Does the Controllability of the Body Schema Predict Equilibrium in Elderly People? Characteristics of Relationships from a Lifelong Development Perspective

Background: Equilibrium is a primary factor that describes and predicts elderly people’s falling and fear of falling. However, elucidation of the relationship between equilibrium and cognitive function and the influence of cognition function on equilibrium in elderly people is required. Methods: This study sought to illustrate the characteristics of the equilibrium function in elderly people, focusing on the vividness and controllability of the body schema as a cognitive function and analyzing its relationship with body sway (in the one-leg standing test with eyes open) from a lifelong development perspective. Movement distance and the outer area in body sway in the one-leg standing test with eyes open were measured for 139 participants including children, college students, and elderly people. In addition, the vividness and controllability of the body schema were measured using reaction times in a video game-style imaginary body movement test. Results: In the college students, both types of cognitive function were significantly correlated with equilibrium, indicating an association between these two variables. Moreover, different relationships between equilibrium and cognitive function were observed in children and elderly people. Therefore, equilibrium in the elderly people did not deteriorate to the extent that it reflected the characteristics of young children; rather, it was influenced by multiple factors that attributed to the deterioration of the motor organ while maintaining basic strategies continued from early adulthood. Conclusion: Specific outcomes could be achieved to maintain the health of elderly people via future examining of the relationship between equilibrium and cognitive function.