The exact cause of obsessive-compulsive disorder remains unknown. A number of theories exist concerning the root cause of obsessive-compulsive symptoms, ranging from brain chemical imbalances and physical brain abnormalities to a rare condition known as PANDAS syndrome.
Serotonin and Obsessive-Compulsive Disorder
Serotonin is a neurotransmitter, or chemical that enables brain cells to communicate with each other. Low levels of serotonin are a possible cause of several depressive and anxiety disorders, including obsessive-compulsive disorder.
People suffering from obsessive-compulsive symptoms appear to have low serotonin levels, confusing brain messages. The brain may overreact to harmless thoughts that would otherwise be ignored, resulting in anxiety, doubt and invasive thoughts.
Brain scans support the case for serotonin imbalances as a cause for obsessive-compulsive disorder. The brains of people with obsessive-compulsive symptoms show different activity from people without the anxiety disorder. In addition, obsessive-compulsive disorder treatment often uses selective serotonin reuptake inhibitors (SSRIs) to control symptoms. SSRIs help maintain proper levels of serotonin in the brain.
Biological Obsessive-Compulsive Disorder Causes
Abnormalities in brain structure may cause obsessive-compulsive symptoms. People with OCD often have abnormalities in three particular areas of the brain:
- The basal ganglia, which influence routine behaviors;
- The cingulum, which help deliver behavioral and emotional messages; and
- The frontal lobes, which affect planning and organizing behaviors.
Behavioral Causes of Obsessive-Compulsive Symptoms
Behavioral habits have been suggested as a possible cause of obsessive-compulsive disorder. This theory holds that habits and behavioral responses learned over time contribute to and eventually cause obsessive-compulsive disorder.
PANDAS, Strep and OCD
PANDAS stands for Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections. PANDAS syndrome refers to the sudden worsening of obsessive-compulsive symptoms or tic disorders in children after a strep infection.
Strep infections are a common ailment, and very rarely result in PANDAS OCD symptoms. Some researchers point to PANDAS as a cause of pediatric obsessive-compulsive disorder, although PANDAS syndrome could simply be worsening preexisting but undiagnosed conditions. Children with PANDAS syndrome experience a sudden worsening of OCD symptoms after a strep infection. Symptoms gradually improve until the next strep infection, and then worsen again.
Sudden worsening and gradually improving symptoms are a hallmark of PANDAS syndrome – children with obsessive-compulsive disorder who do not have PANDAS syndrome tend to have consistent symptoms over time.
Whether or not PANDAS causes or worsens OCD symptoms, the possibility that the anxiety disorder can be affected by autoimmune responses could have profound implications on obsessive-compulsive disorder treatments.
Resources:
Healthy Place. (2009). Risk Factors and Causes of OCD.
Mayo Clinic. (2008). Obsessive-Compulsive Disorder (OCD): Causes.
National Institute of Mental Health. (2010). PANDAS.
Disclaimer:The information contained within this article is for informational purposes only, and is not intended to be a substitute in any way for care and treatment by a qualified health professional.
Michael McGrath - Michael McGrath began providing web content shortly after finishing his graduate degree in English at the University of Alberta. His broad ...
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