The Effect of Auditory Cues on the Audiotactile Roughness Perception: Modulation Frequency and Sound Pressure Level

Scraping a surface with the finger tip is a multimodal event. We obtain information about the texture, i.e. roughness of the surface, at least through three different sensory channels, i.e. auditory, tactile and visual. People are highly skilled in using touch-produced sounds to identify texture properties. Sound pressure level, modulation frequency and pitch of the touch-induced scraping sounds are the important psychoacoustical determinants of the texture roughness perception. In this study, psychophysical experiments were conducted to investigate what are the relative contributions of the auditory and tactile sensory modalities to the multimodal (audiotactile) roughness percept?, what are the effects of the perceptual discrepancy between the modalities on the multimodal roughness judgment and how different modulation frequency and loudness conditions affect the subjects’ roughness perception.