Alpha and beta dynamics support task-based word production

Poster Session B - Sunday, April 14, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Ioanna Zioga^1,2 (ioanna.zioga@donders.ru.nl), Hugo Weissbart¹, Ying Joey Zhou^1,3, Saskia Haegens^1,4,5, Andrea E. Martin^1,2; ¹Donders Centre for Cognitive Neuroimaging, Nijmegen, the Netherlands, ²Max Planck Institute for Psycholinguistics, Nijmegen, the Netherlands, ³Oxford Centre for Human Brain Activity, Oxford, UK, ⁴Columbia University, New York, USA, ⁵New York State Psychiatric Institute, New York, USA

Brain oscillations support a wide range of linguistic processes, from lexical retrieval to attention and prediction on word- and sentence-level processing. However, little is known about the role of brain rhythms in task-based word production, which is key to semantic cognition. We constructed a novel paradigm in which participants produced an alternative exemplar or a feature of a target word embedded in spoken sentences (e.g., for the word tuna an exemplar from the same category —seafood— would be shrimp, and a feature would be pink). A visual cue indicated the task —exemplar or feature. Magnetoencephalographic data were analyzed during thinking, before participants verbalized their answer. We found that, compared to exemplars, participants were slower, gave more variable and more semantically distant (from the target word) answers, suggestive of increased association strength for exemplars. Word frequency was positively correlated with semantic distance for features, while higher semantic distance was associated with more original answers for exemplars, reflective of differential lexical processing between tasks. Furthermore, linear mixed models revealed that alpha-beta power positively correlated with reaction times, in line with the role of those rhythms in facilitating task performance by regulating inhibition. Critically, semantic distance negatively correlated with alpha and beta power in left-hemispheric regions, potentially associated with cognitive control, showing however a differential spatiotemporal pattern for features compared to exemplars. We conclude that the generation of semantic associations relies on top-down mechanisms reflected in alpha and beta dynamics, providing evidence for the role of those oscillations in word production.

Topic Area: LANGUAGE: Semantic