- 著者
- Naoki Kado Masanori Ito Toshiaki Suzuki Hiroshi Ando
- 出版者
- The Society of Physical Therapy Science
- 雑誌
- Journal of Physical Therapy Science (ISSN:09155287)
- 巻号頁・発行日
- vol.24, no.10, pp.949-952, 2012 (Released:2012-12-28)
- 参考文献数
- 20
- 被引用文献数
- 4 3
[Purpose] This study evaluated the effects of voluntary arm movements performed at various difficulty levels on the excitability of spinal motor neurons in the contralateral arm using F-wave analysis. [Subjects] A total of 20 healthy volunteers participated in this study after giving their written informed consent. [Methods] With the subject seated on a chair, F-waves were elicited from the right abductor pollicis brevis during movement tasks performed by the left arm. The tasks were repetitive movements between two targets placed 20 cm apart on a desk. The subject was instructed to accurately touch the targets with the tip of a pen. In order to adjust the difficulty level, the size of the targets was changed as follows: 5 cm × 15 cm (width × length) for task 1, 0.5 cm × 15 cm for task 2, and 0.25 cm × 15 cm for task 3. The control task was to remain in the sitting position on the chair. [Results] The amplitude ratio of F/M significantly increased during tasks 2 and 3 compared with that during the control task. [Conclusion] Voluntary arm movements performed at a high difficulty level increase the excitability of spinal motor neurons in the contralateral arm.
- 著者
- Yuki Fukumoto Yoshibumi Bunno Toshiaki Suzuki
- 出版者
- The Society of Physical Therapy Science
- 雑誌
- Journal of Physical Therapy Science (ISSN:09155287)
- 巻号頁・発行日
- vol.28, no.12, pp.3416-3420, 2016 (Released:2016-12-27)
- 参考文献数
- 11
- 被引用文献数
- 4 6
[Purpose] This study aimed to examine the effect of motor imagery on the accuracy of motion and the excitability of spinal neural function. [Subjects and Methods] Thirty healthy volunteers (males, 15; females, 15; mean age, 20.3 ± 1.0 years) were recruited. F-waves was recorded at rest, while holding a sensor, and while using motor imagery. Next, subjects learned 50% maximum voluntary contraction. The pinch force was measured without visual feedback before and after motor imagery. F-waves were analyzed with respect to persistence and the F/M amplitude ratio. Correction time and coefficient of variation were calculated from the pinch force. [Results] Persistence and F/M amplitude ratio ware significantly higher in the holding sensor and motor imagery conditions than in the resting condition. In addition, persistence under motor imagery was significantly higher than that in the holding sensor condition. No significant differences were observed in relative values of correction time and coefficient of variation between the two pinch action conditions. The pinch force in task 2 approximated a more authentic 50%MVC than that in task 1. [Conclusion] Motor imagery increases the excitability of spinal neural function, suggesting that it also affects accurate control of muscle force.