Search Abstracts | Symposia | Slide Sessions | Poster Sessions
EEG-Based Investigation of Semantic Categorisation in Mandarin-English bilinguals
Poster Session E, Friday, October 2, 11:00 am - 1:00 pm, Wangari Maathai
This poster is part of the Sandbox Series.
Tobias Meeks1, Walter van Heuven1, Ruediger Thul1, Matias Ison1; 1University of Nottingham
Bilinguals activate the same concept across two different languages. Previous research investigated whether semantic representations are shared across language at semantic-conceptual levels. Audio particularly provides a useful mode of investigating this, given the dynamic unravelling of semantic information over time. Prior neuroimaging research identified language-invariant spatial (e.g. Buchweitz et al., 2012; van de Putte et al., 2017) and temporal (e.g. Correia et al., 2015; Cho et al., 2024) signatures associated with semantic processing, suggesting partially shared semantic representations across languages. ERP studies showed neural distinctions in monolinguals (Kiefer et al., 2001; Sitnikova et al., 2011) and bilinguals (Thierry & Wu, 2007) relating to semantic categorisation and access, especially within the N400 time window. Previous work generally focused on broad semantic contrasts, using large stimuli sets, limiting understanding of whether neural activity distinguishes semantic information at refined categorical levels. Additionally, research regarding the generalisability of these semantic distinctions across language is limited. The current study investigates whether EEG activity elicited by spoken words in Mandarin and English contains distinguishable information related to both superordinate and subordinate semantic categories in Mandarin-English bilinguals to uncover the extent to which semantic representations are distinguished within-language, and whether these differences are preserved across language. Mandarin and English are substantially distinct in their phonology and orthography, providing a strong comparison for the generalisability of semantic processing across language. Mandarin-English bilinguals completed an auditory semantic categorisation task while EEG was recorded, using a BioSemi 64-channel system. Participants listened to spoken words in Mandarin (L1) and English (L2) and categorised prompted words as “man-made” or “natural”. Each word belongs to one of four subordinate categories (“animal”, “fruit”, “instrument”, “clothing”), which are nested within superordinate categories (“man-made” and “natural”). Eight items were used in the study, each subordinate category consisting of two items. The experiment contained eight blocks per language. Each item was spoken by four speakers per language, with each of these variations being repeated twice in their respective language blocks. Containing multiple repetitions of each item reduces effects caused by the item’s acoustic representation, focusing more on its semantic information. Proficiency was measured using a language background questionnaire and LexTALE test (Lemhofer & Broersma, 2012). ERP analysis focused on N400 time window differences within and across category and language Preliminary analyses (N=16) focused on superordinate category differences, revealing significant N400 differences between English and Mandarin spoken words (t=2.473, p=0.0280). This effect was driven by “natural” words; L2 words elicited larger N400 amplitudes than their L1 translations. This pattern was not seen between “man-made” items. Within-language analyses revealed significant N400 differences between L1 superordinate categories (t=2.996, p=0.0103); “man-made” items elicit larger N400 amplitudes than “natural” stimuli. No effects were found in L2. Current findings suggest that semantic categorisations are partially distinguishable across languages, and at different levels, with L1 containing more refined N400 distinctions visible at the superordinate category-level. These findings suggest more refined neural categorisation at the superordinate level in a native language relative to a bilingual’s second language, hinting at differences in semantic-conceptual representations across language.
Topic Areas: Meaning: Lexical Semantics, Multilingualism