Poster Session C, Sunday, March 24, 5:00 – 7:00 pm, Pacific Concourse
Electrophysiological correlates of auditory discourse processing in bilinguals across the lifespan
Angela Grant1,2, P. Tristin Best1, Natalie Phillips1,2; 1Concordia University, 2Centre for Research on Brain, Language, and Music
Our study examines auditory discourse comprehension in highly proficient English/French bilinguals. We compare a capacity view of language comprehension, which predicts reduced sensitivity to discourse compared to lexical cues in the second language (L2) due to increasing working memory demands, with the noisy channel model, which predicts the reverse. We tested young (18-35 yrs; n=32) and older (60+ yrs; currently n=7) bilinguals, as increasing age is associated with declines in working memory. The two groups are matched on education and the older adults (OAs) were screened for normal vision and hearing. The OA performance on the operation span task is both lower (M=69.4%) and more variable (SD=27.5%) than younger adults’ (YA; M=82%, SD=16%). Our ERP paradigm uses three-sentence stories with prime and target words in the final sentence whose lexical association is manipulated, as is the congruence of the target with the preceding discourse. For YAs, we found that the N400 effect was sensitive to discourse congruence, but was qualified by an interaction such that the effect of discourse congruence was larger and more widespread regardless of lexical association in the L2, whereas the topography of the L1 effect was sensitive to lexical association. For OAs, we also observe a discourse congruence effect, which is later (700ms) compared to the young adults and limited to the L1. The differential sensitivity to L2 discourse cues with age provides partial support for both models, indicating a need for a more nuanced view of each that accounts for age-related changes in cognition.
Topic Area: LANGUAGE: Development & aging