By Elizabeth Landau, CNN
(CNN) -- Driving over a pothole may not be a big deal for most people, but for Jeff Bell, it was a source of endless frustration.
Afraid that he had injured a person, he would drive back to each pothole again and again to check, and he lost a lot of time in the process.
"I knew that my behaviors made no sense. I knew that my thoughts that were triggering these behaviors made no sense, and yet I felt so helpless to do anything about it," he said.
Bell, a news anchor with KCBS Radio in San Francisco, California, now knows that his condition has a name: obsessive-compulsive disorder. He frequently speaks out about it and has written a memoir called "Rewind, Replay, Repeat."
Psychologists are debating where OCD belongs in relation to other psychiatric disorders, and whether certain symptoms are actually part of other conditions. The condition affects as many as 4 million Americans, according to the International OCD Foundation, for which Bell is a spokesman.
In a class of its own?
Currently, OCD sits with anxiety disorders in the Diagnostic and Statistical Manual of Mental Disorders, published by the American Psychiatric Association to help diagnose mental illness. The next edition will be released in 2012, according to the APA.
Many experts, such as Jonathan Abramowitz, professor of psychology at the University of North Carolina, Chapel Hill, believe OCD should stay with anxiety disorders. That's because people with the disorder tend to engage in repetitive behaviors to reduce anxiety.
There is mixed evidence based on brain scans that OCD has a separate biological mechanism, leading some psychiatrists to favor classifying it separately, Abramowitz said.
"We haven't exactly pinned down what might be the problem," he said.
Categorizing related symptoms:
Checking for evidence of harm done, as in Bell's case, is one of many manifestations of OCD. Some people are overly afraid of germs, while others are overwhelmed by thoughts of violence or sex, or fear that they have "sinned," and still others spend countless hours arranging objects, said Jeff Szymanski, executive director of the International OCD Foundation..." More