Thresholds for the perception of hand-transmitted vibration: Dependence on contact area and contact location

Abstract

The detection of vibration applied to the glabrous skin of the hand varies with contact conditions. Three experiments have been conducted to relate variations in the perception of hand-transmitted vibration to previously reported properties of tactile channels. The effects of a surround around the area of contact, the size of the area of contact, the location of the area of contact, the contact force, and the hand posture on perception of thresholds were determined for 8 to 500 Hz vibration. Removal of a surround around a contact area on the fingertip elevated thresholds of the NP II channel (FA I fibers) at frequencies less than 31.5Hz and reduced thresholds of the Pacinian channel (FA II fibers) at frequencies greater than about 63 Hz. When no surround was present, thresholds reduced systematically as the contact area increased from the fingertip to the whole hand at frequencies from 16 to 125 Hz, although the decrease was not inversely proportional to the increase in contact area. The results are partly explained by spatial summation in the Pacinian channel (FA II fibers) and the involvement of the NP II channel (SA II) with some influence of biodynamic responses and contact pressures. There were regional differences in sensitivity over the hand within the NP I channel but not within the Pacinian channel: the NP I thresholds (less than 31.5 Hz) decreased from proximal to distal regions of the hand, whereas the Pacinian thresholds (125 Hz) were independent of contact location over the hand. 249 words (No more than 250 words)

Relation between vibrotactile perception thresholds and reductions in finger blood flow induced by vibration of the hand at frequencies in the range 8–250 Hz

“…Thresholds at the high frequencies (63, 125 and 250 Hz) were generally not correlated with thresholds at the low frequencies (8, 16 and 31.5 Hz), indicating that different channels mediated thresholds at low and high frequencies in most subjects. This is consistent with other studies of perception thresholds using the same apparatus and vibration applied to the fingertip (Morioka and Griffin, 2005;Morioka et al, 2008).…”

“…Perception thresholds at these frequencies were determined by the response of the Pacinian channel. Studies of masked thresholds show the difference in the sensitivity of the Pacinian channel and the next most sensitive channel (a non-Pacinian channel) is about 30 dB SL (Morioka and Griffin, 2005). The vibration magnitudes provoking significant reductions in finger blood flow (i.e., 10-15 dB SL) were only within the activation zone of Pacinian receptors.…”

“…The most sensitive channel depends on the frequency of the vibration, the contact conditions, the location on the hand, and some other factors. The Pacinian (P) channel, mediated by Pacinian corpuscles (also called FA II units), has the lowest threshold at frequencies greater than about 40 Hz when using a 6-mm vibrating contactor (Morioka and Griffin, 2005;Morioka, et al, 2008), and exhibits both spatial and temporal summation: reduced thresholds with increased area of excitation and increased duration of vibration (Verrillo 1962(Verrillo , 1963. Of the three non-Pacinian channels, the NPI channel often determines thresholds at frequencies between 4 and 40 Hz and is associated with Meissner corpuscles (FA I units), whereas the NPII and NPIII channels are associated with slow adapting fibres and have been identified from the results of psychophysical experiments (Capraro et al, 1979, Bolanowski et al, 1988, Verrillo et al, 2002.…”

Equivalent comfort contours for vertical vibration of steering wheels: Effect of vibration magnitude, grip force, and hand position

“…Much of the glabrous skin of their hands was in contact with the handle. The frequency-dependence of the threshold contours for the UPPER and the LOWER hand positions is similar to the frequency-dependence reported previously by Miwa (1967), Reynolds et al (1977) and Morioka and Griffin (2005b). .…”

Absolute thresholds for the perception of fore-and-aft, lateral, and vertical vibration at the hand, the seat, and the foot

“…Thresholds for the perception of vibration have been determined in studies of handtransmitted vibration [1][2][3][4][5] and in studies of whole-body vibration with seated subjects [6][7][8][9] and standing subjects [6][7]. However, there has been little investigation of perception thresholds for the foot resting on a vibrating surface.…”