Effects of Age and Working Memory Load on Syntactic Processing: An Event-Related Potential Study

Area of Science:

• Neuroscience
• Cognitive Psychology
• Linguistics

Background:

• Aging is associated with cognitive decline, particularly in working memory (WM), potentially impacting language comprehension.
• Increased WM demands can negatively affect sentence processing performance in older adults.

Purpose of the Study:

• To investigate how increased working memory load affects syntactic processing in older adults compared to younger adults.
• To examine the neural correlates of sentence processing difficulties in aging using event-related potentials (ERPs).

Main Methods:

• Collected ERPs from young and older adults reading sentences with varying gender agreement and WM load (distance between noun and adjective).
• Participants detected grammatical errors to assess behavioral performance (accuracy and reaction time).

Main Results:

• Older adults exhibited longer reaction times than younger adults, irrespective of WM load.
• ERP analysis revealed smaller LMAN, P600a, and P600b effects in older adults with increased WM load.
• These ERP differences suggest difficulties in morpho-syntactic processing and constituent mapping under higher cognitive demand.

Conclusions:

• Increased WM load reveals subtle syntactic processing deficits in older adults, not evident in behavioral accuracy but reflected in ERP patterns.
• ERP findings indicate challenges in integrating sentence constituents and processing grammatical information when cognitive load is high in aging.
• The study highlights the sensitivity of ERPs in detecting age-related cognitive changes in language processing that may not be apparent through behavioral measures alone.