Takahashi M, Ogata M, Miura M
Department of Otolaryngology, Yamaguchi University School of Medicine, Japan.
J Vestib Res. 1997 Mar-Jun;7(2-3):179-87.
In order to clarify the significance of motion sickness in the vestibular system, we compared the findings of experimental motion sickness between different kinds of subjects, some of which were already reported. Subjects were healthy adults, healthy children between the ages of 4 and 15 years, and patients with congenital and acquired labyrinthine loss. They were asked to walk while wearing horizontally and vertically reversing goggles. Equilibrium ataxia as well as motion sickness were evoked by horizontal reversal, but not by vertical reversal in healthy subjects. Kindergarten children exhibited severe ataxia, but little nausea. The frequency of severe ataxia decreased during growth, inversely as the frequency of nausea syndrome increased. Although a patient with acquired loss became severely ataxic, a patient with congenital loss did not show any ataxia at all. The present study suggests that vestibular cues are indispensable to the ego-spatial relationship in the brain, and once the ego-spatial relationship becomes inadequate, discomfort acts as a safety device to brake uncontrollable actions. Then, perception of the outer world may automatically adjust voluntary actions by affecting motor commands. The importance of visual cues for representing an alternative framework may differ between congenital and acquired labyrinthine loss.
为了阐明晕动病在前庭系统中的意义，我们比较了不同类型受试者的实验性晕动病结果，其中一些结果已有报道。受试者包括健康成年人、4至15岁的健康儿童以及先天性和后天性迷路丧失患者。他们被要求戴着水平和垂直反转的护目镜行走。水平反转会引发平衡失调以及晕动病，但健康受试者的垂直反转不会引发这些症状。幼儿园儿童表现出严重的共济失调，但几乎没有恶心感。随着年龄增长，严重共济失调的发生率降低，而恶心综合征的发生率则相反增加。虽然后天性迷路丧失的患者会出现严重共济失调，但先天性迷路丧失的患者根本没有表现出任何共济失调。本研究表明，前庭线索对于大脑中的自我空间关系不可或缺，一旦自我空间关系变得不充分，不适感就会作为一种安全装置来抑制无法控制的动作。然后，对外界的感知可能会通过影响运动指令来自动调整自主动作。对于代表替代框架而言，视觉线索的重要性在先天性和后天性迷路丧失之间可能有所不同。
