Even though older adults are known to have difficulty at language processing when a secondary task has to be performed simultaneously, few studies have addressed how older adults process language in dual-task demands when linguistic load is systematically varied. Here, we manipulated surprisal, an information theoretic measure that quantifies the amount of new information conveyed by a word, to investigate how linguistic load affects younger and older adults during early and late stages of sentence processing under conditions when attention is split between two tasks. In high-surprisal sentences, target words were implausible and mismatched with semantic expectancies based on context, thereby causing integration difficulty. Participants performed semantic meaningfulness judgments on sentences that were presented in isolation (single task) or while performing a secondary tracking task (dual task). Cognitive load was measured by means of pupillometry. Mixed-effects models were fit to the data, showing the following: (a) During the dual task, younger but not older adults demonstrated early sensitivity to surprisal (higher levels of cognitive load, indexed by pupil size) as sentences were heard online; (b) Older adults showed no immediate reaction to surprisal, but a delayed response, where their meaningfulness judgments to high-surprisal words remained stable in accuracy, while secondary tracking performance declined. Findings are discussed in relation to age-related trade-offs in dual tasking and differences in the allocation of attentional resources during language processing. Collectively, our data show that higher linguistic load leads to task trade-offs in older adults and differently affects the time course of online language processing in aging. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Download full-text PDF

Source
http://dx.doi.org/10.1037/pag0000316DOI Listing

Publication Analysis

Top Keywords

older adults
28
language processing
16
linguistic load
12
age-related trade-offs
8
younger older
8
meaningfulness judgments
8
secondary tracking
8
dual task
8
cognitive load
8
older
7

Similar Publications

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!