Subjective perception of body sway

Area of Science:

• Biomechanics
• Neuroscience
• Gerontology

Background:

• Body sway is a key indicator of postural stability.
• Subjective perception of steadiness is crucial for balance assessment.
• Understanding the relationship between objective sway and subjective feeling is vital for clinical evaluation.

Purpose of the Study:

• To investigate the relationship between objective body sway measurements and subjective reports of steadiness.
• To compare this relationship across different age groups (young, elderly) and patient populations (neuropathic, parkinsonian).
• To examine the influence of stance and visual conditions on sway and perceived steadiness.

Main Methods:

• Utilized a stabilometric platform to record body sway in 20 young, 20 elderly, 20 neuropathic, and 20 parkinsonian subjects.
• Subjects stood in two stances (feet apart, feet together) and two visual conditions (eyes open, eyes closed).
• After each trial, subjects rated their steadiness on a 0-10 scale.

Main Results:

• A consistent inverse linear relationship was found between body sway (logarithmic scale) and subjective steadiness scores across all groups.
• Body sway and perceived steadiness varied with stance and visual conditions (eyes closed > eyes open, feet together > feet apart).
• Parkinsonian patients showed similar sway and scores to controls, while neuropathic patients had greater sway and altered visual-motor integration.

Conclusions:

• Subjective steadiness accurately reflects objective body sway, inversely proportional to its logarithm, irrespective of age or neurological condition.
• A common sensory integration mechanism for sway evaluation exists, with most groups utilizing visual input effectively.
• Basal ganglia integrity is not essential for sway evaluation, but neuropathic patients exhibit impaired visual-somatosensory integration.