THE INFLUENCE OF INTENSITY AND DURATION OF ELECTRICAL STIMULATION ON SUBJECTIVE VARIABLES

Abstract : The unpleasantness and subjective duration of an A.C. current of 50 c/sec applied to two fingers was scaled by subjects using the method of magnitude estimation. Stimulation was varied with regard to both intensity, ranging between 1.5 and 3.5 times the individual sensation threshold, and duration, ranging from 0.18 to 1.72 sec. It was found (1) that unpleasantness increased approximately logarithmically with stimulus duration, (2) that unpleasantness was a power function, with the exponent 1.5, of stimulus intensity measured with the sensation threshold as zero point, (3) that subjective duration was essentially linearly related to stimulus duration, and (4) that subjective duration increased approximately logarithmically with intensity of stimulation. (Author)