Investigating mechanisms involved in vestibular substitution

点击翻译按钮获取中文摘要

Interactions between the vestibular and other sensory systems (vision, somatosensory and auditory) are crucial to several functions such as gaze stabilization, postural control and body representation. When one of the senses is altered, a phenomenon of compensation allows to recover, at least in part, functions associated with the impaired sensory system. Vestibular compensation is based on several concepts such as restoration, habituation and adaptation. Adaptation comprise sensory substitution which relies on the use of intact sensory systems to compensate the reduced vestibular input. The reflexes and perceptual functions associated with the vestibular system offers a unique window to study sensory substitution as most of these functions involve multisensory input. Although some studies suggest that sensory substitution is effective for some individuals, a high degree of inter-individual variability is observed which yet undermines the generalization of the results. It becomes therefore imperative to further develop fundamental knowledge related to the interactions between the vestibular and other sensory systems to better understand this phenomenon and ultimately optimize sensory substitution. The long-term goal of this research program is to reveal the contribution of non-vestibular senses on vestibular reflexes and perceptual functions. In the next five years, this program will aim at studying the mechanisms governing audio-vestibular and somatosensory-vestibular interactions on body representation in both healthy and audio-vestibular lesioned individuals. Studying both healthy and audio-vestibular impaired individuals will deepen our knowledge of the mechanisms involved in sensory substitution by observing the extent of plasticity in the vestibular system. To complete the proposed set of studies, we will use electrical vestibular stimulation, biomechanical analysis (motion capture, force platform), behavioral and perceptual methods. The results stemming from this proposed program will not only provide essential knowledge required to pursue investigations on mechanisms involved in vestibular plasticity, but will also provide fundamental concepts on vestibular substitution to develop various technologies to optimize sensory substitution.