Differential neurophysiological correlates of retrieval of consolidated and reconsolidated memories in humans: An ERP and pupillometry study
CAMPOS-ARTEAGA, G.; FORCATO, C.; WAINSTEIN, G.; LAGOS, R.; PALACIOS-GARCÍA, I.; ARTIGAS, C.; MORALES, R.; PEDREIRA, M.E.; RODRÍGUEZ, E.
NEUROBIOLOGY OF LEARNING AND MEMORY
ACADEMIC PRESS INC ELSEVIER SCIENCE
Año: 2020 vol. 174
Consolidated memories can return to a labile state if they are reactivated byunpredictable reminders. To persist, active memories must be re-stabilized through aprocess known as reconsolidation. Although there is consistent behavioral evidenceabout this process in humans, the retrieval process of reconsolidated memories remainspoorly understood. In this context, one fundamental question is whether the same ordifferent neurophysiological mechanisms are involved in retrieval of consolidated andreconsolidated memories. Because it has been demonstrated that the exposure to thereconsolidation process may restructure and strengthen memories, we hypothesizeddistinct neurophysiological patterns during retrieval of reconsolidated memories. Inaddition, we hypothesized that interfering with the reconsolidation process using a newlearning can prevent these neurophysiological changes. To test it, consolidated,reconsolidated and declarative memories whose reconsolidation process was interfered(i.e., picture-word pairs) were evaluated in humans in an old/new associative recall taskwhile the brain activity and the pupillary response were recorded usingelectroencephalography and eyetracking. Our results showed that retrieval ofreconsolidated memories elicits specific patterns of brain activation, characterized by anearlier peak latency and a smaller magnitude of the left parietal ERP old/new effectcompared to memories that were only consolidated or whose reconsolidation processwas interfered by a new learning. Moreover, our results demonstrated that only retrievalof reconsolidated memories is associated with a late reversed mid-frontal effect in a 600-690 time window. Complementarily, memories that were reactivated showed an earlierpeak latency of the pupil old/new effect compared to non-reactivated memories. Thesefindings support the idea that reconsolidation has an important impact in how memoriesare retrieved in the future, showing that retrieval of reconsolidated memories is partiallysupported by specific brain mechanisms.