Working memory and online syntactic processing in Alzheimer's disease: studies with auditory moving window...

Area of Science:

• Neuroscience
• Psycholinguistics
• Cognitive Psychology

Background:

• Dementia of the Alzheimer's type (DAT) is characterized by cognitive decline, including working memory impairments.
• The impact of reduced working memory on complex language processing, particularly syntactic comprehension, remains an area of active research.

Purpose of the Study:

• To investigate whether early-stage DAT patients exhibit deficits in online syntactic processing despite known working memory impairments.
• To determine if syntactic complexity differentially affects sentence comprehension and processing times in DAT patients compared to healthy controls.

Main Methods:

• Twenty patients with DAT and 20 healthy controls completed working memory tasks.
• Participants performed online auditory sentence comprehension tasks with varying syntactic complexity, measuring listening times and plausibility judgments.
• Listening times for sentence phrases and end-of-sentence judgment times were recorded.

Main Results:

• DAT patients demonstrated lower working memory scores and poorer plausibility judgments than controls.
• Both groups showed similar effects of syntactic structure on listening times, indicating preserved syntactic processing.
• Syntactic complexity did not disproportionately affect DAT patients' plausibility judgments or listening times compared to controls.
• Increased listening times at complex syntactic points did not correlate with working memory measures.

Conclusions:

• Early-stage DAT patients can assign syntactic structure and utilize it for meaning, even with reduced working memory.
• These findings support a dissociation within working memory, highlighting a specialization for syntactic processing.
• The study provides evidence for preserved language comprehension mechanisms in the early stages of Alzheimer's disease.