Title: The Role of Visual and Vestibular Systems in Equilibrium
Abstract: Equilibrium is maintained by the visual, vestibular and spinal systems. After unilateral labyrinthectomy, animals showed specific posture changes. Rabbits showed 90° head tilting, whereas cats showed 15°–45° head tilting. Rhesus monkeys showed 5°–15° head tilting. Oculomotor responses, that is optokinetic nystagmus were increasingly stronger in rabbits, cats and monkeys. Vestibular responses were examined by the vestibulo-oculomotor reflex. Oculomotor responses were different in various animals, however vestibular responses provoked by caloric stimuli or rotation did not show large differences in each animal. The visual system works to weaken the vestibular imbalance. Visual suppression showed a large difference across animals. Visual suppression increased from 0 % to 50 % in rabbits, cats and monkeys, respectively. Thus, the vestibular contribution in equilibrium is very strong in rabbits and no visual contribution is seen. Therefore rabbits show marked posture change after unilateral labyrinthectomy. The percent of visual contribution in equilibrium increases in rabbits, cats and rhesus monkeys, respectively. Degree of the posture changes after unilateral labyrinthine function loss in mammals depend on the contribution of visual and vestibular systems in equilibrium. Equilibrium is maintained by the visual, vestibular and spinal systems. After unilateral labyrinthectomy, animals showed specific posture changes. Rabbits showed 90° head tilting, whereas cats showed 15°–45° head tilting. Rhesus monkeys showed 5°–15° head tilting. Oculomotor responses, that is optokinetic nystagmus were increasingly stronger in rabbits, cats and monkeys. Vestibular responses were examined by the vestibulo-oculomotor reflex. Oculomotor responses were different in various animals, however vestibular responses provoked by caloric stimuli or rotation did not show large differences in each animal. The visual system works to weaken the vestibular imbalance. Visual suppression showed a large difference across animals. Visual suppression increased from 0 % to 50 % in rabbits, cats and monkeys, respectively. Thus, the vestibular contribution in equilibrium is very strong in rabbits and no visual contribution is seen. Therefore rabbits show marked posture change after unilateral labyrinthectomy. The percent of visual contribution in equilibrium increases in rabbits, cats and rhesus monkeys, respectively. Degree of the posture changes after unilateral labyrinthine function loss in mammals depend on the contribution of visual and vestibular systems in equilibrium.
Publication Year: 1977
Publication Date: 1977-01-01
Language: en
Type: article
Indexed In: ['crossref']
Access and Citation
Cited By Count: 2
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot