Electroretinogram Changes in the Crew of the 12-month Isolation Experiment SIRIUS-23

The international experiment SIRIUS-23 studied the effect of long-term isolation in a closed space (hermetic object — artificial station), simulating an interplanetary flight with accompanying stress factors, on the bioelectrical activity of the retina.

The aim of the study was to evaluate changes in the different types of electroretinogram (ERG), and in visual evoked cortical potentials (VEP) in the participants of the 12-month experiment. Changes in ocular blood flow were also assessed using Doppler research

Methods. All diagnostic examinations were conducted before and during the week after the crew exited isolation (conditional “landing”). The results indicate the general stability of the most studied parameters after the end of isolation. A slight decrease in the amplitude of flicker ERG (F-ERG) to 30 and 12 Hz flickers and P50 and N95 components of transient pattern ERG (PERG) with characteristic changes in peak latency was revealed, which indicate a mild dysfunction of retinal ganglion cells and their axons without organic damage to the visual pathways. A positive trend towards an increase in the amplitude of the photopic negative response (PhNR) to a medium-strength stimulus and the amplitude of the P100 component of VEP to a pattern-reversal to a pattern-reversal chessboard stimuli after the crew exited isolation was found. A statistically significant increase in the peripheral resistance index and pulsatility index in the ophthalmic artery, central retinal artery and lateral posterior short ciliary arteries was recorded, which may indicate a change in vascular tone in the retinal and choroidal circulation system of the eye after a 12-month experiment.

1. Palinkas LA, Suedfeld P. Psychological effects of polar expeditions. Lancet. 2008;371(9607):153–163. doi: 10.1016/S0140-6736(07)61056-3.

2. Sadovnichiy VA, Amelyushkin AM, Angelopoulos V. Space experiments aboard the Lomonosov MSU satellite. Cosmic Research. 2018;51(6):427–433 (In Russ.).

3. Mogilever NB, Zuccarelli L, Burles F. Expedition Cognition: A review and prospective of subterranean neuroscience with spaceflight applications. Front Hum Neurosci. 2018;12:407. doi: 10.3389/fnhum.2018.00407.

4. Neroev VV, Zueva MV, Tsapenko IV, Bubeev YuA, Manko OM, Smoleevsky AE, Aleskerov AM, Gracheva MA. Functional Activity of the Retina and Visual Evoked Cortical Potentials in Simulation the Factors of Space Flight in Conditions of Four Month Isolation in a Hermetic Object with Artifi al Habitat. Annals of the Russian Academy of Medical Sciences. 2021;76(5):488–496 (In Russ.). doi: 10.15690/vramn1323.

5. Robson AG, Frishman LJ, Grigg J, Hamilton R, Jeffrey BG, Kondo M, Li S, McCulloch DL. ISCEV Standard for full-field clinical electroretinography (2022 update). Doc Ophthalmol. 2022;144(3):165–177. doi: 10.1007/s10633-022-09872-0.

6. Frishman L, Sustar M, Kremers J, McAnany JJ, Sarossy M, Tzekov R, Viswanathan S. ISCEV extended protocol for the photopic negative response (PhNR) of the full-field electroretinogram. Doc Ophthalmol. 2018;136(3):207–211. doi: 10.1007/s10633-018-9638-x.

7. Zueva MV, Neroev VV, Tsapenko IV, Sarygina OI, Grinchenko MI, Zaitseva SI. Topographic diagnostics of retinal function disorders in rhegmatogenous retinal detachment by the method of rhythmic ERG of a wide range of frequencies. Russian Ophthalmological Journal. 2009;1(2):18–23 (In Russ.).

8. Thompson DA, Bach M, McAnany JJ, Šuštar Habjan M, Viswanathan S, Robson AG. ISCEV standard for clinical pattern electroretinography (2024 update). Doc Ophthalmol. 2024;148(2):75–85. doi: 10.1007/s10633-024-09970-1.

9. Bach M, Brigell MG, Hawlina M, Holder GE, Johnson MA, McCulloch DL, Meigen T, Viswanathan S. ISCEV standard for clinical pattern electroretinography (PERG): 2012 update. Doc Ophthalmol. 2013 Feb;126(1):1–7. doi: 10.1007/s10633012-9353-y.

10. Luo X, Frishman LJ. Retinal pathway origins of the pattern electroretinogram (PERG). Invest Ophthalmol Vis Sci. 2011 Nov 1;52(12):8571–8584. doi: 10.1167/iovs.11-8376.

11. Odom JV, Bach M, Brigell M, Holder GE, McCulloch DL, Mizota A, Tormene AP. International Society for Clinical Electrophysiology of Vision. ISCEV standard for clinical visual evoked potentials: (2016 update). Doc Ophthalmol. 2016 Aug; 133(1):1–9. doi: 10.1007/s10633-016-9553-y.

12. Neroev VV, Tsapenko IV, Kotelin VI, Zueva MV, Manko OM, Aleskerov AM, Podyanov DA. Electroretinographic studies of the crew of the 8-month international experiment SIRIUS 20/21. Sensory systems. 2023;37(2):152–161 (In Russ.). doi: 10.31857/S0235009223020038.

13. Wieser MJ, Miskovic V, Keil A. Steady-state visual evoked potentials as a research tool in social affective neuroscience. Psychophysiology. 2016;53(12):1763–1775. https://doi.org/10.1111/psyp.12768.