Influence of age on relative contribution of sensory systems to control of vertical stance in healthy subjects

The influence of the age factor on the contribution of the vestibular, visual, and proprioceptive sensory systems to the function of spatial orientation was assessed using the stabilometry method (ST-150, Mera, Moscow, Russia) during the vertical stance of a healthy person (N = 69, from 20 to 83 years old, of which 42 women and 27 men). Three age groups of subjects were examined: I (young, 20–25 years old, n = 37), II (middle-aged, 44–64 years old, n = 17 people), and III (elderly and old, 65–83 years old, n = 15). The subjects performed the Romberg test (stand with closed eyes) and postural stability (standing on a hard and soft surface) and a combined test (Romberg test + postural stability). This made it possible to compare the stabilometric parameters (the length and speed of the trajectory and the area of movement of the common center of pressure (COP)) under four conditions: 1) standing with eyes open on a stable surface (SS – EO), 2) eyes closed on a stable surface (SS – EC), 3) standing with eyes open on a thick layer of unstable surface (foam) (US – EO), and 4) eyes closed on a thick layer of unstable surface (foam) (US – EC). To calculate the contribution of sensory systems to the function of maintaining balance in a vertical stance, a formula was used. An increase in the length of the COP trajectory with increasing age was revealed. At the same time, only an insignificant change in the relative contribution of sensory systems to the parameters of the stabilogram was noted in middle-aged and older people compared to young people.