Reflective Eye Test

Digital Tablet Eye Vision Test for Space Missions [Reflective Eye Test (Ax-1)] on the Axiom-1 (Ax-1) private astronaut mission (PAM) evaluates visual function before, during and after spaceflight using well-tested software on a hand-held device. Results are expected to provide information on the effects of weightlessness on visual and other brain functions.

• Researchers are investigating the in-flight effects of weightlessness on visual function and recovery of visual functions.
• The Digital Tablet Eye Vision Test for Space Missions [Reflective Eye Test (Ax-1)] investigation uses rapid, well-tested functional vision test software on a digital tablet to enable quick and reliable evaluation of visual function before, during, and after the space mission.
• Results provide valuable information about changes in functional vision during space missions and may provide information on whether deterioration of vision occurs and how to prevent it in future.
• Changes in functional vision may provide information on other human functions related to brain functionality.
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Spaceflight-Associated Neuro-ocular Syndrome (SANS) has been identified as a condition that may develop in association with prolonged exposure to weightlessness. Reported symptoms include decrease in near vision and changes in the refractive error following return to Earth. Digital Tablet Eye Vision Test for Space Missions [Reflective Eye Test (Ax-1)] aims to measure the in-flight effects of weightlessness on visual function and the recovery of visual functions upon return to Earth. The study uses proven, well-tested digital tablet functional vision test software installed on a handheld device that enables rapid, reliable evaluation of visual function before, during, and after the space mission.

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One cycle of run of the complete eye vision exam takes up to 10 minutes. The exam assesses the impact of the extreme environment and space travel on functional vision. For the visual acuity task, the user is asked to respond on the tablet screen, specifying whether the direction of the letter E is pointing to the right or left. Feedback is provided on whether or not the answer is correct. The program is adaptive and continues until the user reaches the threshold level. However, the number of repetitions is limited. Four exams are conducted to asses the dynamic of the functional vision.

In the contrast sensitivity task, the target is a small grating (gabor patch). The user task is to identify whether the target appears or not. The program is adaptive, converging on the contrast threshold. There are three different target sizes.