THE DEPENDENCE OF VIBROTACTILE THRESHOLD AND MAGNITUDE FUNCTIONS ON STIMULATION FREQUENCY AND SIGNAL LEVEL: A perceptual and neural comparison

F ranzén , O. The dependence of vibrotactile threshold and magnitude functions on stimulation frequency and signal level. A perceptual and neural comparison. Scand. J. Psychol ., 1969, 10 , 289–298.—Apparent intensity of vibrotactile signals was examined as a function of stimulation frequency and displacement. Two sorts of power transformations were observed. (1) The exponent decreased as frequency was increased. (2) At low signal levels perceived intensity was linearly related to the physical input. At a certain point on the intensity continuum an abrupt shift to a power function with a slope of 0.58 occurred. The successive change of the exponent of the magnitude functions is tentatively interpreted as a kind of successively increasing demultiplication in the rate of firing frequency in the sensory pathway. A dual mechanism of mechanoreception is discussed.