Get a Hold of Yourself, Man!/Real Life

"Grampa: You can push them out of a plane, you can march them off a cliff, you can send them off to die on some God-forsaken rock, but for some reason you can't slap them."
 * General George S. Patton once famously slapped a young soldier who seemed to be suffering from shell shock (it turned out later he had malaria). It almost ended his career, proving that this isn't a good idea to try for real.
 * As a side note, the soldier Patton slapped later said, "He was probably pretty well worn out himself." Combat can do strange things to people. Patton's popularity saved him.
 * It doesn't work if it is "shell shock" (PTSD) either. Anyone who's been in the Armed Forces can tell you that, combat experience or not. A person that far gone has usually spent themselves keeping a hold for as long as they have.
 * This was parodied during the extensive Patton movie pastiche in The Simpsons episode "Bart the General". Bart does it, but Grampa scolds him:


 * MythBusters tested this trope on their December 22, 2010 episode. Their result? Confirmed. While not up to control, all three testers did better in practical tests when frazzled and then slapped than when unslapped.
 * At least when the subject isn't suffering from PTSD, as above.
 * Depends, if the subject is already in a situation which can trigger a psychosis episode, it can actually snap them out of it. Largely due to the endorphins that get released from the sudden shock.
 * This is because being slapped activates the flight- or fight-response. PTSD is this response having caused too much stress leading to a mental breakdown, so activating it could actually make it worse.
 * In some sects of Zen Buddhism, a monk walks the room during meditation sessions with a light, flat stick. When a meditating monk loses his focus because he starts to get tired, he will lean forward to get a light slap between the shoulder blades with the stick, which triggers the reaction to make him fully awake again.