Burnett Theresa A, Larson Charles R
Department of Communication Disorders, Northwestern University, Evanston, Illinois 60208, USA.
J Acoust Soc Am. 2002 Sep;112(3 Pt 1):1058-63. doi: 10.1121/1.1487844.
When air conducted auditory feedback pitch is experimentally shifted upward or downward during steady phonation, voice pitch changes in response. The first pitch change is an automatic deflection opposite in direction to the feedback shift. It appears to help stabilize voice pitch by counteracting unintended changes. But what happens during an intended pitch change? If the purpose of the first pitch-shift response is to stabilize voice pitch around a fixed target, it should be suppressed during voluntary pitch changes. Alternatively, if the pitch-shift response is a general process of voice control it should be modified during intended pitch changes to bring production in line with the desired output. Auditory feedback pitch was shifted during steady pitch and upward glissando vocalizations by thirty trained singers. Contrary to the "steady-specific" hypothesis, pitch-shift responses occurred during dynamic pitch vocalizations. Responses were comparable in direction, peak time, and slope, but had significantly longer latency and smaller magnitude than responses elicited during steady note phonation. Results indicate that the early pitch-shift response is a general component of voice control that serves to automatically bring phonation pitch into agreement with an intended target, whether that target is constant or changing in time.
当在稳定发声过程中通过实验使气导听觉反馈音高向上或向下偏移时,嗓音音高会相应地发生变化。第一个音高变化是与反馈偏移方向相反的自动偏移。它似乎通过抵消意外变化来帮助稳定嗓音音高。但是在有意的音高变化过程中会发生什么呢?如果第一个音高偏移反应的目的是将嗓音音高稳定在一个固定目标周围,那么在自愿的音高变化过程中它应该被抑制。或者,如果音高偏移反应是嗓音控制的一个普遍过程,那么在有意的音高变化过程中它应该被调整,以使发声与期望的输出一致。三十名经过训练的歌手在稳定音高和向上滑音发声过程中气导听觉反馈音高发生了偏移。与“稳定特定”假设相反,在动态音高发声过程中出现了音高偏移反应。反应在方向、峰值时间和斜率上具有可比性,但与稳定音符发声过程中引发的反应相比,潜伏期明显更长,幅度更小。结果表明,早期音高偏移反应是嗓音控制的一个普遍组成部分,它有助于自动使发声音高与预期目标一致,无论该目标是恒定的还是随时间变化的。