A meta-analysis of language and cognition in the developing bilingual brain: From infancy to adolescence

Poster Session A - Saturday, April 13, 2024, 2:30 – 4:30 pm EDT, Sheraton Hall ABC

Kai Ian Leung¹ (kaiian.leung@mail.utoronto.ca), Lindsay Williams¹, Pascale Tremblay², Elizabeth Rochon¹, Monika Molnar¹; ¹University of Toronto, ²Université Laval

While the number of studies investigating the neural mechanisms of language and cognition in bilingual children is still few, it has been steadily growing. This systematic review and exploratory meta-analysis of functional magnetic resonance imaging (fMRI) and functional near-infrared spectroscopy (fNIRS) studies aimed to identify brain regions involved in bilingual children’s task-based language and cognition. We focused on peer-reviewed, primary articles that involved both bilingual and monolingual participants <18 years of age, reporting brain activations (fMRI: [x,y,z] coordinates) for language and/or cognitive tasks, and excluding literacy-related processes. A coordinate-based, exploratory meta-analysis of fMRI studies with activation likelihood estimation was used to examine the brain regions involved. However, fNIRS studies were too heterogeneous in their data reporting standards. Most fNIRS papers did not report sufficient statistical and methodological information for a meta-analysis. Out of the 27 studies that met inclusion criteria, six fMRI studies could be included in the exploratory meta-analysis. Our synthesis and meta-analyses suggest that: (1) young bilinguals’ neural correlates of language and cognition recruited classic language and control networks involving the frontal (prefrontal cortex, inferior frontal gyrus), parietal (inferior parietal lobule), temporal (superior temporal gyrus) cortices; (2) functional differences between bilinguals and monolinguals were identifiable through meta-analysis, notably in left inferior frontal gyrus Findings suggest bilingual children and adults share similar networks for language and cognition; however, more studies are needed to understand how bilingualism influences the brain's functional organization and lateralization depending on the bilingualism-related factors and level (e.g., speech segment, continuous speech) of processing.

Topic Area: LANGUAGE: Development & aging