Goodwin A W, John K T, Darian-Smith I
Department of Anatomy, University of Melbourne, Parkville, Victoria, Australia.
Exp Brain Res. 1989;77(1):79-86. doi: 10.1007/BF00250569.
Skin on the fingertips of humans and monkeys was stimulated by a probe vibrating with a sinusoidal displacement. The probe and the skin were illuminated stroboscopically and were viewed through a dissecting microscope. The stroboscope was triggered by the sinusoidal generator via a digital delay, so that the position of both the probe and the skin could be measured at regular intervals during the cycle. Six frequencies and 3 amplitudes of vibration were used. During a portion of the cycle the probe and the skin separated, so that the skin waveform was a clipped sinusoid. An increase in stimulus frequency increased the fraction of the cycle during which the probe and the skin were separated. Adding a static pre-indentation to the vibration reduced this fraction, and for this condition a decrease in vibratory amplitude also decreased the fraction. Thus the skin motion contained harmonics that were not present in the probe motion, and the harmonic content differed for different stimulus conditions.
用一个以正弦位移振动的探头刺激人类和猴子指尖的皮肤。探头和皮肤用频闪仪照亮，并通过解剖显微镜观察。频闪仪由正弦发生器通过数字延迟触发，这样在周期内可以定期测量探头和皮肤的位置。使用了六个频率和三种振动幅度。在周期的一部分时间里，探头和皮肤分离，因此皮肤波形是一个截断的正弦波。刺激频率的增加会增加探头和皮肤分离的周期部分。在振动中增加静态预压痕会减少这一部分，在这种情况下，振动幅度的减小也会减少这一部分。因此，皮肤运动包含了探头运动中不存在的谐波，并且不同刺激条件下的谐波含量不同。
