Obsessive-compulsive disorder, or OCD, is an anxiety-based disorder impacting over three million American adults in a given year, notes Family Doctor 23. OCD has no single cause, but the presence of this disorder increases the likelihood of having co-occurring anxiety disorders, such as panic attacks or bouts of depression. Treatment for OCD focuses on managing symptoms and correcting potential brain chemical imbalances, through the use of psychotherapy and medications.

Neurotransmitters of OCD

The brain comprises hundreds of neurotransmitters, which are chemical messengers communicating different functions to the body. For instance, neurotransmitters communicate the need to wash your hands after touching a dirty surface, and upon relaying this message, the body reacts by seeking a source for hand washing. A brain impacted by OCD relays the information differently due to an influx or reduction of specific neurotransmitters. The University of Utah notes that OCD is linked to decreased levels of the neurotransmitter serotonin and increased levels of dopamine. Overtime, a delicate interplay between these neurotransmitters increases the anxiety an individual with OCD experiences if the symptoms are not alleviated.

OCD Symptom Presentation

Obsessions refer to recurrent thoughts, ideas or images in the mind that persist until certain behaviors are completed. The behaviors are referred to as compulsions, or rituals. Individuals with OCD often experience specific types of obsessions and compulsions related to contamination, orderliness or harm of others, notes Family Doctor. Fear, worry or anxiety are the basis of the obsessive thoughts, which then prompt the individual to alleviate the increasing sense of anxiety through cleaning, arranging or repeating certain actions several times. The rationale of carrying out the rituals is linked to the individual believing that the feared thought abates as long as the compulsion is completed. Although those suffering from OCD recognize that the ritual does not necessarily make sense, they are nevertheless unable to stop the thoughts and behaviors.

Dopamine Pathway

Dopamine is the neurotransmitter linked to experiencing motivation, rewards and compulsions. When a pleasurable experience occurs, dopamine elevation in the brain mediates the sensation of pleasure. Essentially, OCD is a perpetuation of the reward sensation, by way of the completed compulsion lessening the anxiety brought on by the obsessive thoughts. Over time, the anxiety associated with obsessive thinking is stopped only by the pleasure of completing the compulsion, unless professional intervention breaks the cycle of obsession to compulsion. The Lundbeck Institute indicates that three major pathways of dopamine are involved in OCD 1. The brain regions of the substantia nigra, basal ganglia and caudate nucleus-putamen are overstimulated in those with OCD.

Relationship of OCD and Dopamine

Serotonin is the primary neurotransmitter associated with symptoms of OCD. Family Doctor notes that low levels of serotonin are linked to the repetitive thoughts, or obsessions, initiating the disorder. A 2004 study in the "American Journal of Psychiatry" indicates a positive correlation between increased dopamine activity and people with OCD.The study participants were treated with dopamine-based medications and treatment success was measured based on brain scan images. The results are significant for treating individuals with OCD with different forms of medication to target the dopamine receptors.

Dopaminergic Medication for OCD

Selective serotonin reuptake inhibitors, or SSRIs, are the first line of treatment for OCD. However, in lieu of research indicating that dopamine is also a significant chemical in the compulsive portion of OCD, additional medications are considered. The atypical antidepressant buproprion targets the dopamine pathway and in pairing this medication with an SSRI, fewer side effects occur, according to Brain Physics online.