The depth of semantic processing modulates cross-language pattern similarity in Chinese-English bilinguals

Previous studies have investigated factors related to the degree of cross-language overlap in brain activations in bilinguals/multilinguals. However, it is still unclear whether and how the depth of semantic processing (a critical task-related factor) affects the neural pattern similarity between native and second languages. To address this question, 26 Chinese-English bilinguals were scanned with fMRI while performing a word naming task (i.e., a task with shallow semantic processing) and a semantic judgment task (i.e., a task with deep semantic processing) in both native and second languages. Based on three sets of representational similarity analysis (whole brain, ROI-based, and within-language vs. cross-language semantic representation), we found that select regions in the reading brain network showed higher cross-language pattern similarity and higher cross-language semantic representations during deep semantic processing than during shallow semantic processing. These results suggest that compared to shallow semantic processing, deep semantic processing may lead to greater language-independent processing (i.e., cross-language semantic representation) and cross-language pattern similarity, and provide direct quantitative neuroimaging evidence for cognitive models of bilingual lexical memory.

Automated summary

Previous studies have explored factors influencing cross-language overlap in bilinguals/multilinguals' brain activations. However, it remains uncertain how the depth of semantic processing affects the similarity of neural patterns between native and second languages. To address this, Chinese-English bilinguals underwent fMRI scans while performing shallow and deep semantic processing tasks in their native and second languages. Results from representational similarity analysis indicated that deep semantic processing led to higher cross-language pattern similarity and semantic representation in select regions of the reading brain network, compared to shallow semantic processing.