Stress, isolation and depression are all common occurrences when you're a human stuck in a tiny space capsule for prolonged periods of time.
Few people ever get to experience space exploration, but for those who do, it may come with psychological consequences.
Even before humankind ever reached outer space, issues with space travel were raised by two psychiatrists in 1959. They believed any astronaut who left Earth could experience severe separation anxiety and suicidal thoughts.
Hallucinations are commonplace in space, as is abnormal brain activity causing astronauts to act out.
More problematic is how each individual in a space crew handles the daily stresses that come from being away from Earth for long periods of time.
This has grown in importance now that NASA has set its sights on Mars, which would require years in space.
Recent tests revealed what 520 days of confinement and isolation did to a six man crew in the Mars500 project.
The stress took a toll, and those most affected became argumentative leading to conflict. Sleep cycles were disrupted, and one man suffered from depression.
Studies have also found that the human brain may work differently in space with attention spans, multi-tasking, problem solving and coordination all affected.
The zero-gravity environment may also play a role in blood flow, which in turn affects how oxygen gets to the brain.
Any workplace involving stress, loneliness and a difficult environment is enough to affect anyone, whether they're on this planet or off it.
