Everyone has been there. You are about to get into an accident, your heart races, your mind is completely focused on the oncoming car, time seems to slow, your thoughts become crystal clear. It's a near-death experience that you never forget. Your "stress response" has helped you to survive.Here's another scenario: your boss is shouting at you, your kids are sick, bills are piling up, life is getting really stressful on a chronic basis, day after day, and... after a while, you can't think straight! Your mind is racing, you have trouble paying attention and focusing, memory is impaired, worries abound, you can't make decisions or you make bad decisions, and depression may set in. Now the "stress response" is impairing your brain.What's going on here??Let's go back to basic biology. Long ago...