Decreased activity with increased background network efficiency in amnestic MCI during a visuospatial working memory...

Area of Science:

• Neuroscience
• Cognitive Science
• Medical Imaging

Background:

• Working memory impairment is a known issue in amnestic mild cognitive impairment (aMCI).
• The underlying neurophysiological mechanisms of this deficit remain unclear.
• Understanding these mechanisms is crucial for diagnosing and managing aMCI.

Purpose of the Study:

• To investigate abnormal brain activity during working memory tasks in aMCI patients.
• To explore the reorganization of brain networks supporting working memory in aMCI.
• To identify the neurophysiological basis of working memory deficits in aMCI.

Main Methods:

• Event-related functional magnetic resonance imaging (fMRI) was employed.
• A visuospatial working memory task with varying recognition difficulty was administered.
• Task-related brain activations and background network efficiency were analyzed in aMCI patients and controls.

Main Results:

• aMCI patients exhibited decreased frontal and visual cortex activity during encoding compared to controls.
• Reduced activity in frontal, parietal, and visual regions was observed during recognition in aMCI patients.
• The background network in aMCI patients showed increased local efficiency, suggesting compensatory effort.

Conclusions:

• aMCI is associated with impaired encoding and recognition in visuospatial working memory.
• Increased local efficiency in the background network may indicate compensatory mechanisms in aMCI.
• This research provides insights into the neural underpinnings of working memory deficits and compensatory strategies in aMCI.