"The researchers next hope to follow a group of people for a longer duration to determine if sitting causes the thinning and what role gender, race, and weight

"The researchers next hope to follow a group of people for a longer duration to determine if sitting causes the thinning and what role gender, race, and weight might play in brain health related to sitting." This is just a preliminary study. It´s too soon to get any conclusions. But, it´s a good starting point for a hypothesis. I will like to see the results of the final study, even that is going to take a long time. I have seen many times links between sedentary life and illness. But this one looks promising as tries to find a mechanism on why this happens at the brain level that may affect cognition. And yes, before doing a more expensive study, they asked 35 people for a preliminary study. You don´t spend a lot of money to try to prove something without first trying to disprove it on the cheap. Translation for developers: before spending a lot of time to test something you first do a smoke test. If it passes you invest the time to test it fully. Otherwise, you go back to writing code.