Visual and Nonvisual Contributions to Perceived Ego-Motion Studied with a New Psychophysical Method

Article type: Research Article

Authors: Mesland, B.S.^{; *} | Wertheim, A.H.

Affiliations: TNO Human Factors Research Institute, Soesterberg, the Netherlands

Note: [*] Reprint address: B. S. Mesland, TNO Human Factors Research Institute, Kampweg 5, 3769 DE Soesterberg, the Netherlands.

Abstract: The perception of ego-velocity (PEV) during sinusoidal linear acceleration (otolith stimulation) is investigated with a psychophysical method proposed by Wertheim (1990;1). This method is based on the threshold for object motion perception measured during ego-motion. In a first experiment, PEV was measured both with and without illumination of the experimental room. It was shown that, for the particular frequency and amplitude of ego-motion used, PEV in the light approached physical ego-velocity, whereas in darkness PEV was significantly smaller than physical ego-velocity. In a second experiment the PEV was measured again without illumination of the experimental room. It was found that in response to a sinusoidal ego-velocity stimulus, PEV was sinusoidal as well with a gain of 0.8 and a phase-lead of 4° at 0.15 Hz.

Keywords: ego-motion, object-motion, otoliths, Filehne-illusion

DOI: 10.3233/VES-1995-5404

Journal: Journal of Vestibular Research, vol. 5, no. 4, pp. 277-288, 1995