Dynamic working memory performance in individuals with single-domain amnestic mild cognitive impairment

Area of Science:

• Cognitive Neuroscience
• Gerontology
• Neurology

Background:

• Working memory (WM) deficits are noted in amnestic mild cognitive impairment (aMCI).
• It remains unclear if these WM issues are specific to multiple-domain aMCI subtypes.
• Executive functioning is often impaired in multiple-domain aMCI.

Purpose of the Study:

• To investigate working memory performance in single-domain aMCI.
• To compare WM in single-domain aMCI with healthy older adults.
• To assess the sensitivity of WM tasks in detecting early cognitive changes.

Main Methods:

• Working memory was assessed using the self-ordered pointing task (SOPT) and an n-back task.
• Participants included healthy older adults and individuals with single-domain aMCI.
• Performance metrics included errors, strategy development time, and discrimination accuracy.

Main Results:

• Single-domain aMCI patients made more SOPT errors and needed more time to strategize.
• No significant differences were found on 1-back and 2-back tasks between groups.
• The aMCI group exhibited poorer discrimination on the 3-back task.

Conclusions:

• Single-domain aMCI impacts working memory, particularly strategy formation and complex recall.
• Findings support the continuum hypothesis of MCI progression towards dementia.
• Standardized WM span tasks may lack sensitivity for subtle cognitive changes in early MCI.