Obsessive-compulsive disorder, or OCD, is considered a type of anxiety disorder. According to psychologists Padmal de Silva and Stanley Rachman, people who experience obsessions suffer from unwanted and persistent thoughts. Compulsions are a related disorder, but they usually manifest as repetitive illogical behaviors such as washing hands for hours to remove germs. There are several theories on what causes OCD, including genetics, biochemical abnormalities, infection, depression and psychodynamics.
Genetics
According to social worker Bruce M. Hyman, Ph.D., and Cherry Pedrick, R.N., OCD runs in families. There does not appear to be a specific gene for the disorder. However, children appear to inherit brains with abnormal structures, biochemistry or processing abilities that predispose them to OCD when faced with childhood trauma or stress. According to Genetics-Health.com, researchers have only recently begun looking into hereditary causes of OCD. Researchers have found that relatives of children with OCD have a different type of gene that is involved with the flow of the amino acid glutamine. Other researchers have found gene mutations that may be related to abnormal serotonon levels and problems with how neuronal signals are sent.
Biochemical Abnormalities
Serotonin is a brain chemical called a neurotransmitter because it sends signals from one neuron to the next. When there is an inadequate amount of serotonin, a brain disorder such as OCD or depression may develop. According to BrainPhysics.com, the medication Prozac decreases symptoms of these disorders by increasing the supply of serotonin to the brain. Prozac and other medications in the class called selective serotonin reuptake inhibitors, or SSRIs, work by increasing the amount of serotonin that a nerve cell can receive so that the neurons spend more time in the serotonin before it is reabsorbed. On the other hand, de Silva and Rachman explain that although OCD symptoms may improve when given certain SSRI medications, that does not prove that the disorder was caused by a shortage of the chemical the medication bolsters. According to the authors on Anxietycare.org.uk, individuals with OCD may have structural abnormalities within the brain, the thalamus may not be processing sensory images normally and the basal ganglia may not filter sensory information---all contributing to illogical behaviors.
Infections
According to the Mayo Clinic, some children may develop OCD after contracting strep throat. They feel, however, that this theory is controversial and more studies are needed. Hyman and Pedrick report that contracting OCD after a strep infection is an example of a "pediatric autoimmune neuropsychiatric disorder," or PANDA. This may be because the strep infection can cause the body to attack nerve cells in the basal ganglia, which is a part of the brain very involved with motor control and learning.
Depression
According to the Anxiety Care website, people with depression sometimes develop OCD and individuals with OCD frequently develop depression. Perhaps the development of depression is partly due to the extremely debilitating symptoms of OCD. Medications such as Prozac may be used to treat symptoms of both anxiety and depression. However, without intervention to control the depression, it is very difficult to use treatment such as exposure or cognitive-behavioral therapy to hopefully change behaviors and thought patterns.
Theory/Speculation
Psychodynamic theory centers around Sigmund Freud's ideas about psychosexual development and the role of the unconscious. Psychotherapy based on this theory works to resolve conflicts. According to the Anxiety Care website, this theory states that OCD is caused by abnormal sexual or general development and conflict between the reasoning and impulsive parts of the mind. This theory does not currently appear to be popular within the medical community.
References
- Mayo Clinic: OCD: Causes
- Anxiety Care: Causes of OCD
- Genetics-Health: OCD and Genetics: Inheriting Obsessive-Compulsive Disorder
- BrainPhysics.com: How Prozac Works
- "Obsessive-Compulsive Disorder"; Padmal de Silva and Stanley Rachman; 1998
