Biology 202
2003 Second Web Paper
On Serendip

Obsessive-compulsive disorder, commonly known as OCD, is a type of anxiety disorder and was one of the three original neuroses as defined by Freud. It is characterized by "recurrent, persistent, unwanted, and unpleasant thoughts (obsessions) or repetitive, purposeful ritualistic behaviors that the person feels driven to perform (compulsions)." (1) The prime feature that differentiates OCD from other obsessive or compulsive disorders is that the sufferer understands the irrationality or excess of the obsessions and compulsions, but is unable to stop them. What differentiates people with OCD from other usually healthy people with milder forms of obsession and compulsion is the fact that the obsessions and compulsions serve to interfere with the person with OCD's life to the point where they are extremely distressed, the obsessions and compulsions take a large proportion of their time, and serve to interfere with the their routine, functioning on the job, normal social activities, and relationships with others. (1) (3)

Some of the typical compulsions that someone with OCD may exhibit include an uncontrollable urge to wash (especially the hands) or clean, to check doors repeatedly to make sure that they are locked, confirming that appliances are switched off multiple times, "to touch, to repeat, to count, to arrange, or to save." (1) Obsessions that one with OCD may display can include fixation on dirt and contamination, the fear that one may act upon destructive or violent urges, having an overdeveloped sense of responsibility for the welfare of others, objectionable religiously blasphemous or sexual disturbances, other socially unacceptable behavior, and an overbearing concern with the arrangement and symmetry of items. Obsessions may be present along with compulsions, or compulsions may be present singly; often times the compulsions are designed to reduce the anxiety associated with the obsession. (1) (2) (5)

The most common presentation of OCD is washing. The person is compelled to wash their hands many times a day and have constant thoughts of dirt, germs, and contamination. The person may spend up to several hours each day washing their hands or showering, and generally attempts to avoid items that they perceive as sources of contamination. (1)

A second subtype of the disorder is extreme doubt joined with compulsive checking; while some sufferers are preoccupied with symmetry, most people exhibiting this subtype are concerned with the safety of others. While checking something, such as the status of an appliance, would alleviate the doubt of a typical person, when a person with OCD checks something, their doubt is often heightened and often leads to even more checking. (1)

Those with OCD are usually quite aware of their irrational or extreme fears and behaviors, but are unable to control them. Because such behavior seen in OCD sufferers is often considered "crazy," otherwise normal people who suffer from OCD are often driven to hide their symptoms. Many are able to do so with remarkable success, as they are normal in all other aspects of their lives. The tendency to hide such behavior may be the reason of the recent epidemiological studies that show an incidence rate of around 2%, rather than the previously thought 0.05%. On the Zoloft informational site on OCD, they state that as many as one in fifty Americans, up to five million people, have OCD at some point in their lives. Around a third of the cases of OCD in the United States begin in adolescence, the second third beginning in young adulthood, and the final third beginning later on in life. While more boys will show evidence of OCD early in life than girls, men and women exhibit OCD in equal numbers in adulthood. (1) (5)

OCD is largely resistant to typical psychotherapy, which tries to get at the source of the conflict by going back to early childhood. However, OCD is more receptive to behavioral therapy, wherein the person with OCD is presented with the feared or triggering situation but is prevented from carrying out the accompanying compulsion. OCD is generally resistant to drugs used in the treatment of anxiety, depression, and psychosis. However, the symptoms generally ease with medications that influence the brain's serotoninergic system. (1)
Serotonin is a neurotransmitter that must be removed from a synapse by reuptake before it can be fired again. Clorimipramine, fluvoxamine, and fluoxetine are currently the only psychoactive drugs that block the uptake of serotonin, and all are effective in the treatment of OCD; this leads doctors to believe that the cause of OCD is closely related to the uptake of serotonin in the brain. It is thought that OCD may be closely related to tic disorders, such as Tourette's syndrome; it has been suggested that OCD and Tourette's share a common genetic basis. The examination of the brains of those with OCD with PET and MRI scans has shown that these people have abnormalities in the cortex and basal ganglia coupled with decreased caudate volume. More simply put, it is thought that in both OCD and tic disorders, there is a defect in a circuit that runs from the frontal lobe to the basal ganglia to the thalamus and back to the frontal lobe. Defects in this circuit may have a genetic basis or may arise from immunological factors, as suggested from the appearance of OCD and tic disorders after a Streptococcus infection. (1) (2)

Scientists have found that mice will exhibit OCD-like symptoms when their Hoxb8 gene is manipulated. In a study done at the University of Utah in Salt Lake City, one of the two Hoxb8 genes was manipulated in utero on mice from a line of inbred mice, as the mice would be identical to others from the line with only the exception of the manipulated gene. The mice with the manipulated gene were shown to groom themselves compulsively, often leading to bald patches of skin and open sores. Furthermore, the mice would also compulsively groom other mice in their cages just as forcefully. The scientists feel that feel that this could lead to some interesting findings about OCD, as well as for trichotillomania, a rare disorder where people pull out their hair, as the hox genes are largely similar in all vertebrates and could have a large influence on behavior. The Hoxb8 gene has also been shown to be active in areas that control animal grooming and the beginning of human OCD symptoms. This research helps to show that OCD most likely has a biological basis as well as a psychological basis, rather than only a psychological one. (4)

Both the Access Science articles and the information from the Zoloft website stressed the fact that the causes of OCD most likely have much to do with problems in the nervous system, there were some differences in how the information was presented. In the Access Science articles, there seemed to be a sense of distancing from those with OCD; the main article on OCD made sure to differentiate between people with "normal" obsessions and compulsions, and those people who have OCD. There was a clinical air to the articles, as if they were aimed at people who were researching OCD for a project or just general information, rather than being aimed at people who might possibly have or know someone with OCD. The Zoloft site, on the other hand, presented its information in a way that conveyed the sense that anyone could have OCD, and that those with OCD are not unusual for having it. The information was geared to those with OCD, their family members, and people who could possibly have it. (1) (2) (3) (5)

References

1) Obsessive-Compulsive Disorder, An article on obsessive-compulsive disorder by Joseph Zohar on McGraw-Hill's Access Science site, an online encyclopedia of science and technology.

2) Anxiety Disorders, A section of an article on anxiety disorders by Daniel S. Pine on McGraw-Hill's Access Science site, an online encyclopedia of science and technology.

3) Neurotic Disorders, An article on neurotic disorders by Marshal Mandelkern on McGraw-Hill's Access Science site, an online encyclopedia of science and technology.

4) Ancient Gene Takes Grooming in Hand, An article by Bruce Bower found through McGraw-Hill's Access Science site, an online encyclopedia of science and technology.

5) Understanding Obsessive Compulsive Disorder (OCD), An informational site about OCD, from the makers of Zoloft, which is used in the treatment of OCD and other anxiety disorders.


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