Contrasting dynamics of memory consolidation for novel word forms and meanings revealed by behavioraland neurophysiological markers

KACZER LAURA; BAVASSI LUZ; FERNANDEZ RODRIGO SEBASTIAN; PETRONI AGUSTÍN; LAURINO JULIETA; DEGIORGI SOFÍA; HOCHMAN EITHAN; FORCATO CECILIA; PEDREIRA MARÍA EUGENIA

NEUROPSYCHOLOGIA

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2018

0028-3932

Learning novel words is a challenging process for our memory systems; we must be able to recall new word forms and meanings in order to communicate. However, the dynamics of the word memory formation is still unclear. Here, we addressed the temporal profileof two key cognitive markersof memory consolidation in the domain of word learning:i) the susceptibility of recently learned novel words to memory interference; ii) theirlexical integration using a semantic judgment task while recording the ERPs responses.Young adults acquired a set of novel picture-label-meaning associations. In a first experiment, we performed a temporal gradient of retroactive interference (5min, 30 min, 4h and 24h) and evaluated the memory retention 48h after learning. In a second experiment, we studied the dynamics of the integration of these novel words, by measuring theirN400 modulation when preceded by semantically related words, at 30 min or 48 h after learning. Our results showed that the word-formmemory was affected by the interference treatment when it was presented 5 min after learning, but not at later times. On the other hand, only 48h after learning it was possible to observe a neurophysiological index of semantic-priming (reduced N400 response). These results point to the existence of two contrasting processes that help to build the memory for word forms and meanings.A rapid mechanism would enable word learning while mitigating forgetting, while a slow consolidation would allow the novel meanings to be integrated into previous semantic networks.