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Impedance changes elicited by electrocutaneous stimulation.

G Djupesland·G Flottorp·A Sundby
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Abstract

Electrical stimulation of the skin in the cavum conchae is followed by bilateral changes in the acoustic impedance of the ear due to reflex contraction of the stapedius muscle. A stimulator and a special surface electrode for electrical stimulation of the skin have been developed. The apparatus produces square-wave constant-current pulses independent of the electrical impedance of the electrode and the skin, and its hazard-proof. The effect of five independently variable stimulus parameters upon the elicited impedance changes has been examined in order to find a stimulus producing a large and reproducible impedance change without causing discomfort to the subject. Although a pronounced habituation phenomenon tends to mask the cause to effect relation of the various parameters, the results indicate that an appropriate stimulus is a pulse train of 0.5 s duration, consisting of individual pulses of a frequency of 200 Hz and 1 ms duration. The stimulus is applied at 10-second intervals.

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Acoustic StimulationAdultAudiometryEar, ExternalEar, MiddleElectric StimulationElectrodesHumansMiddle AgedMuscle ContractionReflexSkin Physiological PhenomenaJournal Article

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G Djupesland, G Flottorp, A Sundby. Impedance changes elicited by electrocutaneous stimulation.. https://doi.org/10.3109/00206097709071846

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