In a NASA funded research, the US space agency is currently trying to understand changes in both brain structure and function in astronauts on broad the International Space Station (ISS) to establish the time it takes for them to fully recover after returning from their space mission. Past research and reports suggest that the astronauts have a difficult time in controlling their physical movements and carrying out any kind of mental tasks in microgravity. Many have reportedly experienced problems with balance and perceptual illusions – as if they’re switching between straight up and upside-down. NASA is making use of both brain imaging and behavioral assessments to effectively reach a conclusion.
Astronauts have to go through timed obstacle courses and are made to undergo spatial memory tests (where they’re asked to picture and manipulate a 3-dimensional shape) before and after spaceflight. The spatial memory tests are even carried aboard the ISS, along with several other tests like sensory motor adaptation tests and computerized exercises where they’re required to think and act simultaneously. These tests are executed after arriving aboard the station, mid-way and during the end of a six-month flight.
Principal investigator Rachael D Seidler, Director of University of Michigan’s neuromotor behavior laboratory, stated that they were observing the volume of different structures in the brain and the changes they are exposed to during spaceflight. For this they’re using functional MRIs, wherein the astronauts complete a task during the imaging and the researchers may observe the parts of brain utilized to complete the necessary task. As per Seidler, both behavioral assessment and brain imaging play an important role and help them identify the relationship between physical and behavioral changes. On Earth, he informs, one’s vestibular or balance system signals you how your head moves in gravity, but when in space, that gravitational reference is totally gone, thus resulting in perceptual illusions and it’s really difficult coordinating eyes and head movement. These complications could be of serious consequence to astronauts, especially when changing gravitational environments, say like landing on Mars. In such situations, astronauts are made to perform tasks like driving a rover and using regular tools, and they must be efficient enough to escape in a landing emergency.
These tests shall help researchers identify physical mechanisms behind these behavioral changes and how mush time it actually takes for their brain to return to its normal state. The findings could even shed light on whether the astronaut actually returns to ‘normal’ post-flight after the brain changes back, or whether the brain acclimatizes itself with the changes that it was exposed to in space.
Image source: Gravity (movie).