Szeto A Y, Farrenkopf G R
Department of Electrical and Computer Engineering, San Diego State University, CA 92182-0190.
Ann Biomed Eng. 1992;20(6):647-65. doi: 10.1007/BF02368611.
The effects of a frequency modulated electrocutaneous signal's (code's) characteristics on the interpretability of the signal were investigated using an electrocutaneous tracking approach. The characteristics investigated include the functional relationship (exponential and hybrid) between an informational signal and the stimulation frequency, the range of stimulation (2-50 Hz and 2-100 Hz), and the impact of pulse width compensation on a code's efficacy. The interpretability of six different single bipolar electrode codes was examined by 30 subjects using a balanced incomplete block experimental design. Codes with exponentially shaped transfer functions resulted in generally lower electrocutaneous tracking errors than codes utilizing hybrid-shaped transfer functions. Hybrid codes had a transfer function that was linear in the lower frequency range and exponential in the higher frequency range. Codes with a 2-100 Hz frequency range were interpreted better than codes with a 2-50 Hz frequency range. The use of pulse width compensation to maintain a more even level of stimulation intensity had a slightly negative effect on the subjects' abilities to cutaneously track the information signal.
采用皮肤电跟踪方法，研究了调频皮肤电信号（编码）特征对信号可解释性的影响。所研究的特征包括信息信号与刺激频率之间的函数关系（指数型和混合型）、刺激范围（2 - 50Hz和2 - 100Hz）以及脉冲宽度补偿对编码效果的影响。30名受试者采用平衡不完全区组实验设计，对六种不同的单极电极编码的可解释性进行了检验。具有指数型传递函数的编码通常比采用混合型传递函数的编码产生更低的皮肤电跟踪误差。混合型编码的传递函数在低频范围内是线性的，在高频范围内是指数型的。频率范围为2 - 100Hz的编码比频率范围为2 - 50Hz的编码更容易被解释。使用脉冲宽度补偿来维持更均匀的刺激强度水平，对受试者通过皮肤跟踪信息信号的能力有轻微的负面影响。
