Effects of some different pulse parameters on the perception of intravaginal and intra-anal electrical stimulation

Abstract

Electrical stimulation was performed in male and female subjects by means of intra-anal and intravaginal electrode carriers. Rectangular constant voltage pulses of alternating polarity, pulse repetition rate 10 Hz, and pulse durations between 0·1 and 5 ms were tested. The perception of stimulation was used as a measure of stimulation efficiency and the voltage amplitudes at detection threshold and at maximum tolerance were recorded. The aim of the study was to determine the voltage requirements of a new, totally integrated stimulation device for intravaginal application. The voltage requirement of the 0·1 ms pulse was more than twice that of the 5·0 ms pulse for an equal effect, its power dissipation was considerably lower. The detection threshold was significantly higher with intravaginal than with intra-anal stimulation. There was also a larger variation in voltage amplitudes between female subjects, whereas the ratio between maximum tolerance and detection threshold amplitudes was quite small. In intra-anal stimulation the scatter in threshold voltage between male subjects was smaller, but an almost twofold increase of the threshold voltage amplitude was required to reach the maximum tolerance level. The study points to the necessity of having adjustable stimulation parameters in intravaginal stimulation devices. Stimulation efficacy may be changed equally well by varying pulse duration as pulse amplitude.