I'm a bit skeptical about these findings 
. I mean, how can we trust that the MRI scans accurately measured brain changes due to microgravity? What's the sample size for the 26 astronauts? Is it a random selection or was it biased towards NASA's astronaut corps? How do they account for individual variations in brain structure and function?
Also, what exactly does "reversible" mean here? Are we talking about temporary cognitive fogginess that clears up after a week on Earth, or are there lasting effects that could impact astronauts' lives long-term? I need some concrete data and more research before I'm convinced this isn't just a minor effect of space travel
. Can they share their methodology and results in more detail? 
. I mean, how can we trust that the MRI scans accurately measured brain changes due to microgravity? What's the sample size for the 26 astronauts? Is it a random selection or was it biased towards NASA's astronaut corps? How do they account for individual variations in brain structure and function?Also, what exactly does "reversible" mean here? Are we talking about temporary cognitive fogginess that clears up after a week on Earth, or are there lasting effects that could impact astronauts' lives long-term? I need some concrete data and more research before I'm convinced this isn't just a minor effect of space travel
. Can they share their methodology and results in more detail?