Neurovascular de-coupling underlies dual-task cost across cognitive abilities.

Area of Science:

• Neuroscience
• Gerontology
• Cerebrovascular Physiology

Background:

• Cognitive decline in aging is a significant public health concern.
• Understanding the relationship between cerebral blood flow and cognitive function is crucial for early detection and intervention.
• Middle cerebral artery (MCA) velocity reflects cerebral blood flow and may be linked to cognitive performance.

Purpose of the Study:

• To investigate the association between MCA velocity during motor and cognitive tasks and cognitive performance in older adults.
• To determine if MCA velocity can serve as a biomarker for subclinical cognitive function.

Main Methods:

• Fifty-six older adults (mean age 75 years) performed seated working memory, overground walking, and dual tasks.
• Continuous MCA velocity was measured using mobile devices.
• Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA).

Main Results:

• Higher MCA velocity correlated with faster gait speed, better working memory, and higher MoCA scores.
• Individuals with lower MoCA scores exhibited lower MCA velocity and poorer performance on cognitive and gait tasks.
• The increase in MCA velocity during dual-tasking (hyperemic response) was significantly associated with MoCA scores.

Conclusions:

• Cerebral blood flow dynamics, measured by MCA velocity during functional tasks, are associated with cognitive function in older adults.
• MCA velocity may act as a non-invasive biomarker for subclinical cognitive impairment.
• This study introduces a novel method for assessing neurovascular coupling during everyday activities like walking.