OCD, also known as obsessive-compulsive disorder, often plagues a person with persistent, unwelcome thoughts or images, or by the urgent need to engage in certain rituals. Common rituals that patients with the condition often engage in include frequent handwashing, counting, and cleaning fanatically. Depression or other anxiety disorders may also accompany the condition, and some people with obsessive-compulsive disorder may have eating disorders, too.
People with obsessive-compulsive disorder (OCD) suffer intensely from recurrent, unwanted thoughts (obsessions) or rituals (compulsions) that they feel they cannot control. Rituals such as handwashing, counting, checking something, or cleaning are often performed with the hope of preventing obsessive thoughts or making them go away. Performing these rituals, however, provides only temporary relief, and not performing them markedly increases anxiety.
If left untreated, obsessions and the need to perform rituals can take over a person's life. OCD is often a chronic, relapsing illness.
The cause or causes of OCD are not known. However, there is growing evidence that the condition represents abnormal functioning of brain circuitry, probably involving a part of the brain called the striatum. OCD is not caused by family problems or by attitudes learned in childhood, such as an inordinate emphasis on cleanliness or a belief that certain thoughts are dangerous or unacceptable.
Brain imaging studies using a technique called positron emission tomography (PET) have compared people with and without OCD. Those with OCD have patterns of brain activity that differ from people with other mental illnesses or people with no mental illness at all. In addition, PET scans show that in patients with OCD, both behavioral therapy and medication produce changes in the striatum. This is graphic evidence that both psychotherapy and medication affect the brain.