Journal des nouvelles physiothérapies

Abstrait

Effect of Motor Imagery After Motor Learning for 30 sec on Excitability of Spinal Neural Function and its Impact on Accurate Control of Muscle Force

Yuki Fukumoto, Yoshibumi Bunno and Toshiaki Suzuki

This study aimed to examine the effects of motor imagery on the excitability of spinal neural function and accurate control of muscle force. In total, 30 healthy volunteers (15 men and 15 women; mean age, 21.1 ± 1.2 years) participated in the study. The methodology involved recording F-waves under resting conditions with a touching sensor. Also, the subjects learned to maintain the 50% maximum voluntary contraction (MVC) value of the pinch by viewing a meter display for 30 sec. Next, the pinch force was measured for 10 sec without using visual feedback (1st trial of pinch task). Subsequently, the subjects engaged in motor imagery and the F-waves were recorded. Finally, the pinch force was measured again, as in 1st trial of the pinch task (2nd trial of pinch task). In the control group, the subjects did not use motor imagery on similar processes as in the motor imagery condition phase from different days. F-waves were analyzed with persistence. Correction time and the 50% MVC error were calculated from the pinch force. Persistence was more increased under motor imagery than in the resting and touching sensor. In addition, no significant differences were observed in correction time and the 50% MVC error in the motor imagery group. But in the control group, correction time was decreased and the 50% MVC error was increased in the 2nd trial of pinch task as compared to the 1st trial. In conclusion, motor imagery after motor learning for 30 sec increased spinal neural excitability function. Moreover, motor imagery might allow accurate control and maintenance of muscle force.