Effects of age, working memory, and word order on passive-sentence comprehension: evidence from a verb-final language

Background: The purpose of the current study was to investigate the effects of working-memory (WM) capacity on age-related changes in abilities to comprehend passive sentences when the word order was systematically manipulated. Methods: A total of 134 individuals participated in the study. The sentence-comprehension task consisted of the canonical and non-canonical word-order conditions. A composite measure of WM scores was used as an index of WM capacity. Results: Participants exhibited worse performance on sentences with non-canonical word order than canonical word order. The two-way interaction between age and WM was significant, suggesting that WM effects were greater than age effects on the task. Conclusions: WM capacity effects on passive-sentence comprehension increased dramatically as people aged, suggesting that those who have larger WM capacity are less vulnerable to age-related changes in sentence-comprehension abilities. WM capacity may serve as a cognitive reserve associated with sentence-comprehension abilities for elderly adults.