An investigation of multisensory perception of surrounding space in aided congenitally hearing impaired

We tested auditory spatial motion localisation in congenitally hearing impaired adult users of bilateral cochlear implants, and other hearing assistive devices. The group showed severely impaired capabilities despite extensive device use, emphasizing the role of nature in sensory development. We then investigate whether the deficit is maintained for other sensory modalities, by using an in-house sensory substitution device that provides weighted vibrotactile cues on fingertips to induce 3D spatial motion perception. The performance was significantly higher, both in the combined audio-tactile task and the tactile task itself, with accuracy comparable to typically hearing subjects. With touch, we also showed considerably fewer front-back and right-left confusions. The rapid audio-tactile binding and availability of 3D space representation through touch, point to the significant role of nurture in spatial perception development and its amodal nature. The findings show promise towards advancing multisensory solutions for spatial hearing rehabilitation. Highlights- Auditory motion localisation is severely impaired in aided congenitally hearing impaired, supporting the role of nature towards spatial development; - Binding auditory and tactile information enhances auditory spatial performance, supporting the role of nurture; - Hearing impaired individuals perform 360{degrees} motion localisation through touch with accuracy similar to typically hearing; - Surrounding spatial representation never before experienced in congenitally hearing impaired is rapidly available through an alternate modality