Neurovascular coupling, cognitive reserve, and cognitive performance in mild cognitive impairment

Area of Science:

• Neuroscience
• Cognitive Science
• Medical Imaging

Background:

• Neurovascular coupling (NVC) impairment is linked to mild cognitive impairment (MCI).
• The precise relationship between NVC and cognitive function in MCI patients requires further elucidation.

Purpose of the Study:

• To investigate the associations between cognitive reserve (CR), NVC, and cognitive performance in MCI.
• To identify potential correlational patterns linking CR, NVC, and cognition in MCI.

Main Methods:

• Resting-state fMRI and arterial spin labeling were used to assess NVC measures (CBF/neural activity ratios like ALFF, fALFF, ReHo, DC) in 113 MCI patients and 83 healthy controls (HCs).
• Cognitive reserve was evaluated using the Cognitive Reserve Index Questionnaire.

Main Results:

• MCI patients exhibited heterogeneous NVC alterations compared to HCs, with increased CBF-ALFF coupling and trends toward decreased CBF-fALFF, ReHo, and DC coupling.
• Regionally, NVC ratios varied, increasing in visual/subcortical areas and decreasing in frontal/temporal lobes.
• Cognitive reserve, particularly education, was a strong cognitive predictor, and specific NVC ratios mediated the relationship between reserve and cognition.

Conclusions:

• Two patterns link CR to cognitive performance in MCI: a neural reserve pattern with weak NVC ties and a neural compensation pathway involving NVC.
• Multidimensional CR assessment and NVC measures show promise as indicators of neural compensation in MCI.