You're not at your best when you're stressed. In fact, your brain has evolved over millennia to release cortisol in stressful situations, inhibiting rational, logical thinking but potentially helping you survive, say, being attacked by a lion. Neuroscientist Daniel Levitin thinks there's a way to avoid making critical mistakes in stressful situations, when your thinking becomes clouded — the pre-mortem. "We all are going to fail now and then," he says. "The idea is to think ahead to what those failures might be." TEDTalks is a daily video podcast of the best talks and performances from the TED Conference, where the world's leading thinkers and doers give the talk of their lives in 18 minutes (or less). Look for talks on Technology, Entertainment and Design -- plus science, business, global issues, the arts and much more. Find closed captions and translated subtitles in many languages at http://www.ted.com/translate Follow TED news on Twitter: http://www.twitter.com/tednews Like TED on Facebook: https://www.facebook.com/TED Subscribe to our channel: http://www.youtube.com/user/TEDtalksDirector