The response of the sensorimotor cortex containing aberrant corticospinal neurons which project to ipsilateral spinal cord
Project/Area Number |
10680746
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Neuroscience in general
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Research Institution | Nagasaki University |
Principal Investigator |
FUJIMURA Koichi Nagasaki University School of Medicine, Physiology, Lecturer, 医学部, 講師 (10173460)
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Project Period (FY) |
1998 – 1999
|
Project Status |
Completed (Fiscal Year 1999)
|
Budget Amount *help |
¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 1999: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1998: ¥3,100,000 (Direct Cost: ¥3,100,000)
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Keywords | hemidecortication / remodeling / motor area / pyramidal tract / evoked potential / CSD / cerebellum / forelimb / 運動機能代償 / 多点同時記録 / 大脳誘発電位 / 大脳半球破壊 / 前肢運動 / 新生児ラット / 感覚運動野 / 小脳核刺激 / 前肢刺激 |
Research Abstract |
After unilateral ablation of the sensorimotor cortex in neonatal rats, the terminal distribution of the primary somatosensory distal forelimb area neurons within the motor cortex in relation to the distribution of corticospinal neurons by fluorescent tracer injections, and the electrophysiological responses to stimulation of the deep cerebellar nuclei and distal forelimbs were investigated in the right sensorimotor cortex of the rat. There found to be two or three nearly rostro-caudal bands of dense somatosensory projection fiber distribution separated by sparse spaces in the forelimb area of the spared motor cortex of the hemidecorticated rat, as well as of normal rat. The distribution of the pyramidal tract neurons projecting to contralateral cervical spinal cord and the ipsilaterally projecting pyramidal cells were extensively overlapped in the spared motor cortex. No significant evoked potential to ipsilateral forelimb stimulation was revealed by multichannel recordings on the surface of sensorimotor cortex of the hemidecorticated rat, whereas the stimulation in normal rat evoked a significant positive-negative potential in the middle portion between primary forelimb sensory area and the caudal forelimb motor area, which propagated medially to the motor area. The depth profile also revealed no significant potential deflection in the sensorimotor area of the hemidecorticated rat by the ipsilateral forelimb stimulation. Current source density analysis revealed no significant response for ipsilateral cerebeller stimulation, although small potentials appeared in broad area of the sensorimotor cortex in both control and hemidecorticated rats. The results indicate that the hemidecorticated rat should use its ipsilateral forelimb without at least its own peripheral feedback, and the distributed and overlapped neuron pool for each target of spinal cord is suggested to be constructed with independent feedback system.
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Report
(3 results)
Research Products
(6 results)