Investigating the Bilingual Aging Lexicon: A Network Analysis of Word Associations in Chinese-English Bilinguals

The present study examines the bilingual aging lexicon by comparing word association networks across four age groups of Chinese-English bilingual adults. Adopting network analysis with breadth-first search-based sampling, results showed that in L1 (Chinese) networks, global connectivity increases from early to mid-adulthood, accompanied by reduced local clustering and enhanced global efficiency; the network remains relatively stable through midlife, followed by declining efficiency and progressively pronounced modular structure in late adulthood. The L2 (English) networks mirror L1 developmental trends in early and mid-adulthood but with substantially larger shifts; throughout adulthood, L2 exhibits lower global and local connectivity and weaker modularity compared to L1. These findings reveal distinct developmental trajectories for L1 and L2 semantic networks in bilinguals, underscoring greater structural stability in the dominant language (L1) across adulthood relative to the nondominant language (L2). This L1-L2 asymmetry points to differential impacts of aging on bilingual lexical organization. Results are discussed in relation to compensatory mechanisms and enrichment accounts of cognitive aging.