Multi-Task Assessment of Context-Specific Gait Changes to Virtual Reality-Based Visual Perturbations.

Area of Science:

• Biomechanics
• Neuroscience
• Human Movement Science

Background:

• Conventional gait assessments may miss early balance issues.
• Sensory conflict, like visual perturbations, can reveal subtle gait abnormalities.
• Instrumented gait analysis offers objective measurement of gait parameters.

Purpose of the Study:

• To investigate if instrumented gait analysis with VR-visual perturbations can detect task-dependent gait adaptations.
• To assess if discordant sensory information reveals subclinical balance deficits.
• To evaluate the sensitivity of a multi-task, perturbation-based framework for gait instability.

Main Methods:

• Ten healthy adults performed 10 walking tasks under four visual conditions (no VR, unperturbed VR, optic flow VR, flickering light VR).
• Tasks included steady-state and balance-challenging conditions like tandem gait and obstacle negotiation.
• Spatiotemporal gait parameters were measured using an instrumented walkway.

Main Results:

• Visual perturbations induced task-dependent gait adaptations, not uniform changes.
• Optic flow increased stride width during pivot turns and horizontal head turns.
• Tandem gait under optic flow showed increased temporal and spatial gait variability, indicating reduced consistency.

Conclusions:

• VR-delivered visual perturbations identified specific alterations in gait stability and consistency.
• These changes were not apparent during unperturbed walking.
• A multi-task, perturbation-based approach may improve detection of subtle gait instability.