BODY REACTION TIMES TO EIGHT DIFFERENT DIRECTIONS IN THE EGO-CENTRIC SPACE

Abstract

Disjunctive reaction times (RT's) to eight different directions in the ego-centric space were measured in adult subjects standing upright. Two major findings were: 1) RT's to the forward direction were longer than those to other directions. 2) RT's to the left side were better than those to frontal right side, but this difference was not shown in the back ward direction. From these findings, it is suggested there might be a phenomenon of "anisotropy of space" for our sensory-motor adjustment to environment. The mean scores of eight RT's of different directions were obtained and their validity was examined as an index of the individual preparedness to its environmental change. The mean RT of college male students was 0.813 seconds. It was found that these RT's were better in some athletic club members who usually need quick decision making of this type. From additional experiments, it was also found that RT improved with child developmental stage and retardation was observed after middle age, and that RT was related with W/H ratio in youth and adult subjects. From these results it is possible to state that RT is a useful indicator of the individual preparedness to directional change of body.