DIFFERENCE IN LEVEL OF AUTOMATIZATION OF UPPER AND LOWER-LIMB MOVEMENTS

This study investigated differences in automatization level of upper a nd lower limb movements by analyzing degree of the interference betwee n upper and lower limb movements when the subjects performed transitor y upper or lower limb movement at will during periodic movement of the other limb. Nonfulfillment of the assigned limb tasks was only observ ed when the subjects performed transitory lower limb movement during p eriodic upper limb movement. This finding suggests that the automatiza tion level of upper limb movement is lower than that of lower Limb mov ement. Insertion of the transitory lower limb movement altered the cyc le of periodic movement of the shoulder joint more than periodic movem ent of the wrist joint. Whereas insertion of the transitory upper limb movement altered the cycle of periodic movement of the ankle joint mo re than that of stepping. These findings suggest that the automatizati on level of shoulder joint movement and ankle joint movement is lower than that of wrist joint movement and stepping, respectively. This stu dy also showed that the automatization of periodic limb movement was a ccompanied by a phenomenon in which the insertion timing of transitory limb movement was restricted to within certain time phases of periodi c limb movement resulting in minute interference.