Increased world knowledge in older adults does not prevent decline in world knowledge comprehension: An ERP study

Area of Science:

• Cognitive Neuroscience
• Psychology of Aging

Background:

• World knowledge generally increases with age.
• Semantic processing abilities tend to decline in older adults.
• The interplay between accumulated world knowledge and declining semantic processing in comprehension remains unclear.

Purpose of the Study:

• To investigate whether increased world knowledge compensates for age-related decline in semantic processing.
• To examine how older and younger adults process semantic versus world knowledge violations.
• To explore the neural underpinnings of sentence comprehension in aging.

Main Methods:

• Electroencephalography (EEG) data collected from 43 older and 43 younger adults.
• Participants read sentences with semantic violations and world knowledge violations.
• Analysis focused on the N400 event-related potential component.

Main Results:

• Older adults showed reduced N400 amplitude and delayed latency for both semantic and world knowledge violations compared to younger adults.
• A significant interaction indicated that older adults had a smaller N400 for world knowledge violations than semantic violations in posterior regions.
• N400 differences correlated negatively with vocabulary scores, suggesting a link to semantic capacity.

Conclusions:

• Age-related increases in world knowledge do not enhance comprehension of world knowledge-violating sentences in older adults.
• Declining semantic processing significantly impacts older adults' ability to integrate world knowledge.
• Vocabulary knowledge may play a role in mitigating comprehension deficits related to world knowledge integration.