1986 Fiscal Year Final Research Report Summary
Initiation of voluntary movement and cerebro-cerebellar neuronal circuit
| Project/Area Number |
59440023
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (A)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
Neurophysiology and muscle physiology
|
|---|
| Research Institution | Kyoto University |
|---|
Principal Investigator |
SASAKI Kazuo Faculty of Medicine, Kyoto University Professor, 医学部, 教授 (20025539)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
MIZUNO Noboru Faculty of Medicine, Kyoto University Professor, 医学部, 教授 (10025596)
GEMBA Hisae Faculty of Medicine, Kyoto University Lecturer, 医学部, 講師 (00108987)
|
|---|
| Project Period (FY) |
1984 – 1986
|
| Keywords | Voluntary Movement / Cerebrocerebellar Neuronal Circuit / Local Cooling / Cortical Field Potential / サル |
|---|
| Research Abstract |
Mechanisms of initiation, control and learning of voluntary movements were investigated by using monkeys (Macaca fuscata). They were trained with visually-initiated, reaction-time hand movements and field potentials in the cerebral cortex and the cerebellar cortex associated with the movement were recorded and analysed with electrodes chronically implanted in these cortices. Also a local cooling method was applied to different areas of the cerebral cortex, and changes of the movement and cortical field potentials were explored during the cooling. Results will be summarized as below.
1. Characteristic field potentials prior to the movement were recorded respectively in the prefrontal, premotor, motor, somatosensory, prestriate, striate cortex etc. Increasing activities of the prefrontal, especially "prearcuate", and the premotor cortices appeared to correlate to "recognition learning" associating the visual stimulus to the movement. Recruitment of the cerebro-cerebellar interaction was a
… More
ttributed to attaining "skill learning" improving the timing of reaction-time movement.
2. Chronic recording from the cerebellar cortex, particularly the crus <II> of the cerebellar hemisphere, revealed that mossy fibre responses are induced at a latency of about 50 ms after the onset of visual stimulus. This is consistent with the assumption that the prefrontal and premotor cortices activate the cerebellum and in turn excite the motor cortex to execute the movement. The mossy fibre response was found to increase in accordance with the learning processes in agreement with the results of field potential analyses in the cerebral cortical areas.
3. Temporal local cooling of the forelimb motor cortex resulted in weakness and slowness of the reaction-time movement on the contralateral side. Analyses revealed that the compensatory motor function of the somatosensory cortex contributes to the execution of the movement during the motor cortex cooling although weak and slow.
4. Local cooling of the premotor cortex dissociated the aquired visuo-motor integration, and also made reaction times longer and more variable. The prearcuate area cooling induced only the latter effect of the premotor cortex cooling. The higher integrative function of other areas in the prefrontal cortex was investigated and results inspiring further studies were obtained. Less
|
