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

LUZ BAVASSI; SOFÍA DEGIORGI; MARÍA E. PEDREIRA; LUZ BAVASSI; JULIETA LAURINO; SOFÍA DEGIORGI; RODRIGO S. FERNÁNDEZ; MARÍA E. PEDREIRA; CECILIA FORCATO; JULIETA LAURINO; RODRIGO S. FERNÁNDEZ; CECILIA FORCATO; LAURA KACZER; AGUSTÍN PETRONI; EITHAN HOCHMAN; LAURA KACZER; AGUSTÍN PETRONI; EITHAN HOCHMAN

NEUROPSYCHOLOGIA

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2018 p. 472 - 482

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 profile of two key cognitive markers of memory consolidation in the domain of word learning: i) the susceptibility of recently learned novel words to memory interference; ii) their lexical 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 (5 min, 30 min, 4 h and 24 h) and evaluated the memory retention 48 h after learning. In a second experiment, we studied the dynamics of the integration of these novel words, by measuring their N400 modulation when preceded by semantically related words, at 30 min or 48 h after learning. Our results showed that the word-form memory was affected by the interference treatment when it was presented 5 min after learning, but not at later times. On the other hand, only 48 h 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.