Suppressing Discomfort Caused by Electrical Stimulation Using a Local Anesthetic Cream

Abstract

Electrical stimulation is one of the methods that have been developed to stimulate skin sensations, and can provide sensations such as vibration and pressure by varying the polarity of the stimulus. Such stimuli can be combined to generate a variety of tactile sensations. However, itching or painful sensations are elicited with increasing amounts of electrical current. To address this major problem, in this study, we developed a method to suppress the itching and pain caused by electrical stimulation while presenting stable pressure and vibration sensations. We applied an anesthetic cream containing the commonly used local anesthetics lidocaine and propitocaine to reduce pain and itching associated with electrical stimulation. In particular, we examined the effects of the local anesthetic cream on pain and tactile thresholds. The results showed a significant relationship between the application of the cream and the dynamic range (i.e., pain and tactile thresholds) of the stimulating current. Thus, our proposed approach considerably improved the quality of the participants' subjective experience with electrical stimulation technology.