Variability in human response to whole-body vibration. The effects of instructions.

Abstract

Two studies are described in this paper with the aim of assessing the degree to which the instructions given to a subject during an experiment designed to investigate human reaction to vibration, affect the vibration equal sensation contour which is produced. In the first study, 100 subjects produced equal sensation contours by equating pairs of vibration stimuli. After each pair, subjects were required to record the basis on which they had made their judgements. The results demonstrated that subjects differ in the concepts which they use to equate vibration stimuli, although the majority equate in terms of the degree to which parts of the body are shaken. In the second study, 48 subjects were required to produce equal sensation contours using the terms of either ‘comfort’ or ‘discomfort’ or ‘body shake’ or ‘sensation’. The overall contour shapes produced by the four instruction groups were not significantly different, although the frequency ranges of maximum vibration sensitivity were shown to be signifi...