Obsessive Compulsive Disorder (OCD): Development (a Cognitive-Behavioural Model)

Check out my article on OCD Symptoms for Psychology Today.

This article…

I thought I’d write a little bit about how Obsessive Compulsive Disorder develops.

I hope people who don’t have OCD will be able to see that the mechanisms involved in OCD are very relatable.


I’ll use hand washing as an example. Excessive hand washing is a common type of OCD, but there are many other types. Handwashing is an example of a “compulsion” – something the person feels “compelled” to do repeatedly and in a very specific way.

1. For people with handwashing OCD, the disorder starts with the person making a conscious or UNCONSCIOUS connection between washing their hands and feeling better – calmer, less stressed.

Through evolutionary mechanisms, humans have developed so that cleaning, organizing, and ordering (as in putting things in a specific order) gives us a sense of greater well-being. This is because cleaning, organizing, and ordering were helpful to survival. To encourage us to do things that were helpful to survival, evolutionary processes have resulted in us being wired up so that doing those behaviours feels good.

2. The person washes their hands extra well and feels extra good, extra clean, and extra calm. They might develop a rule, like if they wash their hands while counting to 20 that feels adequately clean.

3. Then one of the times they wash their hands for a count of 20 they don’t feel clean at the end of it. This can happen either by chance or because the person is feeling extra stressed for some reason. Understandably, the person reasons that perhaps counting to 20 twice might do the trick, or perhaps only using a specific type of soap, or only using the bathroom at home.

4. The more times the person follows their rule in order to feel clean enough and calm, the harder it becomes to feel calm any other way.

5. Behaviour influences thoughts and feelings. Therefore, the more effort the person puts into getting their hands perfectly clean, the more anxious they become germs. Over time, they perceive not having clean hands as increasingly dangerous.

6. Usually at some point, the handwashing-related behaviour itself starts to become stressful. The person’s rituals about hand washing become “stress-generating”.

BUT doing more handwashing is, by this point, the person’s main way of feeling calmer and relieving stress, so a vicious cycle occurs.

7. The person might start to worry that they’re “losing their mind”. The additional stress of being worried they are going crazy creates EVEN MORE extra stress and anxiety. Which of course causes them to feel the need to do extra handwashing to soothe themselves.

8. The OCD behaviour and rules can often start to become objectively impairing e.g. the person will not use public bathrooms so can not go places. This often causes stress in relationships. The person’s friends and family might alternate between being understanding and accommodating, and being frustrated/angry. The person’s functioning in the workplace might be affected. All of this is stressful and causes the person to think increasingly negative thoughts about themselves. They might start to withdraw from people and/or activities.

9. When people with OCD start to develop complex rules for their behaviour, they might start to doubt whether they are accurately remembering whether they have completed their rules exactly. This generates more of a sense of “going crazy” and the feeling of needing to repeat behaviours to reduce anxiety, or to put additional rules in place so that they can remember to follow their procedure correctly.

10. Sometimes people develop rules that don’t seem logical. The person themselves might have a personal logic for why they use a particular rule or they may have stumbled on an association between doing something a particular way and feeling calmer, and their brain has created a strong connection.

11. People may be more vulnerable to developing Obsessive Compulsive Disorder during a time in their life when they are feeling high stress. During high stress, people are more likely to get pulled into compulsive behaviours that (even its only for a moment) help them alleviate their stress (think: overeating during high stress).

12. There are of course neuropsychological elements. Some individuals are more prone to feelings of anxiety than other individuals, and some people’s brains make very strong connections between compulsive behaviours and feeling better. These are “predisposition” factors. In children, OCD seems to sometimes be triggered by having had a recent strep throat infection.

13. Sometimes a specific environmental trigger is involved in onset. For example, someone might develop hand washing OCD after watching news coverage of bird flu or swine flu that urges people to wash their hands thoroughly. Sometimes no specific trigger can be identified.

How psychology PhDs Know This Stuff

Knowledge of specific types of mental health disorders comes from research studies.

In our training, psychology PhDs learn LOTS of different psychological models of 1. specific disorders, and 2. human psychology generally. What I’ve outlined above is one type of psychological model.

In trying to understand and propose a treatment plan for a specific individual, we piece together information from the specific individual with our knowledge of general and disorder-specific psychological mechanisms.