MULTISENSORY SPATIAL PERCEPTION IN CONGENITALLY HEARING IMPAIRED: AUDIO-TACTILE CUES FOR ENHANCED ​SPATIAL UNDERSTANDING

We investigate multisensory and spatial perception in congenitally hearing-impaired adults, focusing on the integration of tactile feedback into auditory experiences. Using a vibrotactile device that translates spatialized auditory cues into fingertip vibrations via intensity-weighted mapping across four actuators, combined with Higher-Order Ambisonics, we enable reproduce three-dimensional spatial information through both audio and touch. We assess spatial motion perception, orientation confusions, audio-tactile binding in complex scenes, and music enjoyment. While hearing-impaired participants show markedly reduced auditory spatial tracking, tactile spatial motion perception is comparable to that of typically hearing individuals, with combined audio-tactile performance showing similar benefits. Auditory direction reversals are significantly reduced with tactile input, and participants demonstrate immediate audio-tactile binding in dynamic, multi-source environments despite no prior training. Music enjoyment is also enhanced. These findings reveal the amodal nature of spatial representations and challenge strict modality-dependent accounts of spatial development, demonstrating that externalized three-dimensional spatial understanding can rapidly emerge through touch even in the absence of auditory spatial experience. The results contribute to ongoing debates on nature versus nurture in sensory development and have important implications for theories of crossmodal plasticity, multisensory rehabilitation, and assistive technology.