Thresholds were determined from the arithmetic averages of the
logarithms of the root-mean-square vibration acceleration at the
reversals (i.e. a minimum of six reversals).
The experiment consisted of two sessions: one session for measuring
thresholds at the big toe, the medial ball, and the lateral ball
and another session for measuring thresholds at the fingertip, the
thenar eminence, and the heel. The two sessions, the two frequencies,
the three locations in each session, and the four contact areas
were presented in a balanced random order.
Room temperature was controlled by air conditioning within
the range 24–26 ◦C. Skin temperatures on the fingertip, big toe
and the heel were measured using a thermocouple, and were
in the range 25.8–30.9 ◦C, 26.3–30.7 ◦C and 31.9–36.3 ◦C, respectively