Poster D5, Wednesday, August 21, 2019, 5:15 – 7:00 pm, Restaurant Hall
Spatiotemporal signatures of linguistic control mechanisms in bilingual and monolingual contexts.
Polina Timofeeva1, Lucia Amoruso1,2, Manuel Carreiras1,2,3;1Basque Center on Cognition, Brain and Language (BCBL), 2Ikerbasque, Basque Foundation for Science, 3University of the Basque Country UPV/EHU
An increasing number of people learn second and third languages to proficiently communicate on a daily basis. While extensive work has been conducted on how bilinguals control language selection and production [1-2], one question that remains unanswered is whether different linguistic control mechanisms subserve language and semantic category switching and if they follow the same time course. In order to address this issue, we compared switching processes under two different linguistic contexts, either requiring the alternation between languages or between semantic categories (nouns and verbs) within the same language. We recorded neuromagnetic signals with a 306-sensor Elekta Neuromag system while 20 balanced bilingual participants performed tasks in which they had to produce words in different contexts. In one context, they had to switch between languages (Spanish/Basque). In the other, they had to switch between producing nouns or verbs in a single language (Spanish or Basque). As in classical switching paradigms, there were two conditions: switch (i.e., language or category change between trials) and repeat condition (i.e., 2 consecutive stimuli presented in the same language or category). Conditions were randomized while tasks were blocked. We used event-related field (ERF) analysis to examine which components contributed to control processing within the two contexts. Differences between conditions were assessed using cluster-based permutation tests. The analysis revealed significant power modulations in M200 and M400 components, with the switching condition showing power decreases as compared to the repetition one, either in language or category switching. Interestingly, while the language switching effect was distributed over right sensors, the category switching effect was distributed over left sensors. Overall, our results point to the existence of different control mechanisms devoted to between-language and within-language switching in high-proficient bilinguals [3-4]. While both mechanisms displayed a similar time-course, their lateralization differed, with language switching involving the right hemisphere and semantic switching the left one thus suggesting the recruitment of distinct cortical networks depending on the linguistic context. References [1] H.Liu, S.Rossi, H.Zhou, and B.Chen (2014). Electrophysiological Evidence for Domain-General Inhibitory Control during Bilingual Language Switching. PLoS One, 9(10). [2] E.Blanco-Elorrieta, and L Pylkkänen (2016). Bilingual Language Control in Perception versus Action: MEG Reveals Comprehension Control Mechanisms in Anterior Cingulate Cortex and Domain-General Control of Production in Dorsolateral Prefrontal Cortex. Journal of Neuroscience, 36(2). [3] J.Sierpowska, A.Gabarrós, P.Ripollés, M.Juncadella, S.Castañer, Á.Camins, G.Plans, and A.Rodríguez-Fornells (2013). Intraoperative electrical stimulation of language switching in two bilingual patients. Neuropsychologia 51. [4] S.Moritz-Gasser and H.Duffau. (2009). Cognitive processes and neural basis of language switching: Proposal of a new model. Neuroreport 20.
Themes: Control, Selection, and Executive Processes, Multilingualism
Method: Electrophysiology (MEG/EEG/ECOG)