Miao T, Sakamoto K
Department of Communications and Systems, University of Electro-Communications, Tokyo, Japan.
Appl Human Sci. 1995 Jan;14(1):37-47. doi: 10.2114/ahs.14.37.
The effect of pseudo-fraction gravity on physiological tremor of the human finger (finger tremor) has been examined experimentally by immersing an index finger into water at different immersion levels. The pseudo-fraction gravity, gamma G, was established by water buoyancy at immersion level omega, G being gravitation acceleration and gamma between zero and unit. The nature of variations of finger tremor under the influence of gamma G is estimated based on FFT spectral analysis. It is illustrated that with a decrease in gamma, or equivalently an increase in omega, two dominant peaks remaining approximately constant in frequencies around 10Hz and 20Hz are found, while peak amplitude is decreased rapidly for higher peak and slowly for lower one. Theoretically the effect of pseudo-fraction gravity is analyzed in terms of a specific model for finger tremor. The experimental results presented in this paper are predicted rather well by two resonant modes which occurred in our model system. It is possible to conclude that the model, which is characterized by a pair of antagonistic muscles and two reflex pathways, provides an adequate quantitative description of finger tremor.
通过将食指浸入不同深度的水中，对伪分数重力对人手指生理震颤（手指震颤）的影响进行了实验研究。伪分数重力γG是由浸没深度ω处的水浮力确定的，G为重力加速度，γ在0到1之间。基于快速傅里叶变换（FFT）频谱分析估计了γG影响下手指震颤的变化特性。结果表明，随着γ的减小，或者等效地随着ω的增加，在频率约10Hz和20Hz处发现两个主导峰值频率大致保持不变，而较高峰值的峰值幅度迅速减小，较低峰值的峰值幅度缓慢减小。从手指震颤的特定模型角度对伪分数重力的影响进行了理论分析。本文给出的实验结果与我们模型系统中出现的两种共振模式预测相当吻合。可以得出结论，以一对拮抗肌和两条反射通路为特征的模型能够充分定量描述手指震颤。
