Effects of vibratory stimulation on auditory induced self-motion
Poster Presentation

Aleksander Väljamäe
Dept. of Signals and Systems, Chalmers University of Technology

Pontus Larsson
Dept. of Applied Acoustics, Chalmers University of Technology

Daniel Västfjäll
Dept. of Applied Acoustics, Chalmers University of Technology

     Abstract ID Number: 122
     Full text: Not available
     Last modified: March 21, 2005

Abstract
Creating a sense of illusory self-motion (vection) is crucial for many Virtual Reality (VR) applications, where optimized multi-modal stimulation is an essential, but often neglected, component. Extending our previous findings on auditory-induced vection (AIV), we investigated how additional stimulation of vestibular modality can enhance self-motion sensation. Our hypothesis was that a low level vibratory stimulation, which can be elicited either by mechanical shakers or low frequency sound, might affect vestibular system input and therefore reduce conflict between modalities and enhance AIV. In the first experiment on rotational AIV, we have found that both infrasound (15 Hz) and vibrations significantly increased AIV sensation intensity. In the second experiment on translational AIV, mechanic vibration but not low frequency sound (40 Hz) affected self-motion reports. Additionally, two vibratory stimulation levels revealed that the AIV ratings decreased for the high level vibrations, where instead of the desired auditory-vibrational combination two separate streams were perceived. Results suggest that the optimal level of cross-modal enhancement is important for VR applications with complex sensory stimulation.