Repeated visually-guided saccades improves postural control in patients with vestibular disorders

Area of Science:

• Neuroscience
• Ophthalmology
• Vestibular System Research

Background:

• Persistent asymmetry in dynamic vestibulo-ocular gain can be compensated by sensory substitution.
• Saccadic eye movements are crucial for maintaining foveal fixation during head movements.

Purpose of the Study:

• To investigate if saccadic eye movements can compensate for impaired vestibulo-spinal reflexes.
• To determine if saccadic eye movements enhance postural control in patients with vestibular disorders and balance dysfunction.

Main Methods:

• Static posturography was used to evaluate 27 patients with unilateral labyrinthine hypofunction, 24 with central vestibular disorders, and 24 controls under three visual conditions.
• A second experiment involved 46 patients with central or peripheral vestibular disorders undergoing 12 training sessions of visually-guided saccades.

Main Results:

• A higher percentage of labyrinthine-defective patients showed decreased body sway during saccadic tasks compared to central vestibular disorder patients and controls.
• Both saccadic performance and postural control improved in all patients after training, with greater effects seen in peripheral vestibular disorder patients.
• A specific questionnaire indicated a general reduction in perceived impairment from balance disorders post-rehabilitation.

Conclusions:

• Visually-guided saccades show potential as a rehabilitation technique for improving postural control in patients with vestibular disorders.
• The effectiveness of saccadic eye movement training is more pronounced in patients with peripheral vestibular disorders.
• Sensory substitution via saccadic eye movements offers a promising approach for managing balance dysfunction.