Is It All In Your Head?' - A neurologist chronicles stories
It costs the American health care system twice that of treating diabetes. And yet, it's not really a disease. Psychosomatic illness, where your body acts as if it's sick but there isn't anything wrong, is common and also very misunderstood, according to a new book "Is It All in Your Head: True Stories of Imaginary Illness" (ph). In it, neurologist Suzanne O'Sullivan describes some of the extreme cases she has treated and what may be behind them.

So psychosomatic illness is a disorder in which people get real physical symptoms that cannot be explained by physical examination or medical tests. No disease can be found to explain them. And there is usually believed to be a psychological or behavioral cause....