Vestibular Labyrinth Contributions to Human Whole-Body Motion Discrimination

Departments of Otology and Laryngology and Neurology, Harvard Medical School, and Jenks Vestibular Physiology Laboratory, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts 02114.
The Journal of Neuroscience : The Official Journal of the Society for Neuroscience (Impact Factor: 6.75). 09/2012; 32(39):13537-42. DOI: 10.1523/JNEUROSCI.2157-12.2012
Source: PubMed

ABSTRACT To assess the contributions of the vestibular system to whole-body motion discrimination in the dark, we measured direction recognition thresholds as a function of frequency for yaw rotation, superior-inferior translation ("z-translation"), interaural translation ("y-translation"), and roll tilt for 14 normal subjects and for 3 patients following total bilateral vestibular ablation. The patients had significantly higher average threshold measurements than normal (p < 0.01) for yaw rotation (depending upon frequency, 5.4× to 15.7× greater), z-translation (8.3× to 56.8× greater), y-translation (1.7× to 4.5× greater), and roll tilt (1.3× to 3.0× greater)-establishing the predominant contributions of the vestibular system for these motions in the dark.

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Available from: Adrian J Priesol, Dec 26, 2013
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