Pilot Studies in Adaptation in Parabolic Flight

抛物线飞行适应性试点研究

• 批准号: 6617147
• 负责人: MARK J SHELHAMER
• 金额: $ 14.8万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-01 至 2005-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6617147
• 关键词: aviation; clinical research; cues; environmental adaptation; eye movements; gravity; human subject; motion perception; otocyst /otolith; proprioception /kinesthesia; questionnaires; sensorimotor system; space perception; vestibuloocular reflex; video recording system

DESCRIPTION (provided by applicant): This study addresses adaptation to the unique environment of parabolic flight. Experiments will take place in a NASA aircraft that flies parabolic trajectories which make transitions between 0 g and 1.8 g approximately every 25 sec. This unusual motion environment, with changes in g level not normally experienced, presents a remarkable challenge to the body's adaptive processes. Indeed, many first-time flyers experience disorientation and motion sickness. Nevertheless, adaptive processes prevail and on the second and subsequent flights the experience is much more pleasant, indicating that significant adaptation has occurred in a very short time and after a very brief exposure (approximately one hour of parabolic maneuvers per flight). We propose to study the adaptive processes that take place in this situation. A battery of tests of vestibular and oculomotor function will be performed during the two different gravity levels in flight. The tests span a range of neural processes from low-level reflexive through higher-level cognitive, and are aimed in particular at otolith information (since these vestibular organs sense linear accelerations, including gravity) and vision (since visual information can in many cases substitute for vestibular information about self-orientation). The tests are: 1) ocular counterrolling (OCR), a reflexive torsional movement of the eyes in relation to head tilt in a gravity field as sensed by the otolith organs; 2) translational VOR (TVOR), a compensatory eye movement made in response to head translations that also depends on processing of otolith signals; 3) pitch angular VOR, which involves convergence of otolith and canal signals; 4) vertical ocular alignment, which is affected by gravity level; 5) subjective visual vertical, based on multi-sensory integration of orientation cues; 6) roll vection, which addresses the interaction of visual and otolith cues. Responses from new and from experienced flyers will be compared, and the progression of responses over consecutive flights will be assessed as adaptation develops. The tests address two competing hypotheses of how adaptation to parabolic flight is achieved: 1) there is adaptation to each separate gravity level (context-specific); 2) adaptation is more generalized to the overall flight experience (implying a non-g-specific change in sensory weighting). The information to be gained from this study of adaptation may lead to better understanding of the range of possible adaptive mechanisms, and might help us to determine those mechanisms which act most rapidly and effectively (as they do in parabolic flight) as candidates for use in rehabilitation of vestibular patients.

描述（由申请人提供）：本研究旨在适应抛物线飞行的独特环境。实验将在美国航天局的一架飞机上进行，该飞机飞行抛物线轨迹，大约每25秒在0 g和1.8 g之间转换。这种不寻常的运动环境，与g水平的变化通常不会经历，提出了一个显着的挑战，身体的适应过程。事实上，许多第一次飞行的经验迷失方向和晕动病。然而，适应过程占主导地位，在第二次和随后的飞行中，体验要愉快得多，这表明在非常短的时间内，在非常短暂的暴露（每次飞行大约一小时的抛物线机动）之后，已经发生了显著的适应。我们建议研究在这种情况下发生的适应过程。在飞行中的两个不同重力水平下，将进行一系列前庭和眼功能测试。这些测试涵盖了从低级反射到高级认知的一系列神经过程，并且特别针对耳石信息（因为这些前庭器官感知线性加速度，包括重力）和视觉（因为视觉信息在许多情况下可以替代关于自我定向的前庭信息）。测试包括：1）眼反旋（OCR），在耳石器官感觉到的重力场中眼睛相对于头部倾斜的反射性扭转运动; 2）平移VOR（TVOR），响应于头部平移而做出的补偿性眼运动，其也取决于耳石信号的处理; 3）俯仰角VOR，其涉及耳石和耳道信号的会聚; 4）垂直眼对准，其受重力水平影响; 5）主观视觉垂直，基于方向线索的多感觉整合; 6）滚动向量，其解决视觉和耳石线索的相互作用。将比较新飞行员和经验丰富的飞行员的反应，并随着适应的发展评估连续飞行中反应的进展。测试解决了两个相互竞争的假设，如何适应抛物线飞行实现：1）有适应每个单独的重力水平（特定的上下文）; 2）适应更普遍的整体飞行经验（意味着非g-特定的感觉权重的变化）。从这项适应性研究中获得的信息可能会导致更好地理解可能的适应性机制的范围，并可能帮助我们确定那些最迅速和有效的机制（如抛物线飞行）作为前庭患者康复的候选人。