On the Vibrational Sensitivity in Different Regions of the Body Surface

Abstract

Summary. Vibratory thresholds in different parts of the body were determined with an electro‐dynamic apparatus. The lowest threshold amplitudes were found within the frequency range 200—450 Hz. In the finger‐tips these may be as small as 0.02 μp. Hands and the soles of the feet are most sensitive, whereas the vibratory thres‐hold values are highest in the abdominal and the gluteal regions.

Sensing Performance of a Vibrotactile Glove for Deaf-Blind People

“…the 170 Hz burst stimulus contributes to the performance because of the high vibrotactile sensitivity of the fingers at that frequency [42]. Thus, the results should be consistent with these statements.…”

“…The ratio between the applied amplitude and the achieved stimulus should be taken into account, as it is related to the tactor rotation frequency. The obtained 170 Hz is close to the range of frequencies with the lowest perception threshold amplitudes and, at that frequency, there is a sensitivity peak at the fingers that reinforces the effect [42]. This makes the HMI vibrotactile stimuli remain in conscious awareness.…”

Temperature can sharpen tactile acuity

“…The rank order of weight sensitivity of the body regions tested turned out to correlate almost perfectly with the rank order for the two-point limen and point localization, as measured by Weinstein (1968). There was, however, no correlation with two other measures of dermal sensitivity, namely, punctate pressure (Weinstein, 1968) and vibration (200 Hz) threshold (Wilska, 1954). Although he gave no quantitative data, Weber reported as early as 1834, in De Tactu, a correlation between weight sensitivity and acuity: "Weights arouse a stronger pressure sensation in those parts of the skin where our tactile acuity for the separation of the compass legs is best" (Weber, 1978, p. 121).…”

Vibrotactile localization on the arm: Effects of place, space, and age

“…Consequently, tactile vibratory sensitivity will be influenced by where, as well as how, one stimulates the skin. This can be seen in Wilska's (1954) study with 200-Hz stimuli, a rare demonstration of this variation in sensitivity over the body's surface. In addition, however, exploration of the characteristics of the structures responsible for tactile sensitivity (at least on glabrous skin) reveals that each of these channels has its own particular spatial response characteristics as well.…”

“…Boring also discusses Vierordt's (1870) "law of mobility," which argued that thresholds change continuously along limbs, with a change in the slope of the function as joints, such as the wrist or elbow, are crossed. Although vibrotactile thresholds have occasionally been recorded at individual sites on the arm or wrist (e.g., Verrillo, 1966;Wilska, 1954), a systematic, quantitative series of measurements has not been done over its whole length. Because stimuli, such as those to be studied here, could be localized on the basis of gross differences in perceived magnitude, resulting from varying sensitivity over the seven loci, it was deemed necessary to measure thresholds at the sites to be tested in the later experiments.…”