This book is following truth for the motor imagery effects. The motor imagery improves muscular strength, motor function, and gait speed and so forth. However, it is unclear whether motor imagery affects the ability to make an adjustment of motion. Add, the motor imagery was increasing the activation of the central nervous system. But, the excitability of spinal neural function has been obtained a variety of results such as increased, unchanged or decreased during motor imagery. The only consistent result is an increase in activation of the central nervous system, while the excitability of spinal neural function may not always increase. Therefore, this study aimed to examine the effects of motor imagery on the ability to make an adjustment of motion and the excitability of spinal neural function. Motor imagery was increased excitability of spinal neural function. But, motor imagery might not change the ability to make an adjustment of motion. It is indistinct that the disparate motor task or strength contraction has an effect on motor imagery in the same this study.