Modification of the Cervico-ocular Reflex by Canal Plugging
The cervico‐ocular reflex (COR) has a low gain in normal animals. In this study, we determined whether COR gain increases were specific to the low/midband frequency range, which is the range over which the angular vestibulo‐ocular reflex (aVOR) is compromised by plugging. The gain and phase of the y...
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Published in | Annals of the New York Academy of Sciences Vol. 1164; no. 1; pp. 60 - 67 |
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Main Authors | , , , , , , |
Format | Journal Article |
Language | English |
Published |
Malden, USA
Blackwell Publishing Inc
01.05.2009
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Subjects | |
Online Access | Get full text |
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Summary: | The cervico‐ocular reflex (COR) has a low gain in normal animals. In this study, we determined whether COR gain increases were specific to the low/midband frequency range, which is the range over which the angular vestibulo‐ocular reflex (aVOR) is compromised by plugging. The gain and phase of the yaw and pitch COR and aVOR were compared in normal monkeys and those with all six semicircular canals or only the lateral canal plugged. During experiments animals sat with the body fixed to a chair and the head fixed in space. The body was oscillated about body‐yaw and body‐pitch axes over a frequency range of 0.05–6 Hz, with amplitude <10°. For normal animals, both yaw and pitch eye velocities were compensatory to the relative velocity of the head with respect to the body. The gains were 0.1–0.2 at frequencies below 1 Hz and decreased to zero as stimulus frequency increased above 1 Hz. Canal‐plugged animals had COR gains close to 1.0 at low frequencies, decreasing to ≈0.6 at 0.5 Hz and to 0.2 for stimulus frequencies above 3 Hz. The phase of eye velocity was 180° relative to head‐re‐body velocity at frequencies below 0.5 Hz and shifted toward 270° as frequencies were increased to 4 Hz. This study demonstrates that adaptation of COR gain is tuned to a frequency range at which the aVOR is compromised by the canal plugging. |
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Bibliography: | ark:/67375/WNG-BGZ4VX6C-M ArticleID:NYAS03775 istex:8C184A254D8ADCBEEEB4D56E8F8E401192DBBF0F ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 |
ISSN: | 0077-8923 1749-6632 |
DOI: | 10.1111/j.1749-6632.2009.03775.x |