What causes Obsessive Compulsive Disorder?

No one exact cause of Obsessive Compulsive Disorder has been identified; rather, researchers are investigating several theories to provide the basis for this disturbance.

Abnormal Levels of Serotonin

The most widely held theory regarding the cause of OCD is a problem with serotonin levels. Serotonin plays a role in many biological processes including mood, sleep, appetite, impulse control, aggression, and pain. It is believed that people with symptoms of OCD have abnormally low levels of serotonin.

Structural Brain Differences

Brain-imaging studies have demonstrated abnormalities in several parts of the brains of people with OCD symptoms. These include the thalamus, caudate nucleus, orbital cortex, and cingulate gyrus.

Autoimmune Diseases

Research has found that certain autoimmune diseases, such as Sydenham’s chorea, rheumatic fever, pediatric streptococcal infections (strep throat) and lupus, may cause Obsessive Compulsive Disorder. These occurrences are rare, and most cases of OCD manifest without such explanations.