Asked by: Finbar Murphy, Zambia
Our brains have obviously evolved to work in Earth’s gravity. Experiments on the International Space Station suggest that our brains have an internal model of how gravity works that we use to accurately predict where a ball will be when we move to catch it. In a weightless environment, the ball moves at a constant speed, instead of a constant acceleration, and so our reactions are slightly off. Gravity also affects the flow of blood through the brain; at accelerations beyond 5g, this begins to affect the brain’s electrical activity, producing patterns that resemble epileptic seizures.
Subscribe to BBC Focus magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun science facts.