Cosmonauts spending a lot of time in space can face health issues like muscle atrophy, reduced bone density as well as harsh effects on their brain, as per a long researched study.
Very little information on how several brain tissues react to exposure to the microgravity is known, a researcher of the study said. Moreover, it also remains unclear till what level do the neuroanatomical alterations noticed until now persist after the cosmonauts return to Earth’s normal gravity.
The study reveals that varied changes are detectable in 3 main brain tissue volumes for around six months after a cosmonaut completes his/her mission. The study was conducted on 10 Russian cosmonauts, with cosmonaut having spent around 189 days on an average on the International Space Station (ISS).
Magnetic resonance tomography (MRT) was used by the researchers to capture an image of the brains of the cosmonauts, before and after the end of their long missions in the space.
Additionally, the researchers re-examined seven cohort members seven months after they returned from space. The MRT scanning conducted after their return back to the Earth showed that the grey matter volume of the brain lessened compared to the measurements taken before the launch of the space mission.
In the re-examination conducted by the researchers seven months afterwards, such an effect was reversed partly but was still detectable. In contrary to this, the cerebrospinal fluid volume within the cortex increased during the long exposure of the cosmonauts to the microgravity.
Also, the process was noticeable in the outside spaces of the brain just after they returned to the Earth, whereas the spaces of the cerebrospinal fluid returned to almost their normal size. The volume of the white matter tissue seemed to be quite unaffected when the researchers conducted research instantly after their landing.
The study is published in the New England Journal of Medicine.