Multisensory effects on speed perception in a linear acceleration condition

Abstract

Much of driving task involves human sensory system and a wide range of perceptual processes. The most immediate aspects of the driving task are that driver must judge their speed that allows the driver to act appropriately within time available. For making precise judgements of speed, multiple sources of sensory information are used such as visual, vestibular, and somatosensory system. Previous research described that vestibular information is combined with other sensory signals for self-motion perception. Among all other sensory interactions, visual-vestibular interaction is the primary factor in self-motion perception. Vestibular-somatosensory interaction also has effects on self-motion perception. However, few studies take account of multisensory interaction between all three sensory modalities. In particular, multisensory effects on speed perception in linear acceleration condition has not been explored. Here we investigated the driver’s perception of speed in driving simulators depending on human sensory cues such as optic flow (visual system), galvanic vestibular stimulation (vestibular system), and vibrotactile stimulation (somatosensory system). We also explored the interaction between all three sensory systems to find multisensory integration effects on speed perception. Our results demonstrate that multisensory enhancement or depression on speed perception occur among three sensory modalities. Multisensory enhancement on speed perception occurs when visual and vestibular stimuli are combined. Also, we found multisensory depression on speed perception between vestibular and somatosensory system. The results of this study give an insight into how we can shift our focus from conventional vehicle dynamics in studying quality of driving, to incorporate sensory dynamics using different sensory stimuli in modelling.