American scientists have found that structural changes in the brain after a long stay in space can persist for years after returning. In particular, it relates to the pituitary gland: 6 of 11 the astronauts who took part in the study, this structure was deformed after the flight. In addition, all participants in the study were increased in the brain and circulating cerebrospinal fluid is one of the consequences of increasing intracranial pressure and causes impaired vision, write the scientists in the journal Radiology.
Prolonged stay in microgravity increases intracranial pressure. One of the most common consequence is swelling of the optic nerve and consequent visual impairment. The change in pressure also leads to structural changes in the brain and the current of the cerebrospinal fluid that scientists have repeatedly shown (1, 2). This, in turn, can be as one of the indirect causes of visual impairment, it can also have some additional negative consequences, in particular regarding cognitive functions.
However, it is unclear whether the changes caused by the stay in microgravity for a long time. Larry Kramer (Larry Kramer) from the University of Texas and the Laboratory study of vision and the cardiovascular system of NASA and his colleagues studied the effects of stays in space on the brain of astronauts on new sample: it included 11 people returning from long duration space flights. Citing data from NASA, the authors claim that only two people from the sample have participated in such studies.
All participants held a MRI-scan to the start of the flight, the next day after returning, and after a month, three months, six months and a year: scientists have focused on the volume changes of the brain and circulation of cerebrospinal fluid.
After the flight, the astronauts had an increase in volume of the brain and circulating fluid in an average 33 milliliter or two per cent. The changes remained even a year after the end of the flight: the volume was increased by 28 milliliters. In addition, the six astronauts had a slight deformity of the pituitary gland is Central to the endocrine system of the brain, and its size has on the average decreased from 5.9 to 5.3 mm.