We investigated the influence of the imagined muscle contraction strengths on spinal motor neuron excitability in healthy volunteers. F‐wave was used for assessing spinal motor excitability. The F‐waves during motor imagery (MI) under 10, 30, 50, 70, and 100% maximal voluntary contractions (MVCs) were compared. Furthermore, we investigated changes of the F‐waves during motor imagery for 5 min. Motor imagery under 10, 30, 50, 70, and 100% maximal voluntary contractions can increase spinal motor neuron excitability. However, the imagined muscle contraction strengths were not involved in changes of spinal motor neuron excitability. Additionally, spinal motor neuron excitability after 5 min from onset of motor imagery returned to the rest level. Thus, in clinical use of motor imagery, slightly imagined muscle contraction strength is enough for facilitating spinal motor neuron excitability. Also, duration of motor imagery needs to be considered.
Part of the book: Neurological Physical Therapy
Purpose: This study aimed to examine the effects of motor imagery on the excitability of spinal motor neurons and accurate motion. Subjects and Methods: About 30 healthy volunteers were recruited. F-waves were recorded at rest, while touching a sensor and motor imagery conditions. Also, the pinch force was measured before and after motor imagery. Furthermore, the subjects mastered the 50% MVC pinch force with learning times of 10 s, 30 s, 1 min, and 2 min beforehand. Results: Spinal motor neuron excitability with motor imagery after motor learning for 10 s, 30 s, 1 min, and 2 min was significantly increased as compared to other conditions. Accurate motion in the pinch task after motor imagery was better maintained than in the pinch task before motor imagery with motor learning times of 30 s and 1 min. However, with learning times of 10s and 2 min, the subject?s ability to sustain accurate motion in the pinch task after motor imagery was significantly decreased as compared to that of the pinch task before motor imagery. Conclusion: Motor imagery increases spinal motor neuron excitability. To maximally improve accurate motion using motor imagery, it is important to practice and master motor learning beforehand
Part of the book: Neurological Physical Therapy
Motor imagery can be helpful for the therapeutic approach for the patients who have difficulty in the actual motion. This chapter explains the following important six points for getting high-effective motor imagery based on the neuroscience. First, excitability of spinal motor neuron was increased by motor imagery. However, adding effect on breathing state, both expiration and inspiration phase on the relax respiration, does not influence the excitability of spinal motor neuron. Also, motor imagery increased the excitability of spinal motor neuron and cardiac sympathetic nerve activity. However, vividness of motor imagery was to converge a degree. Motor practice before motor imagery was important. Motor practice was appropriate for 30 s using intermittent visual feedback, and for doing motor imagery, time enough was 1 min. Adding motor imagery method was a recommended composite for kinesthetic and visual motor imagery. Unfortunately, motor imagery has few effects for the other hand. Therefore, motor imagery should be done on the ipsilateral side from the previous motor practice.
Part of the book: Somatosensory and Motor Research