Individual differences in perceived pinch force and bite force

Six subjects made cross-modalmatches of pinch force and bite force to an electrocutaneous st4niulus. The electrocutaneous stimulus consisted ofbursts ofpulses, and the intensity ofthe stimulus was varied by changing the number of pulses per burst. All of the individual matching functions were fit well by powerfunctions. The scaling constants and exponents ofthe power functions covaried systematically with the maximum pinch force for 5 of the 6 subjects. The relationship was consistent with the hypothesis that subjects perceive their physical maxima equally, in agreement with Borg’s theory of relative perceived exertion. For both pinch force and bite force functions, the scale factors could be described by a single linear function ofthe exponents, suggesting that all of the matching functions converged at a single point with extreme values.