Humans can utilize the other persons' knowledge as their own knowledge as a function of the mirror neuron. In this study, we examined whether knowledge of results (KR) is utilized for self-motor adjustment when a person is provided with others' adjustment motion, and what kind of motor information is transmitted between people. The participants performed a jumping height adjustment task involving a vertical jump. This task involved adjusting the target height (50% of the height of a maximum effort trial), with obtaining the KR for each trial. We conducted the task under the following two conditions: (i) individual condition (12 subjects), with one subject performing four trials; and (ii) group condition (12 groups), with four subjects performing one trial each, while they observed others' motions and shared their KR. We collected the data on ground reaction forces and coordinates of twenty body points. Under both conditions, participants gradually approached the target jumping height as the number of trials increased. When the transition of jumping height was approximated using a logistic curve, both waveforms were found to be similar. This finding demonstrates that the learning patterns of both conditions are similar, which means that others' KR is utilized in self-motor adjustment. Additionally, when examining the way of height adjustment, we found that the jumping height was adjusted by the “power”of the shoulder and hip joints under both conditions. Therefore, we considered that the KR, and the “power” of the joints corresponding to adjusted motion, were transmitted through observation, hence making the adjustment of jumping height possible. We concluded that motor adjustments are connected not only by the aspect of the behavior but also by the aspect of motor control. These outcomes can be applied to new motor learning methods for rehabilitation and can provide expert tips for human movement.
