Difference in Level of Automatization of Upper and Lower Limb Movements.

Abstract

This study investigated differences in automatization level of upper and lower limb movements by analyzing degree of the interference between upper and lower limb movements when the subjects performed transitory upper or lower limb movement at will during periodic movement of the other limb.Nonfulfillment of the assigned limb tasks was only observed when the subjects performed transitory lower limb movement during periodic upper limb movement.This finding suggests that the automatization level of upper limb movement is lower than that of lower limb movement.Insertion of the transitory lower limb movement altered the cycle of periodic movement of the shoulder joint more than periodic movement of the wrist joint.Whereas insertion of the transitory upper limb movement altered the cycle of periodic movement of the ankle joint more than that of stepping.These findings suggest that the automatization level of shoulder joint movement and ankle joint movement is lower than that of wrist joint movement and stepping, respectively.This study also showed that the automatization of periodic limb movement was accom-panied by a phenomenon in which the insertion timing of transitory limb movement was restricted to within certain time phases of periodic limb movement resulting in minute interference.