Effects of Working Memory Capacity and Noise Placement on Passive Sentence Processing in Elderly Adults: An Eye-Tracking Study

Abstract

Objectives: The purpose of this study was to investigate the effects of working-memory (WM) capacity on age-related changes in abilities to comprehend incomplete passive sentences using eye tracking. Methods: A total of 45 individuals participated in the study. The incomplete sentences were made by replacing dative case makers or verbs with white noise. A composite measure of WM scores was used as an index of WM capacity. Results: The elderly group and the lower WM group showed worse performance in accuracy and response time under the both noise conditions. All groups showed worse performance under the verb noise conditions in accuracy and response time. In accuracy, a two-way interaction between the age groups and the WM groups was significant. There was a correlation between the noise locations and the age groups in response time. In target advantage ratio (TA), there was a correlation between the regions and the age groups under the both conditions. Moreover, the main effect of the region was significant under the verb noise. Conclusion: Ageing reduces the ability of sentence processing and the sentences without verbs were more difficult to process for all groups. Also, the WM capacity can affect sentence processing and the affect increases with ageing. TA results showed that elderly adults use an inefficient strategy when dealing with incomplete passive-sentences, affected by reduced cognitive function due to ageing. Also, TA results suggested that WM capacity plays different roles in online and offline sentence processing.