抄録
Problem: The perception of one's own movement has been ascribed to the hunction of semicircular canals or muscular sensations by the physiological investigators, but it is possible to treat it from a different point of view, i. e., as relational phenomena between man and his Umfeld in a certain field.
Experiment I : The subjects were instructed to judge the direction of their movements during actual movements in various degrees of speed and directions in a elevator. They were requested to shut their eyes while experiment was going on.
Result: This condition of closed-eyes set forth a comparatively homogeneous optical Umfeld. And the given field for the bodily movement can be thought as somewhat vague one. Under these conditions the subject became very careful for his own body and his perception of movement seemed to be considerably determined by the degree of speed.
Experiment II: The subjects were to judge the movement phenomena while looking at the outer wall through a trapezoidal prism, by means of which the direction of apparent movement of the wall was changed in various angles (0°, 45°, 90°, 135°, 180°) from the actual one.
Result: In this case, the movement seemes to take place in a heterogeneous Umfeld. The subject was not very cautious for his own body, and his movement was mostly determined by the optical counter-direction of the movement of the outer wall. But when the accerelation was great, the course of apparent movement took the direction of the compound force of these optical and muscular sensations.
Experiment III. A: After a certian period of movement (about 5 sec.) with his eyes; closed, the subject was to look out through the prism set in various angles.
Result: When the change of the angle was great or the speed was high, the influence of accerelation was also great, while when the angle was small or the speed was low, the movement was almost entirely optically determined.
Experiment III. B: About 10 minuites after the movement began which was optically given through the prism, the speed was altered and the subject was requested to close his eyes.
Result: There appeared two cases. In the first case, the course took an intermediate direction between that of the accerelation and the course of the former movement. In the second, the course became intermediate only at the moment when the force was given and then it again returned to the former course.
Experiment IV: About 10 minuites after the lateral movement through prism began, the subject, while sitting on a pivot-chair, was to point the directions of movements in various angles made by rotation of the chair with eyes closed.
Result; When turned round by himself, there were two cases, namely the subject pointed either the direction adhering to the elevator or the direction adhering to himself.
When turned round by others, there were also two cases, namely the subject pointed either a certain direction which was just a bit nearer to the direction of rotation from that of the elevator or always the direction adhering to himself.
Conclusion: Under these experimental conditions the perception of one's own movement seems to consist in the reversion of one's own Umfeld. In a comparatively homogeneous optical Umfeld, the determination of its reversion is effected by the force given on his body, while in a heterogeneous optical Umfeld, the determination of the reversion, seems to be carried out optically.
