Bilingualism Protects Domain-Specific Cognitive Function in Mandarin-Speaking Older Adults

ObjectivesThis study examined whether bilingualism is associated with episodic memory (EM) and executive function (EF) in older Mandarin-speaking adults and whether associations differ by clinical diagnosis. Methods189 Mandarin-speaking older adults completed Mandarin-administered neuropsychological testing, brain MRI, and clinical diagnosis. English proficiency test was administered to determine whether they were bilinguals or monolinguals. Sensitivity analyses were conducted in an education-matched subgroup (16 years). ResultsBilingualism was associated with higher EF, with a significant bilingualism x diagnosis interaction indicating larger bilingual advantages among cognitively impaired participants. However, bilingualism was not associated with EM. Findings were preserved in education-matched analysis. ConclusionsResults support a domain-specific association between bilingualism and executive function in later life, consistent with cognitive maintenance mechanisms preferentially supporting executive processes rather than global protection.