Dynamic neuroplasticity of language networks: The intersection of bilingualism and epilepsy

• 成果类型: Article
• 署名作者: Stasenko, Alena; Kaestner, Erik; Schadler, Adam J.; Reyes, Anny; Urbanic, Clare; Helm, Jonathan L.; Saldana, Daniel; Carollo-Duprey, Giselle; Polczynska, Monika; Benjamin, Christopher; Sepeta, Leigh N.; Gollan, Tamar H.; Cavanagh, Lucia; McDonald, Carrie R.
• 署名单位: University of California System; University of California San Diego; University of California System; University of California San Diego; Cleveland Clinic Foundation; California State University System; San Diego State University; Harvard University; Harvard University Medical Affiliates; Massachusetts General Hospital; California Lutheran University; University of California System; University of California Los Angeles; University of British Columbia; Children's National Health System; University of California System; University of California San Diego
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-12434
• DOI: 10.1073/pnas.2422742122
• 发表日期: 2025-07-22
• 关键词: native language; proficient bilinguals; neural differences; brain structure; lateralization; acquisition; AGE; fmri; english; REPRESENTATION

摘要

Are bilingual language networks flexible enough to dynamically adapt to neurological insult? We examined language lateralization in 24 bilingual and 46 monolingual adults with temporal lobe epilepsy using functional MRI. In a group of primarily early sequential bilingual patients, the first acquired language (L1) showed more bilateral lateralization than in monolingual patients, with no effect of seizure onset laterality. In contrast, the second- acquired language (L2) was more bilateral in the presence of left hemisphere epilepsy and more left- lateralized in right hemisphere epilepsy. Most notably, in left hemisphere epilepsy, seizure onset closer to L2 acquisition was associated with more right- lateralized L2 representation. These findings suggest a compensatory process in which L2 networks strengthen in the hemisphere opposite the seizure focus, potentially reflecting neural adaptation in early bilingualism. Conversely, L1 appears to have less dynamic reorganization in response to neurological insult. Together, these findings highlight the importance of timing in both language experience and neurological stress in shaping language network organization. They support the view that the bilingual brain is not simply the sum of two monolingual systems, but a dynamic and unique system marked by high interindividual variability, in which divergence between languages may emerge under certain experience- and context- dependent conditions.