Search Abstracts | Symposia | Slide Sessions | Poster Sessions
Typological similarity between languages modulates the neural mechanisms of selective attention in bilinguals
Poster Session F, Friday, October 2, 2:45 - 4:45 pm, Wangari Maathai
Jingkang Wang1, Andrea Olguin1, Mirjana Bozic1; 1University of Cambridge
Introduction: Bilingualism has been shown to modulate neural mechanisms of selective attention, due to the constant need to select the target language and inhibit the non-target one. Compared to monolinguals, whose neural encoding of attended speech increases as the interference becomes stronger, attentional encoding remains constant across different types of interference in bilinguals (Olguin et al., 2019). However, relevant studies mainly compare monolinguals and bilinguals speaking similar European languages, while the effect of the typological similarity between bilinguals’ L1 and L2 on attentional mechanisms is under-tested. It is possible that more distant languages are easier to distinguish during language selection, compete less and impose smaller additional cognitive demands, thus triggering less neural adaptions compared to similar languages. The current study probed the impact of typological similarity of bilinguals’ languages on auditory selective attention mechanisms, by comparing monolinguals and bilinguals speaking different language pairs. Methods: Data from 30 early proficient Chinese-English bilinguals were compared to the existing data for early Spanish-English and Dutch-English bilinguals (Olguin et al., 2019), who speak more similar languages, and English monolinguals (Olguin et al., 2018). Using the same dichotic listening design, participants attended to a narrative in their native language in one ear, while simultaneously ignoring competing streams in the other ear. Four conditions were generated by manipulating the type/intelligibility of interference: (1). Single talker (No interference), (2). Native-Musical Rain (the interference closely matches acoustic properties of speech but does not elicit linguistic percept), (3). Native-Unknown (the interference is a narrative in a language unknown to listeners), (4). Native-Native (the interference is also a narrative in listeners’ native language, creating the strongest distraction). Brain activity was recorded by a 128-channel EEG system and cross-correlated with speech envelopes extracted from the attended and unattended stimuli. Using multivariate Representational Similarity Analysis (RSA), activation patterns of Chinese-English bilinguals were then directly compared to data from Spanish-English bilinguals, Dutch-English bilinguals and English monolinguals. Results: Chinese-English bilinguals showed significantly stronger neural encoding of attended than of unattended streams across all conditions. Their attentional encoding increased as the distractor changed from non-linguistic (Musical Rain) to linguistic (narratives) but then remained constant across linguistic conditions (Native-Unknown vs. Native-Native), replicating aspects of the existing data (Olguin et al., 2018; 2019). RSA suggested that, of all three bilingual groups, the overall patterns of neural encoding in Chinese-English bilinguals were the closest to those of monolinguals, with their encoding patterns across conditions not significantly differentiating from English monolinguals in most of time windows tested. Conclusion: Taken together, we found that the neural mechanisms of auditory selective attention are generally modified by bilingualism, and that this modulation is further shaped by the typological similarity between bilinguals’ L1 and L2 - with larger distance between languages leading to significantly less modulation and a more monolingual-like pattern of neural encoding.
Topic Areas: Multilingualism, Control, Selection, and Executive Processes