Overcoming OCD
Information for College Students

What Causes OCD?

What Doesn’t Cause OCD

Everyone’s brain churns out random and strange thoughts.  Most people simply dismiss them and move on, but they get “stuck” in the brains of people with OCD.  These random thoughts are like the brain’s junk mail. Most people have a spam filter and can simply ignore junk mail that comes their way.  But having OCD is like having a spam filter that has stopped working—the junk mail just keeps coming and you cannot make it stop. Soon, the junk mail seriously outnumbers the wanted mail, and you become overwhelmed.  So why does the brain of individuals with OCD work this way?  In other words, what causes OCD?  You don’t really need to know what causes OCD to be able to get treatment and get relief.  But since you asked:

Using a specific type of brain scan (a positron emission tomography or PET), scientists have shown that functioning in some areas of the brain is different between people who have OCD and those who don’t. 

Research shows that the disorder may involve communication errors that take place between the orbitofrontal cortex (front part of the brain), the striatum, and the thalamus (deeper parts of the brain).  Abnormalities in the serotonin and other neurotransmitter systems—chemicals that send messages between brain cells – also are involved in the disorder.

A study funded by the National Institutes of Health examined DNA, and the results suggest that OCD and certain related psychiatric disorders may be associated with an uncommon mutation of the human serotonin transporter gene (hSERT).  People with severe OCD symptoms may have a second variation in the same gene.  Other research points to a possible genetic component—about 25% of OCD sufferers have an immediate family member with the disorder.

There are a number of other factors that may come into play with OCD.  Learning theorists, for example, suggest that behavioral conditioning may contribute to the development and maintenance of obsessions and compulsions.  More specifically, they think that compulsions are actually learned responses that help someone reduce or prevent anxiety or discomfort associated with obsessions or urges.  A person who has an intrusive obsession about germs, for example, may do hand washing rituals to reduce the anxiety caused by the obsession.  Because this washing ritual temporarily reduces the anxiety, the chances are greater that the person will wash his or her hands when a contamination fear occurs in the future.  So the compulsive behavior not only continues but actually becomes excessive.

Many cognitive theorists believe that people with OCD have faulty or dysfunctional beliefs, and that it’s how they misinterpret their intrusive thoughts that leads to obsessions and compulsions.  According to this theory, everyone has intrusive thoughts. But people with OCD misinterpret their thoughts; they believe their thoughts are very important, have some personal significance, tell something about their character, or will have catastrophic consequences.  When a person misinterprets these thoughts over and over again, obsessions develop.  Because the obsessions are so upsetting, the person does rituals to try to resist, block, or neutralize them.

The Obsessive-Compulsive Cognitions Working Group is an international group of researchers who believe that OCD is the result of misinterpretations of intrusive thoughts.  They have identified six different types of faulty or dysfunctional beliefs associated with OCD:

1.  Inflated responsibility: a belief that one has the ability to cause and/or is responsible for preventing negative outcomes;

2.  Overimportance of thoughts (also known as thought-action fusion): the belief that having a bad thought can influence the probability of the occurrence of a negative event or that having a bad thought (e.g., about doing something) is morally equivalent to actually doing it;

3.  Control of thoughts: A belief that it is both essential and possible to have total control over one’s own thoughts;

4.  Overestimation of threat: a belief that negative events are very probable and that they will be particularly bad;

5.  Perfectionism: a belief that one cannot make mistakes and that imperfection is unacceptable; and

6.  Intolerance for uncertainty: a belief that it is essential and possible to know, without a doubt, that negative events won’t happen.

Other factors that may come into play with OCD have to do with the environment.  For example, traumatic brain injuries have been associated with the onset of OCD, which provides further evidence of a connection between brain function impairment and OCD.  And some children begin to exhibit symptoms after a severe infection such as strep throat.  Studies suggest the infection doesn’t actually cause OCD, but triggers symptoms in children who are genetically predisposed to the disorder.

Stress and parenting styles are environmental factors that have been blamed for causing OCD.  But no research has ever shown that stress or the way a person interacted with his or her parents during childhood causes OCD.  Stress can, however, be a factor in triggering OCD in someone who is predisposed to it, and OCD symptoms can worsen in times of severe stress.

In sum, although the definite cause or causes of OCD have not yet been identified, research continually produces new evidence that hopefully will lead to more answers.  It is likely, however, that an interaction between various risk factors over time is responsible for the onset and maintenance of OCD.

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