Tales of some great shock or fright suddenly turning a person's hair white go back thousands of years. Learn what researchers think is really going on -- and how our hair normally goes grey and white -- in today's episode of BrainStuff, based on these articles: https://science.howstuffworks.com/science-vs-myth/everyday-myths/can-hair-turn-white-overnight.htm; https://health.howstuffworks.com/wellness/aging/aging-process/stress-gray-hair.htm