One reason it's hard to shake off is what psychologists call the drive for self-verification—to have others reflect the beliefs we hold about ourselves. Most people are highly motivated to believe the best of themselves, and subtly or not so, they look for feedback from others to confirm these good feelings. But someone who's depressed will go out and seek negative feedback, verifying her own thoughts. In a 2000 study by Thomas E. Joiner, PhD, a psychology professor at Florida State University, the self-verification motive was so powerful that it overrode the pain of negative opinions. And a 2001 study coauthored by Joiner's colleague psychology professor Roy F. Baumeister, PhD, confirmed the idea that "bad is stronger than good": Bad feedback, bad parenting, and bad experiences are much more powerful than good ones. People remember the bad more vividly, process it more efficiently, and pay more attention to it. Bad impressions or stereotypes form more quickly, and negative feelings produce longer-lasting effects. So my brain tricks me into remembering more vividly the occasional cooking disaster (a moment of silence now for the leaden spinach gnocchi I once foisted on innocent guests) than the preponderance of delicious food I've cooked. Or the miserable period of my life when I was injured, couldn't exercise, and gained 10 pounds instead of the rest of my life when I've fit into skinny jeans.