Altered postural control in persons with cognitive impairment during visual feedback tasks

Area of Science:

• Gerontology
• Neuroscience
• Biomechanics

Background:

• Postural stability is crucial for elderly individuals.
• Cognitive impairment can affect motor control and sensory integration.
• Visual feedback can alter postural strategies.

Purpose of the Study:

• To compare postural stability and strategies between elderly subjects with cognitive impairment and controls under eyes open and visual feedback conditions.
• To investigate the impact of visual feedback on postural control in these groups.
• To identify objective markers for posture control disorders in cognitive impairment.

Main Methods:

• Evaluated postural stability using center-of-pressure (COP) mean radius and velocity.
• Assessed postural strategies via COP-center-of-mass (COM) signal frequency and damping.
• Measured performance in visual feedback trials by the ratio of time COP remained within a target.
• Compared 15 elderly subjects with cognitive impairment (SwCI) and 17 controls.

Main Results:

• Both groups showed similar postural stability with eyes open.
• Controls spent significantly more time within the visual target than SwCI.
• Visual feedback increased velocity and frequency in controls, but not in SwCI.
• Visual feedback significantly increased damping more in SwCI than in controls.
• SwCI exhibited impaired sway control and sensory integration deficits.

Conclusions:

• Elderly individuals with cognitive impairment struggle to utilize visual feedback for postural control.
• Center-of-pressure velocity, COP-COM frequency, and damping can objectively identify posture control disorders.
• Increased damping in controls during visual feedback may indicate early cognitive impairment undetectable by standard tests.