Effect of a without conscious motor imagery strategy on the excitability of spinal nerve function

Abstract

This study investigated the effects of different methods of motor imagery on spinal motor nerve function. The motor imagery strategy was determined by a preliminary questionnaire on the strategy of free imagery. Based on the preliminary questionnaire results, the F-wave of the unselected imagery strategy was compared with those of free imagery. Nine healthy individuals (mean age, 21.7 years) participated in this study. We investigated the excitability of spinal motor nerve function during a motor imagery task. The motor imagery adjusted the pinch motion using the non-dominant thumb and index finger to 50% maximal voluntary contraction. The F/M amplitude ratio observed during free imagery was significantly higher than that observed during rest imagery, but there were no significant differences between the other conations. This suggests that the excitability of spinal motor nerve function changes with the content of the imagery during motor imagery or the number of contents of motor imagery. Moreover, motor imagery combined with muscle contraction and sensory imageries increased the excitability of spinal motor nerve function.