Brain activity during dual-task standing in older adults

Area of Science:

• Neuroscience
• Gerontology
• Biomechanics

Background:

• Performing cognitive tasks while standing in older adults can predict future falls and cognitive decline.
• The neurophysiological mechanisms of dual-tasking and its impact on postural control in older adults are not well understood.

Purpose of the Study:

• To investigate the effects of dual-task standing on brain activity in older adults using electroencephalography (EEG).
• To test the hypothesis that dual-task standing decreases alpha power and increases the theta/beta power ratio compared to quiet standing.

Main Methods:

• Thirty healthy older adults participated in four separate visits.
• EEG and postural sway were recorded during quiet standing and dual-task standing (serial subtraction).
• EEG metrics (alpha, theta, beta power, theta/beta ratio) were analyzed in specific brain regions.

Main Results:

• Dual-tasking significantly decreased alpha power in central brain regions and increased the theta/beta power ratio in anterior regions.
• Increased theta/beta ratio during dual-tasking correlated with greater postural sway (dual-task cost).
• Higher alpha power in right anterior and central regions during dual-tasking was associated with increased postural sway velocity.

Conclusions:

• Dual-task standing alters brain oscillatory activity (alpha and theta/beta power) in older adults.
• Changes in the theta/beta power ratio may reflect the ability to manage postural control during cognitive tasks.
• Modulating brain activity could be a future strategy to reduce dual-task costs and improve stability in older adults.