Neuronal mechanism generating vertical eye position signals.
Project/Area Number |
03670050
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Research Category |
Grant-in-Aid for General Scientific Research (C)
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Allocation Type | Single-year Grants |
Research Field |
Neurophysiology and muscle physiology
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Research Institution | University of Tsukuba |
Principal Investigator |
YOSHIDA Kaoru Univ. Tsukuba, Inst of Basic Med. Sci. Associate Professor, 基礎医学系, 助教授 (50111373)
|
Project Period (FY) |
1991 – 1992
|
Project Status |
Completed (Fiscal Year 1992)
|
Budget Amount *help |
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1992: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1991: ¥1,700,000 (Direct Cost: ¥1,700,000)
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Keywords | vertical eye movement / eye position / vestibular nucleus / interstitial nucleus of Cajal / カハ-ル間質核 / 舌下神経前位核 |
Research Abstract |
The vestibular nucleus (VN) and the interstitial nucleus of Cajal (INC) contain neurons with activity related to vertical eye movement. To examine a possible interaction between the two nuclei, projection of INC neurons to VN and vestibular input to these neurons were studied in the alert cat. Sixty-two INC neurons with activity related to vertical eye position were tested for the response to stimulation of the ipsilateral VN. Forty-one had a downward and 21 an upward on-direction (to be called downward and upward neurons, respectively). Thirteen of 41 downward neurons were antidromically activated following stimulation of the ipsilateral VN with thresholds 36 to 220 muA. None of 21 upward neurons showed antidromic responses. Histological study showed that the stimulation sites had been in the ventral part of VN at the level of the Vlth nucleus. All the downward INC neurons antidromically activated from VN responded orthodromically to stimulation of the contralateral vestibular nerve at disynaptic latencies (1.3 to 2.0 msec). We suggest that secondary VN neurons carrying vertical eye position signals make excitatory connections with contralateral downward INC neurons which in turn send the signal ipsilaterally to VN. This neural pathway may form an important part of the neural circuitry responsible for the generation of vertical eye position signals.
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Report
(3 results)
Research Products
(26 results)