Discouraging space travel news

I knew prolonged periods of weightlessness were not good for bones, eyes and muscle:  not sure that I had heard before that it shrinks parts of brains too.   (Actually, this short explanation is kinda confusing):

Flying in space shrinks some regions of cosmonauts’ brains — an effect that persists long after crews come home.

Researchers know that spaceflight causes parts of the brain to swell and tilt, but Angelique Van Ombergen at the University of Antwerp in Belgium and her colleagues wondered precisely how time in orbit affects brain volume, especially well after the return to Earth. To investigate, the team studied brain scans from ten Russian cosmonauts before and after orbital stints of around six months.

About one week after the cosmonauts returned to Earth, some portions of their brains showed a larger volume of cerebrospinal fluid — which cushions and cleanses the brain — than before the flight. By contrast, certain regions of the brain’s grey matter, containing neurons that produce signals, shrank over the same time period. Most of the grey matter recovered in the following seven months, whereas the brain’s white matter, which transmits neural signals, withered in the months after landing.

The authors say that brain-volume changes might help to explain medical problems related to long-term space travel.

Another report about the study says this:

What these changes mean for the cosmonauts is still an open question. "However, whether or not the extensive alterations shown in the gray and the white matter lead to any changes in cognition remains unclear at present," study co-author Dr. Peter zu Eulenburg, a neurologist and professor of neuroimaging at Ludwig-Maximilians-Univeristat München in Germany, said in a statement.

Sort of ironic if Earth's best and brightest take off for Mars, but are too dumb to remember how to assemble their habitats by the time they arrive.