Cortical correlates in upright dynamic and static balance in the elderly

Area of Science:

• Neuroscience
• Gerontology
• Biomechanics

Background:

• Falls are a major cause of injury in older adults, with aging affecting balance control.
• Approximately 30% of adults aged 65+ fall annually, highlighting the need to understand balance mechanisms.
• Investigating neurophysiological control of balance in the elderly is crucial for fall risk reduction.

Purpose of the Study:

• To identify cortical and muscular activity differences during static and dynamic balance in young and old adults.
• To examine how dual-tasking (balance with a cognitive challenge) affects these neural and muscular correlates.
• To understand the distinct strategies employed by different age groups for postural control.

Main Methods:

• Recorded electroencephalography (EEG) and muscle activity in 9 elderly and 8 young healthy adults.
• Participants performed static and dynamic (core board) upright stance tasks.
• A visual oddball task was introduced to simulate dual-task conditions.

Main Results:

• Elderly showed increased anterior cortex delta rhythm during static balance; younger adults had more diffused fast rhythms.
• During dual-tasking, elderly exhibited increased theta activation in sensorimotor and occipital areas.
• Elderly utilized sensorimotor areas and increased muscle activity for dynamic balance, a strategy amplified during dual-tasking.

Conclusions:

• Older adults employ distinct neuro-muscular strategies for postural control compared to younger adults, particularly under dual-task conditions.
• These age-related differences in balance control strategies are significant, especially when cognitive and motor demands are combined.
• Findings can guide the development of targeted rehabilitative and assistive interventions for fall prevention in the elderly.