You have just 250 milliseconds to catch a fall

You have about 1/10 of a second to catch a glass of water when you knock it over.

You have 1/4 of a second  to catch a fall. That's the minimum time the brain needs to regiater that your body's off-kilter and to do what it takes to avoid a tumble.

"Anything less than 250 milliseconds--you're probably not going to catch yourself," says Daniel Ferris, a University of Michigan professor of kinesiology. In a recent study on balance, Ferri's team homed in on the left sensorimotor cortex,

an area of the brain thought to be responsible for coordinating motion. When you realize you're falling, this region responds first, sending out the neural signals that set your body in motion to (ideally) restore stability--all within a quarter-second. Now that's what we call quick thinking. - Spirit Magazine, March 2014

(Thank to Susan Fink for this tidbit.)