based way to strengthen memory is thereconsolidation process. Strengthening occurs simply by the presentation of specific cues associatedwith the original learning. This enhancement function has a fundamental role in the maintenance ofmemory relevance in animals everyday life. In the present study, we made a step forward in theidentification of brain correlates imprinted by the reconsolidation process studying the long-termneural consequences when the strengthened memory is stable again. To reach such a goal, wecompared the retention of paired-associate memories that went through retraining process or werelabilizated-reconsolidated. Using functional magnetic resonance imaging (fMRI), we studied thespecific areas activated during retrieval and analyzed the functional connectivity of the whole brainassociated with the event-related design. We used Graph Theory tools to analyze the global featuresof the network. We show that reconsolidated memories imprint a more locally efficient network thatis better at exchanging information, compared with memories that were retrained or untreated. For thefirst time, we report a method to elucidate the neural footprints associated with a relevant function ofmemory reconsolidation.