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Comprehensive computerized oculomotor testing was used to investigate the vestibular function in 9 Russian members of ISS crews 3-9 on days 1 (2), 4 (5) and 8 (9) of return from long-term stay in microgravity (126 to 195 days). The vestibular function was assessed by the static otolith-cervical-ocular reflex, dynamic otolith-cervical-ocular reactions, vestibular reactivity, and spontaneous oculomotor activity. The postflight investigations revealed functional disorders in the peripheral (an increased vestibular reactivity, absent or damped otolith-cervical-ocular reflex), and central (spontaneous typical and atypical nystagmus, gaze nystagmus) vestibular analyzer. The pattern and extent of vestibular disorders after long-term exposure in microgravity were individual by character; however, some of the vestibular reactions, including disappearance or considerable damping of the static otolith-cervical-ocular reflex, exaggerated vestibular reactivity and spontaneous eye movements, displayed consistency.

The new soft- and hardware is intended to specifically test the eye-tracking profession in order to diagnose and monitor the ocular and related sensory systems. Oculography is used to investigate different forms, including spontaneous and evoked, of visual tracking by computer stimulation of the sensory inputs. The system validation was a part of the pre- and post-flight examination of Russian spacecrew members, and protocol of the 7-d dry immersion. As a result, demonstrated was a considerable degradation of the precision and velocity, and extension of time parameters after long-duration missions with differentiation of concurrent peripheral vestibular disturbances and central structural changes. Throughout the period of immersion, the parameters displayed diverse changes which rendered distinction between baseline and experimental data impossible. Comparative analysis of the post-flight and experimental data showed that the most marked deviations in the eye tracking function were peculiar to cosmonauts on return from long-duration space flight.

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. The pursuit function was tested before the experiment (baseline data), in 3 hrs. since the beginning of immersion, on day 5 in immersion, shortly after and on day 3 of the completion of the experiment. The group of subjects without support stimulation exhibited marked omnidirectional deviations in the eye tracking parameters throughout the whole period of the experiment. In the group of subjects provided with support stimulation these parameters were but little different from baseline values. To conclude, a support stimulator stabilized the pursuit function of the eye making it less variant. However, there was no uniformity in the subjects' reaction to stimulation which infers that the methods of improving the eye pursuit function should be personally "molded".

A Lusher test-based algorithm of the quantitative evaluation of the ability to perform under the conditions of determinant and stochastic stimuli was developed and validated in experiments with volunteered subjects.