Background: Vibrotactile stimuli are widely used to study the functional characteristics of the haptic sense. Although many vibrotactile stimulators are commercially available, most are expensive. Objective: We developed a low-cost vibrotactile stimulation system using a Nintendo Wii Remote and a personal computer. In the present study, we examined the validity and accuracy of this vibrotactile stimulation system. Method: In the first experiment, we measured the linearity of vibration amplitude and changes in peak vibration frequency generated by the Wii Remote as a function of activation intensity. In the second experiment, the effect of vibrotactile stimuli applied to the dorsal surface of hand on two-point discrimination threshold at the index finger was examined in twelve participants. Results: The peak vibration frequency was about 150 Hz irrespective of vibration intensity, which would effectively activate fast adapting type II (FAII) cutaneous mechanical receptors. The two-point discrimination threshold measured at the third pad of the index finger decreased significantly when a near-threshold vibrotactile stimulus was applied to the dorsal hand, a response termed stochastic resonance (SR). These SR results are consistent with findings in the other sensory systems, such as auditory, visual, and somatosensory systems. Conclusion: This newly developed stimulation system produces controllable vibrotactile stimuli useful for study of the haptic sense.
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