The Influence of Head Position on Postural Vertical

描述(申请人提供)：这项研究的长期目标是进一步了解颈部体感和前庭信息在检测空间中的身体位置和产生姿势反应方面的相互作用。来自颈部传入、视觉、体感和前庭系统的信息被整合在一起，形成头部和躯干在空间中的三维表示，以产生适当的平衡反应。以前对前庭电流刺激和视觉流动刺激的研究表明，头对躯干的位置会影响由此产生的姿势摆动的方向。Horak和Peterka开发的前庭-躯体感觉相互作用的新模型表明，受试者站在其上的平台以正弦方式振荡增加了前庭信息的权重，从而形成姿势反应。我们将使用这个模型来研究对照组和单侧前庭病变患者颈传入神经与前庭系统之间的相互作用。在实验1中，我们将确定当头部旋转时，在正弦表面摆动中观察到的姿势垂直度的横向偏差是否会改变为更前移/后移的偏差。在实验2中，我们将确定在不同头部位置的行走过程中，是否会观察到垂直度的横向偏差。

DESCRIPTION (provided by applicant): The long-term goal of this research is to further understand the interaction between cervical somatosensory and vestibular information in the detection of body position in space and in generating postural responses. Information from the cervical afferents, visual, somatosensory and vestibular systems are integrated to form a three dimensional representation of the head and trunk in space for the generation of appropriate balance responses. Previous studies with galvanic vestibular stimulation and visual flow stimulation have shown that head-on-trunk position influences the direction of the resultant postural sway. A new model of vestibular-somatosensory interaction developed by Horak and Peterka have shown that sinusoidally oscillating a platform on which a subject stands increases the weighting of vestibular information for the formation of postural responses. We will use this model to investigate the interaction between cervical afferents and the vestibular system in control subjects, and subjects with unilateral vestibular lesions. In experiment 1 we will determine whether the lateral bias of postural verticality observed during sinusoidal surface oscillations with the head facing forward will change to a more anterior/ posterior bias when the head is rotated. In experiment 2 we will determine whether the lateral bias of verticality will be observed during ambulation with various head positions.