The inexplicable collapse of a tennis phenom

To hit a 120-mph serve, a player must allow the body to do what it has been trained to do. Thinking mid-serve causes “paralysis by analysis,” an attack on performance by the prefrontal cortex, which, in an attempt to control closely synchronized neural activities and muscle twitches, instead sabotages them. “We all know how to shuffle down the stairs,” Beilock told me. “But if I ask you to think about how your knee is bending while you do it, there’s a good chance you’ll fall on your face.”