The race to explore and tour Space, the final frontier for humankind, is getting competitive with more and more nations joining the race. Yet there is need for caution as a recent study reported in sciencedaily.com suggests that those engaging in frequent and/or longer space travels should wait for a minimum three years to enable the physiological changes in their brain to come back to normal.

The scientists made this suggestion after closely studying the brain scans of 30 astronauts which were taken before and after their space travel. Out of the 30, eight had travelled on two-week missions, 18 on six-month ones while four had spent nearly one year in space.

As per details and findings of their study which have been published in Scientific Reports, the ventricles of the brain swell perceptibly in the case of those who finish missions that are long – for a minimum six months. To fully recover from this, a period of not less than three years is required.

The space in the brain which is filled with cerebrospinal fluid is called ventricles and it plays an important role. It protects, nourishes, and removes waste from the brain. The fluids in the body are properly distributed through certain mechanisms but when gravity is absent, the fluid moves upward. This pushes the brain higher within the skull resulting in expansion of the ventricles.

Talking about the study, its author Rachael Seidler who is Professor of Applied Physiology and Kinesiology at the University of Florida said: “We found that the more time people spent in space, the larger their ventricles became. Many astronauts travel to space more than one time, and our study shows it takes about three years between flights for the ventricles to fully recover.”

Seidler added that on the basis of the studies done till now it was found that ventricular expansion is the most enduring change in the brain that is visible due to spaceflight. “We don’t yet know for sure what the long-term consequences of this is on the health and behavioural health of space travellers, so allowing the brain time to recover seems like a good idea,” she observed.

The expansion of the ventricular gradually lessened after six months, the authors of the study said. Commenting on this aspect, Seidler said: “The biggest jump comes when you go from two weeks to six months in space. There is no measurable change in the ventricles’ volume after only two weeks.”

For those keen on touring space, a shorter stay spells better as it seems to cause less or little changes in the brain. At the same the levelling off ventricles after six months also spells well for astronauts. “We were happy to see that the changes don’t increase exponentially, considering we will eventually have people in space for longer periods,” Seidler said.

The study was funded by the National Aeronautics and Space Administration and is sure to impact planning of space travel in the future.