Age did not affect word segmentation in younger or older Basque-Spanish bilinguals, suggesting "the stability of segmentation abilities across the adult lifespan", while L2 proficiency (and, minimally, language switching and fluid intelligence) shaped how bilinguals used multiple cues in L2 segmentation.
Age group (younger vs. older adults) did not affect word segmentation performance in either the L2 Basque or the native Basque group.
Proficiency modulated L2 Basque bilinguals' segmentation performance, with gains varying by the type of cues available in the sentence.
Frequency of language switch and fluid intelligence were associated with better overall performance, but explained very little variance.
Native Basque speakers benefited more than non-natives from lexico-semantic cues.
Native speakers benefited more than non-natives from morphosyntactic and phonological cues when targets were word-initial.
Different bilingual factors shape multiple-cue use in L2 segmentation, while age does not.
This study asked whether older adults are worse than younger adults at picking out individual words from continuous speech in a second language. Researchers tested 158 Spanish-speaking adults (younger and older) who had learned Basque as a second language, plus 63 native Basque speakers, using a task where listeners detected a speech sound in Basque sentences. The sentences differed in what clues were available: meaning, grammar, and sound patterns. Age made no difference to performance in either group. What mattered more for second-language learners was proficiency: more proficient people gained the most when sentences contained all types of clues, less when only grammar and sound clues were present, and least when only sound patterns were available. Frequently switching between languages and higher fluid intelligence were linked to slightly better performance, but their effects were very small. Native speakers made better use of meaning clues than non-natives, and of grammar and sound clues for sounds at the beginning of words. This research suggests that the ability to segment speech stays stable across adulthood, at least in bilinguals, and that language experience and skill shape how people use different clues more than age does. The findings come from one language pair (Basque and Spanish) and one task, so they may not generalize to all settings.
Fuente-García P, Villegas J, Zawiszewski A, de la Cruz-Pavía I. (2026). Word segmentation abilities across the adult lifespan: Evidence from younger and older adult bilinguals.. Cognition. https://doi.org/10.1016/j.cognition.2026.106743