As missions for deep space exploration and space habitats are put on the agenda, astronauts need to withstand being tested by multiple stressors in confined and isolated conditions during such long flights, especially because in deep space exploration, problems such as signal delays make astronauts feel the anxiety of being far away from Earth and the psychological fear of deep space.

According to a series of experiments conducted recently on Earth and during current space missions aboard the International Space Station (ISS), NASA believes that monotony of vision, in particular, aggravates the crew's anxiety, irritability, and depression. Moreover, a large number of studies have also found that crew members on long-term missions on the Antarctic Space Simulation Station are extremely susceptible to psychological problems caused by visual monotony and monochromatic colors.