Presentation
Search Abstracts | Symposia | Slide Sessions | Poster Sessions | Poster Slams
Subcortical Volume is Related to Early Learning of a Second Language
Poster E71 in Poster Session E, Saturday, October 8, 3:15 - 5:00 pm EDT, Millennium Hall
Yinan Xu1, My V.H. Nguyen1, Arturo E. Hernandez1; 1University of Houston
The multilingual brain implements mechanisms that serve to select the appropriate language depending on the situational communicative environment. Engaging these mechanisms on a regular basis has been shown to have effects on structural adaptations of subcortical brain regions that are key for language control. Existing literature on bilingual-induced brain structural adaptations has found that volume in a variety of areas including the caudate nuclei, putamen, thalami, accumbens, as well as the cerebellum is linked to bilingual language experience. The current study used MRI data combined from 8 previous studies, consisting of 215 Spanish-English bilinguals and 145 English monolinguals. Language skills were assessed using several measures, including the Boston Naming Test (BNT; Goodglass et al., 1983) and/or the Woodcock-Muñoz Language Survey – Revised (WLS-R) picture vocabulary subtest along with either the passage comprehension subtest or listening comprehension subtest (Woodcock et al., 2010). A total measure of language skill was calculated as an average of proportion correct across different tests. Subcortical volume was compared between bilinguals and monolinguals, as well as correlated with language proficiency in all participants. Across the whole sample, English proficiency was positively related to subcortical volume in the right thalamus and the left nucleus accumbens after controlling for socioeconomic status (FDR corrected at p < .05). There was no difference between bilinguals and monolinguals in subcortical volume. Additional analyses were run within each group of participants. Notably, English proficiency, but not Spanish proficiency, and English age of acquisition positively correlated with the volume of the right thalamus and left nucleus accumbens in bilinguals; however, English proficiency was uncorrelated with subcortical volume in monolinguals. The results showed a combined effect of age of acquisition and English proficiency in volume adaptation in right thalamus and left nucleus accumbens in bilinguals. These findings are in line with existing literature on the dynamic volume adaptation of these brain regions on bilingual experiences. Studies have shown that the nucleus accumbens has been implicated in active language selection and processing (Deluca et al., 2019). In addition, the thalamus, connected with the Basal Ganglia via the dopaminergic system, was shown to be involved in language selection (Abutalebi & Green, 2016). It must be noted that the current study was unable to look at the separate effects of age of acquisition and English proficiency within our bilingual sample, as the two are highly correlated with each other and there was insufficient power to look at each effect separately. While the findings are intriguing, future studies are needed to better understand the unique contributions of AoA and proficiency on structure in these brain areas.
Topic Areas: Multilingualism, Development