Comparison between vestibular responses to a physical and virtual reality rotating chair

Abstract

The integration of visual and vestibular information is crucial to maintain our static and dynamic postural stability. In this study, vestibular responses to two types of sensory input are compared: 1) physically-induced yaw rotation 2) a visually-induced replica of the physically-induced stimulus (virtual stimulus). Twenty-seven healthy participants (10 females) underwent the physical stimulus using a hydraulic chair. Next, the virtual stimulus was applied using a head-mounted display (HMD). The vestibular responses were simultaneously recorded from both ear canals by means of a non-invasive technique called Electrovestibulography (EVestG). From the recorded EVestG signal, six segments were selected (Background, Acceleration, Deceleration, Return-to-Center (RTC) Background, RTC-Acceleration, and RTC-Deceleration) and two features were extracted from each segment: 1) the action potential (AP) area of the average field potential (FP), and 2) the mean of the distribution of the time intervals between each 33 consecutive FPs (IH33 mean). AP feature showed an overall significant difference only between movement phases (segments) (P=0.003). Additionally, the IH33 mean feature resulted in a statistically significant difference between physical and virtual stimuli (P=0.014). These findings support the interlink between the visual and vestibular systems with the plausible impact of visual inputs on vestibular compensation and substitution.