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Modulation of high-frequency vestibuloocular reflex during visual tracking in humans1. Humans may visually track a moving object either when they are stationary or in motion. To investigate visual-vestibular interaction during both conditions, we compared horizontal smooth pursuit (SP) and active combined eye-head tracking (CEHT) of a target moving sinusoidally at 0.4 Hz in four normal subjects while the subjects were either stationary or vibrated in yaw at 2.8 Hz. We also measured the visually enhanced vestibuloocular reflex (VVOR) during vibration in yaw at 2.8 Hz over a peak head velocity range of 5-40 degrees/s. 2. We found that the gain of the VVOR at 2.8 Hz increased in all four subjects as peak head velocity increased (P < 0.001), with minimal phase changes, such that mean retinal image slip was held below 5 degrees/s. However, no corresponding modulation in vestibuloocular reflex gain occurred with increasing peak head velocity during a control condition when subjects were rotated in darkness. 3. During both horizontal SP and CEHT, tracking gains were similar, and the mean slip speed of the target's image on the retina was held below 5.5 degrees/s whether subjects were stationary or being vibrated at 2.8 Hz. During both horizontal SP and CEHT of target motion at 0.4 Hz, while subjects were vibrated in yaw, VVOR gain for the 2.8-Hz head rotations was similar to or higher than that achieved during fixation of a stationary target. This is in contrast to the decrease of VVOR gain that is reported while stationary subjects perform CEHT.(ABSTRACT TRUNCATED AT 250 WORDS).
Document ID
20050000167
Acquisition Source
Johnson Space Center
Document Type
Reprint (Version printed in journal)
Authors
Das, V. E.
(Department of Veterans Affairs Cleveland, Ohio, United States)
Leigh, R. J.
Thomas, C. W.
Averbuch-Heller, L.
Zivotofsky, A. Z.
Discenna, A. O.
Dell'Osso, L. F.
Date Acquired
August 22, 2013
Publication Date
August 1, 1995
Publication Information
Publication: Journal of neurophysiology
Volume: 74
Issue: 2
ISSN: 0022-3077
Subject Category
Life Sciences (General)
Funding Number(s)
CONTRACT_GRANT: EY-06717
CONTRACT_GRANT: NAG9-571
Distribution Limits
Public
Copyright
Other
Keywords
NASA Discipline Neuroscience
Non-NASA Center

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