Galvanic vestibular stimulation: from cellular mechanisms to behavioral responses

Stimulation of vestibular peripheral pathways with ‘direct current’, also called Galvanic Vestibular Stimulation (GVS) has been increasingly used in research and as a non-invasive method in the clinic. The goal of the present proposal is to improve GVS effectiveness through local application of drugs in the vestibular sensory organs. We propose a multifaceted approach to investigate these effects at the cellular and behavioral levels. We will use an in vitro preparation of the vestibular sensory epithelium to study the effect of local galvanic stimulation on nerve terminals before and after application of specific antagonists of potassium channels to modify the response properties of afferents. In parallel, we will investigate whether local application of the above drugs can increase the effect of GVS in generating eye movements, particularly at higher frequencies of sinusoidal stimulation, suggesting that it can generate a better vestibulo-ocular reflex at these frequencies if used clinically. The results of these studies will have significant implications for developing more precise and efficient therapeutic approaches by GVS.