Hitouji Kayoko, Takahashi Masahiro, Iida Masahiro, Ohnuki Junichi, Furuya Hiroyuki
Department of Otorhinolaryngology, Tokai University School of Medicine, Iseharashi, Kanagawaken, Japan.
Aviat Space Environ Med. 2002 Sep;73(9):865-71.
In a previous study, we found that sensation, gaze, and posture during Coriolis stimulation differ considerably between vision and nonvision conditions during rotations at 60 degrees x s(-1). To determine the validity of these findings at higher velocities, we compared standing postures during Coriolis stimulation up to 150 degrees x s(-1) between vision and nonvision conditions.
The 19 subjects underwent 5-min rotation tests at 50 to 150 degrees x s(-1). While standing on a force platform attached to a rotating device, each subject tilted his or her head and then returned it to upright, first with the eyes covered, then with eyes open. Six subjects were re-examined 5 d later after 4 consecutive days of 20-min rotations with their eyes open. We assessed success and failure to stand and recorded the center of pressure during rotation.
Although success rates (number of successes/19) differed between vision and nonvision conditions at 50 degrees x s(-1) (94.7% vs. 57.9%), they steeply decreased as rotation velocity increased and showed no difference at 70 degrees x s(-1) and faster velocities. After the 4-d exposure, however, subjects could stand at higher velocities particularly under the vision condition. A patient with bilateral labyrinthine loss, being examined for reference, could stand at 110 degrees x s(-1) even with the eyes covered.
Untrained subjects frequently fell during high-speed Coriolis stimulation, apparently because vision was insufficient to provide a spatial reference frame from the stationary surroundings. Following rotation training with their eyes open, subjects appeared more able to use the visual reference frame and falls were reduced.
在之前的一项研究中，我们发现，在以60度×秒⁻¹的速度旋转时，科里奥利刺激期间的感觉、注视和姿势在视觉和非视觉条件下有很大差异。为了确定这些发现在更高速度下的有效性，我们比较了在视觉和非视觉条件下高达150度×秒⁻¹的科里奥利刺激期间的站立姿势。
19名受试者在50至150度×秒⁻¹的速度下进行了5分钟的旋转测试。在站在连接到旋转装置的测力平台上时，每个受试者先倾斜头部然后再将其恢复到直立状态，先是闭眼，然后是睁眼。6名受试者在连续4天每天睁眼进行20分钟旋转后5天再次接受检查。我们评估站立成功和失败情况，并记录旋转期间的压力中心。
尽管在50度×秒⁻¹时视觉和非视觉条件下的成功率（成功次数/19）有所不同（94.7%对57.9%），但随着旋转速度增加成功率急剧下降，在70度×秒⁻¹及更高速度下没有差异。然而，在4天的暴露之后，受试者能够在更高速度下站立，特别是在视觉条件下。作为参考进行检查的一名双侧迷路丧失患者，即使闭眼也能在110度×秒⁻¹的速度下站立。
未经训练的受试者在高速科里奥利刺激期间经常摔倒，显然是因为视觉不足以从静止环境中提供空间参考框架。在睁眼进行旋转训练后，受试者似乎更能够使用视觉参考框架，摔倒次数减少。
