Purchase this article with an account.
Oliver Toskovic; Importance of proprioceptive and vestibular information for visual space anisotropy. Journal of Vision 2008;8(6):747. doi: 10.1167/8.6.747.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
In previous research we showed that in darkness, physically shorter distances towards the zenith are seen as equal to physically longer distances towards the horizon. It remained unclear, whether this difference in distance estimates, is a consequence of a shift in the position of the body, of the head, or of the eyes. In order to answer that question, three experiments were performed. In each experiment participants had the task to equalize distances of three rectangular lightning stimuli, on three different viewing directions. In the first experiment, those three directions were horizontal, tilted 30 degrees relative to the horizon, and tilted 60 degrees relative to the horizon. In the other two experiments, viewing directions were horizontal, tilted 45 degrees relative to the horizon and vertical. Participants in all three experiments performed estimates while sitting on the floor, in a dark room. In the first experiment there were 14 participants with their head and body fixed (using chin-rest), in the second there were 15 participants with their body and eyes fixed (using chair and special glasses with 1mm wide horizontal aperture), and in the third there were 16 participants with their eyes and head fixed (using special glasses and an automobile seat). Results first showed that for near distances, such as 1m, visual space is isotropic, and that anisotropy appears for distances over 3m. Data also showed that the head and body tilt elongates the visual space towards vertical direction (physically shorter distances towards the zenith are seen as equal to physically longer distances towards the horizon), but angular turns of the eye compress visual space towards vertical direction. According to that, we can conclude that the visual system, for distance estimates, uses additional information, proprioceptive (information from neck and eye muscles) and vestibular, but with different weights.
This PDF is available to Subscribers Only