Dynamics of Electrical Sensitivity of the Retina and Electrical Lability of the Optic Nerve in the 12-month International Experiment SIRIUS-23

The aim of the 12-month international experiment SIRIUS 23/24 was to evaluate the effects of long-term isolation conditions and exposure to stress factors on electrical sensitivity (ES) of the retina and electrical lability (EL) of the optic nerve (ON) in the ES&EL test in participants. On board the artificial station, monthly testing of the retinal ES and EL of the ON was carried out. The results obtained in this 12-month experiment confirm the patterns of changes in the retinal ES and the ON EL established earlier in the 8-month SIRIUS-21 experiment. It was shown that with short-term or moderate physical and psycho-emotional stress, the retinal ES can increase. A decrease in the threshold of the ES may also indicate individual physical and mental endurance of the crew members. It has been confirmed that the EL of the ON is more resistant to physical and psycho-emotional stress than the thresholds of the ES of the retina. Considering the relative stability of EL indices and the dynamics of EC thresholds, the EC&L test may be a useful method for assessing the individual endurance of crew members, the functional state of the papillomacular bundle of fibers of the ON in astronauts on orbital space stations, and identifying the risk of developing SANS during long-term interplanetary flights.

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