Department of Otolaryngology, University of Rochester, 601 Elmwood Avenue, Box 629, Rochester, NY 14642, USA.
Exp Brain Res. 2012 Jun;219(4):477-87. doi: 10.1007/s00221-012-3105-9. Epub 2012 May 5.
A general theme in sensory perception is that exposure to a stimulus makes it seem more neutral such that perception of subsequent stimuli is shifted in the opposite direction. The visual motion aftereffect (MAE) is an extensively studied example of this. Although similar effects have been described in other sensory systems, it has not previously been described in the vestibular system. Velocity storage has been extensively studied in the vestibular system and suggests a persistence of perception in the direction of the initial movement. The current study sought to determine how motion perception is influenced by prior movement in darkness. Thirteen human subjects (mean age 41, range 21-68) underwent whole-body fore-aft translation. The threshold of vestibular motion discrimination perception was measured using a single interval (1I) of motion lasting 0.5 s in which subjects identified their direction of motion as forward or backward using an adaptive staircase. The translation aftereffect (TAE) was measured in 2-interval (2I) experiments: The adapting stimulus moved 15 cm in 1.5 s (peak velocity 20 cm/s, peak acceleration 42 cm/s(2)). After a fixed inter-stimulus interval (ISI) of 0.5, 1.0, 1.5, or 3 s, a second stimulus lasting 0.5 s was delivered and the subject identified the perceived direction of the second test stimulus. The test stimulus was determined using an adaptive staircase. The ISI was constant within the block, but adapting stimuli directions were randomly interleaved. During the 1I condition, the response bias was near zero in all subjects. With a 2I stimulus, 8 of 13 subjects demonstrated a significant bias. At an ISI of 0.5 s, a minority of subjects demonstrated a bias in the same direction as the adapter. When the ISI was 1, 1.5, or 3 s, all subjects who demonstrated a significant TAE had one in the opposite direction of the adapter, similar to that seen for MAE. When averaged across subjects, the TAE was significant with ISIs of 1.0 s and above. These findings demonstrate that perception of vestibular stimuli depends on prior motion. This has important implications for understanding and quantifying vestibular perception.
感觉知觉的一个普遍主题是，暴露于刺激会使其显得更加中性，从而导致对后续刺激的感知向相反方向转移。视觉运动后效（MAE）就是一个广泛研究的例子。尽管在其他感觉系统中也描述了类似的效应，但以前尚未在前庭系统中描述过。前庭系统中广泛研究了速度存储，这表明在初始运动方向上存在感知的持久性。本研究旨在确定先前在黑暗中运动如何影响运动知觉。13 名人类受试者（平均年龄 41 岁，范围 21-68 岁）接受了全身前后平移。使用持续 0.5 秒的单个运动间隔（1I）测量前庭运动辨别感知的阈值，在此期间，受试者使用自适应阶梯法识别他们的运动方向是向前还是向后。在 2 间隔（2I）实验中测量了平移后效（TAE）：适应刺激在 1.5 秒内移动 15 厘米（峰值速度 20 厘米/秒，峰值加速度 42 厘米/秒 2 ）。在固定的刺激间间隔（ISI）0.5、1.0、1.5 或 3 秒后，会输送第二个持续 0.5 秒的测试刺激，受试者识别第二个测试刺激的感知方向。测试刺激使用自适应阶梯法确定。ISI 在块内保持不变，但适应刺激的方向随机交错。在 1I 条件下，所有受试者的反应偏差接近零。对于 2I 刺激，13 名受试者中有 8 名表现出明显的偏差。在 ISI 为 0.5 秒时，少数受试者表现出与适配器相同方向的偏差。当 ISI 为 1、1.5 或 3 秒时，所有表现出明显 TAE 的受试者都有一个与适配器相反的方向，这与 MAE 相似。当平均在受试者之间时，当 ISI 为 1.0 秒及以上时，TAE 具有统计学意义。这些发现表明，前庭刺激的感知取决于先前的运动。这对于理解和量化前庭感知具有重要意义。
