Department of Otolaryngology-Head and Neck Surgery, Washington University School of Medicine, St Louis, Missouri 63110, USA.
Laryngoscope. 2012 Jun;122(6):1379-84. doi: 10.1002/lary.23329. Epub 2012 Apr 3.
OBJECTIVES/HYPOTHESIS: Integration of balance-related cues from the vestibular and other sensory systems requires that they be perceived simultaneously despite arriving asynchronously at the central nervous system. Failure to perform temporal integration of multiple sensory signals represents a novel mechanism to explain symptoms in patients with imbalance. This study tested the ability of normal observers to compensate for sensory asynchronies between vestibular and auditory inputs.
Double-blinded experimental design.
We performed whole-body rotations about the earth-vertical axis following a raised-cosine trajectory at 0.5 and 1.0 Hz to several peak velocities up to a maximum of 180°/s in five normal subjects. Headphones were used to present a diotic auditory stimulus at various times relative to the onset of the rotation. Subjects were required to indicate which cue occurred first.
The vestibular stimulus needed to be presented 61 milliseconds (at a stimulus frequency of 0.5 Hz) and 19 milliseconds (at 1.0 Hz) before the auditory stimulus. Stimuli presented within a window of 300 milliseconds (at 0.5 Hz) to 200 milliseconds (at 1.0 Hz) were judged to be simultaneous.
The central nervous system must accommodate for delays in perception of vestibular and other sensory cues. Inaccurate temporal integration of these inputs represents a novel explanation for symptoms of imbalance.
目的/假设：尽管前庭和其他感觉系统的平衡相关线索异步到达中枢神经系统，但它们需要被同时感知才能实现整合。无法对多个感觉信号进行时间整合，代表了一种解释平衡障碍患者症状的新机制。本研究测试了正常观察者补偿前庭和听觉输入之间感觉时滞的能力。
双盲实验设计。
我们让 5 名正常受试者沿地球-垂直轴进行余弦上升轨迹的全身旋转，在 0.5 和 1.0 Hz 的几个峰值速度下达到最大 180°/s。耳机用于在旋转开始时以不同的时间呈现双声道听觉刺激。要求受试者指出哪个线索先出现。
在 0.5 Hz 的刺激频率下，听觉刺激需要在前庭刺激之前提前 61 毫秒出现；在 1.0 Hz 时则需要提前 19 毫秒。在 0.5 Hz 时的 300 毫秒窗口内到 1.0 Hz 时的 200 毫秒窗口内呈现的刺激被判断为同时出现。
中枢神经系统必须适应前庭和其他感觉线索感知的延迟。这些输入的时间整合不准确，代表了对平衡障碍症状的新解释。
