Department of Periodontology (Laboratory of Oral Physiology), Faculty of Medicine, Catholic University of Leuven, Capucijnenvoer 7, B-3000 Leuven, Belgium.
J Electromyogr Kinesiol. 1993;3(2):103-11. doi: 10.1016/1050-6411(93)90005-H.
The contribution of visual feedback to visuomotor tracking of jaw, head and finger was established by delaying the visual feedback display. Fourteen subjects (seven females, seven males; 20-30 years of age) used a movable metal bar to track a pseudorandom waveform on an oscilloscope screen. The tracking signals were recorded by means of a linear variable displacement transducer, amplified and digitized. Two approaches were applied for data analysis: (1) a cross-correlation analysis; (2) a power spectral analysis. On delaying the visual display, response delays for finger tracking increased significantly. A significant spectral shift occurred when a delayed feedback display (0.5-1.0 s) was introduced in both head and finger tracking experiments. A spectral change also occurred after inducing finger fatigue. On the other hand, neither the response delays nor the median frequencies of jaw tracking signals were significantly affected by modifications in the visual feedback display or by maximal voluntary clenching. Another interesting finding was the increase of the median frequency after periodontal anaesthesia. It was concluded that visual information is predominantly involved in finger and head tracking. Interactions between the visual system and the jaw motor system seem unlikely. Jaw tracking control probably relies on well-developed proprioceptive and exteroceptive inputs.
视觉反馈对下颌、头部和手指的运动跟踪的贡献通过延迟视觉反馈显示来确定。14 名受试者（7 名女性，7 名男性；20-30 岁）使用可移动金属棒在示波器屏幕上跟踪伪随机波形。跟踪信号通过线性可变位移传感器记录、放大和数字化。数据分析采用了两种方法：（1）互相关分析；（2）功率谱分析。当延迟视觉显示时，手指跟踪的响应延迟显著增加。在头部和手指跟踪实验中引入延迟反馈显示（0.5-1.0 s）时，会发生显著的频谱移位。手指疲劳后也会发生频谱变化。另一方面，无论是改变视觉反馈显示还是最大自主紧握，都不会对手部跟踪信号的响应延迟或中值频率产生显著影响。另一个有趣的发现是牙周麻醉后中值频率的增加。结论是视觉信息主要参与手指和头部的跟踪。视觉系统与颌运动系统之间的相互作用似乎不太可能。下颌跟踪控制可能依赖于发达的本体感觉和外感受输入。
