Altered Distant Synchronization of Background Network in Mild Cognitive Impairment during an Executive Function Task.

Area of Science:

• Neuroscience
• Cognitive Science
• Medical Imaging

Background:

• Mild cognitive impairment (MCI) is associated with executive function deficits.
• The background brain network's role in executive function in MCI remains understudied.
• Understanding task-evoked cognitive states is crucial for MCI research.

Purpose of the Study:

• To investigate background network synchronization during executive function tasks in MCI patients.
• To explore differences in functional connectivity (FC) and degree of centrality (DC) between MCI and normal control (NC) groups.
• To identify neural mechanisms underlying executive function impairments in MCI.

Main Methods:

• Utilized a hybrid delayed-match-to-sample task (DMST) to assess working memory, a key executive function.
• Employed degree of centrality (DC) to measure distant synchronization within the background network.
• Conducted seed-based correlation analysis to examine functional connectivity (FC) between specific brain regions.

Main Results:

• Significant group-by-cognitive-state interactions observed in the posterior cingulate cortex (PCC)/precuneus and right angular gyrus.
• Normal controls (NC) showed decreased long-range functional connectivity (FC) from rest to working memory state, while MCI patients did not.
• MCI patients exhibited a lack of efficient reorganization in brain network activity between rest and task states compared to NC.

Conclusions:

• MCI patients display altered distant synchronization of the background network during executive function tasks.
• The findings suggest impaired brain network reorganization underlies executive function deficits in MCI.
• This study offers novel insights into the neural basis of cognitive changes in MCI.