Gaze control and vestibular-cervical-ocular responses after prolonged exposure to microgravity.

Background: Microgravity does not affect visual function directly. However, because of the altered afferentation from vestibular, support, and tactile-proprioceptive systems, it could lead to disturbances in visual tracking and inhibit the cosmonaut's activity. Therefore, it is necessary to obtain quantitative evaluations of spaceflight effects upon gaze control and vestibular-cervical-ocular responses.

[A computerized method for the combined evaluation of otoneurological and non-pharmacological correction of vestibulo-sensory and oculomotor disturbances].

Methodology and a new <> hard/software complex (HSC) have been developed jointly by the Institute of Biomedical Problems, <> and <> Companies to be used in vestibulometric, otoneurological, and psychophysiological tes-ting with synchronous registration and in the analysis of head movements, various types of nystagmus, and all forms of visual pursuit. The complex is intended for the expert/diagnostic evaluation, prognosis, and monitoring of the vestibular function, intersensory interactions, and eye pursuit movements as well as for teaching correction and elimination of unfavourable perceptive and vestibular-sensorimotor responses by developing a fixation reflex during exposure to visual and dynamic stimuli. The <> HSC was tested during pre- and post-flight observation of astronauts, under simulated and clinical conditions, as well as in monitoring the functional status of athletes engaged in various sports.

[Pursuit function of the eye during 7-day dry immersion without and with a support stimulator].

A computerized comprehensive investigation of the oculomotor system was performed following dry immersion of 12 human subjects deprived of or provided with support afferentation stimulation. The purpose was to determine effects of weak proprioceptive, tactile and support afferentation on the eye pursuit parameters and significance of the support input for the ocular function. Individual and general characteristics of spontaneous and induced oculomotor reactions were described and effectiveness of the eye tracking correction by stimulation of foot support afferentation during immersion was evaluated.