Space madness-the term NASA originally coined to describe a psychotic episode it worried would beset one of its astronauts while on a mission-is only one risk to the health of astronauts.
Concerns over the possibility of a space madness onset warranted an official protocol whereby the astronaut would be restrained with duct tape and given a sedative. Neuroscientist Andrew Newberg suggests that space travel reshapes the way the human brain works. The normal activity of mood-altering hormones are inhibited by zero gravity, and hallucinations such as light flashes have been reported by numerous astronauts.
But gene-altering doses of radiation may be a more legitimate concern. There has yet to be a definitive answer as to how much the brains of astronauts are being mutated by radiation.