[Spectral Analysis of Sway of Human Body When Standing on Firm and Compliant Surfaces under Different Visual Conditions.].

The influence of different visual conditions on maintenance of vertical posture when standing on a firm and a compliant surface were compared. Motionless visual environment (MVE), closed eyes (CE) and virtual visual environment (VVE) were used as visual conditions. Displayed VVE included foreground and background.

[The Influence of Light Tactile Contact on the Maintenance of Vertical Posture under the Conditions of Destabilization of the Visual Environment].

We studied the influence of a light contact of the index finger with a stationary surface of external environment on the maintenance of upright posture in healthy subjects "immersed" in unstable virtual visual environment. Under these conditions, the subjects saw the screen with a visual scene consisting of foreground and background. The foreground represented a window of a room with adjoining walls; and the background plan--an aqueduct with the adjacent terrain.

[Errors in pointing under various body orientation relative to the gravity vector].

Errors in pointing to remembered target locations were measured in healthy subjects in upright, supine and prone positions, i.e. in three positions differing in body and arm movement orientation relative to the gravity vector.