Interesting article in the Wall Street Journal: Silencing the Voice That Says You're a Fraud:

A physician starts playing a harsh mental tape in her head every time a new patient calls: What if I make the wrong diagnosis? I'm a terrible doctor. How did I get into medical school?

An executive loses his job and despite 25 productive years, he tells himself: I'm a loser. I can't provide for my family, and I'll never be able to again.

An eminent scholar is offered a top post in the Obama administration and his first reaction is: They must have made a mistake.

If these real-life examples sound familiar, you may have a caustic commentary running in your head, too. Psychologists say many of their patients are plagued by a harsh Inner Critic — including some extremely successful people who think it's the secret to their success.

An Inner Critic can indeed roust you out of bed in the morning, get you on the treadmill (literally and figuratively) and spur you to finish that book or symphony or invention.

But the desire to achieve can get hijacked by harsh judgment and unrelenting fear. "There's a healthy version and an unhealthy version," says Daniel F. Seidman, a clinical psychologist at Columbia University Medical Center in New York. In some cases, he says, "people may achieve a lot, but they are totally miserable about it."