Decruitment of the Perception of Changing Sound Intensity for Simulated Self-motion

Of the many cues that could be used to gauge selfmotion, auditory cues seem to be the least studied. Listeners could potentially use either a sweep of rising sound intensity to judge their self-motion towards an object or conversely use a sweep of falling sound intensity to judge their motion away from an object. Whether the sweep is rising or falling the listener must judge both the change in intensity across the sweep, and the temporal span of the sweep. Studies indicate that sweeping intensities are misperceived so that the sound intensity at the end of the sweep is judged differently than when the final sound intensity is presented alone. Although there is ongoing discussion as to whether the induced fading is greater for rising sound intensity as opposed to falling sound intensity, both phenomena affect the perception of self-motion. This paper presents a series of experiments that examined self-motion perception with auditory cues. Results confirm the finding of decruitment for a sweeping broadband sound source that decreases at various rates of acceleration. Furthermore, the phenomenon of decruitment was greatly diminished at higher accelerations indicating that this phenomenon is likely correlated to the lowest rate at which listeners can perceive a change in intensity.