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What is obsessive compulsive disorder (OCD)?

Have you ever heard someone casually say that they are “so OCD?” If you have, it’s probably because OCD (obsessive compulsive disorder) is widely misunderstood in today’s society. Many people think if you like to clean your house a lot or have a quirky way of organizing your stuff, you have OCD – but that isn’t true. OCD is a change or disturbance in thought patterns that results in negative emotions and affects a person’s ability to behave normally. In particular, OCD is characterized by:
  • uncontrollable, intrusive thoughts, beliefs, and ideas
  • negative emotions like guilt and anxiety
  • repetitive and ritualistic behaviors or actions

How does your brain usually handle information?

Your brain is like a supercomputer – it constantly receives new data about your experiences and helps you understand it. To do this, different parts of your brain are programmed to handle different aspects of information processing. For example, one area of the brain might manage incoming sensory data, another might sort and prioritize your thoughts, and a third might convert your thoughts into emotional responses. They all interact with one another to control the flow of information throughout the brain. When all of the parts work together properly, you are able to quickly and accurately process information about the world around you.

What happens when things go wrong?

Sometimes the communication system between the different parts of the brain breaks down. When this happens, information isn’t processed correctly and the brain starts to make mistakes when it tries to sort new data or tell the body how to respond. OCD is linked to communication problems between parts of the brain that translate information into thoughts and actions, including the orbitofrontal cortex, caudate nucleus, cingulate gyrus, and the basal ganglia. When these parts of the brain malfunction, inappropriate information is passed through the system and the person becomes overwhelmed by their thoughts and actions.


Individuals who have been diagnosed with OCD experience two main symptoms- obsessions and compulsions.
Obsessions are intrusive and recurring thoughts, ideas, mental images, and beliefs that are often disturbing and cause significant emotional distress or dysfunction. As the person tries to work or go to school, their obsessive thoughts pop up and interfere with their ability to focus. Most of us can let go of an upsetting thought or belief that is bothering us, but a person with OCD is unable to control their obsessions. Some common obsessions include:
  • fear of contamination, germs, or dirt
  • fear of forgetting something (like turning off the stove)
  • fear of hurting yourself or others
  • unwanted thoughts about aggressive or sexual behaviors
  • excessive beliefs about the importance of perfection or symmetry
  • excessive beliefs about morality or religion
  • excessive superstitious beliefs (like the belief that stepping on a sidewalk crack will harm your mother)
Compulsions are behaviors or rituals that a person feels driven to do. Compulsions are often performed in an effort to reduce the anxiety and distress caused by obsessions. For example, an obsessive fear of germs often results in compulsive, repetitive hand washing. Compulsions can involve mental behaviors like repeating a word ten times in your head, or physical behaviors like tapping a desk ten times. They are usually irrational and have no connection or effect on the person’s problem or fears. Some common compulsions include:
  • counting, repeating words, or tapping
  • double-checking things like stove knobs, door locks, and light switches
  • cleaning or washing excessively
  • repeatedly contacting family and friends to confirm their safety and health
  • arranging items in a specific way or putting things in a certain order
  • following a specific routine or ritual
  • keeping items that should be thrown out, like old newspapers or empty containers of milk
Many people with OCD have good insight; they recognize that their obsessions and compulsions are unreasonable or unhelpful, but they still aren’t able to control their thoughts or behaviors. Obsessions and compulsions are especially distressing as they become more complex – some people develop rituals that take up hours of their day, every day. When this happens, the symptoms are considered severe because they have the power to affect most aspects of the person’s life and often interfere with relationships, work, and school.

Risk factors/causes

Most of the time OCD can’t be attributed to a single cause. Instead, they are the result of the interplay between several different risk factors.
  • Genetics: if you have a close family member with OCD, you are more likely to have it yourself.
  • Psychological factors: if you have symptoms of another mental illness, you are more likely to develop OCD. You are especially at risk if you have been diagnosed with an anxiety disorder or a mood disorder, like depression. Certain personality characteristics, like perfectionism, high sense of morality, and high sense of responsibility, are also associated with OCD.
  • Illnesses during childhood: in children, the body’s reaction to an infection with streptococcus (the bacteria that causes strep throat) can cause the sudden development of OCD.
  • Other illnesses or injuries: any time you have a physical illness or an injury to your brain, symptoms of OCD can be triggered. Traumatic brain injuries, certain viruses, and brain tumors have all been linked to the disorder.

How common is OCD?

OCD is one of the most common mental disorders and about 2% of US adults experience OCD at some point during their life. Of those, more than half endure symptoms that are extremely severe and cause significant problems. Men and women are diagnosed with OCD at equal rates, but men are more likely to experience symptoms during childhood. Approximately 25% of all cases of OCD are children under the age of 18, and 1/3 of adults with OCD developed the disorder at a young age.

Is OCD preventable?

Scientists and mental health professionals agree that the initial onset of OCD is not preventable, but that patients may be able to manage their symptoms once they have been diagnosed. To do this, people with OCD should identify any situations or events that could trigger their symptoms and keep a diary of their symptoms so they can immediately seek treatment if their symptoms get worse. They should also continue taking all their medications as prescribed. Sometimes patients stop taking their medications when their symptoms seem to improve or go away, but that is extremely dangerous - 20% of patients stop responding to medications that once worked for them because they stopped taking them as prescribed!

What are some treatments for OCD?

Treatments for OCD usually involve a combination of medication and psychotherapy, based on the specific needs and symptoms of the patient. These treatments work together to improve functioning and decrease symptom severity over time.


The medications used to treat OCD are called antidepressants. Antidepressants like selective serotonin reuptake inhibitors (SSRI’s) focus on fixing dysfunctional communication between the orbitofrontal cortex, caudate nucleus, cingulate gyrus, and basal ganglia. They do this by increasing the amount of a chemical messenger called serotonin in these parts of the brain, which improves information processing. Antidepressants can usually produce a 40-60% reduction in symptoms of OCD.


One of the most effective psychotherapies for OCD is cognitive behavioral therapy (CBT). CBT focuses on identifying and challenging maladaptive thoughts, emotions, beliefs, and behaviors, and then replacing them with more adaptive ones. CBT also exposes patients to the situations that they’re afraid of, and helps them to change their behavior. In doing so, CBT helps patients to cope with obsessions and resist compulsions, and usually produces a 60-80% reduction in symptoms of OCD.

Consider the following:

Scientists recently found that a gene that causes certain kidney disorders also causes symptoms of OCD. They believe the discovery could help them develop a urine test to identify babies and young children who may be at risk for developing OCD. Their test could eventually be a key part of early intervention and lead to better outcomes among children with a genetic connection to the disorder.

Want to join the conversation?

  • leaf yellow style avatar for user Ainslie Collins
    I'm actually so glad i found a great text about this. Being diagnosed myself (i didn't even realise my sister was the one that did) i hate it when friends and family go "sigh I'm so OCD" because most of the time its not used to even the right explanations :) thanks for the great explanation
    (30 votes)
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  • purple pi teal style avatar for user valvarez2015
    How come OCD is common in children?
    (5 votes)
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    • blobby green style avatar for user Tracy Byers
      All kids have worries and doubts. But kids with obsessive-compulsive disorder (OCD) often can't stop worrying, no matter how much they want to. And those worries frequently compel them to behave in certain ways over and over again.

      About OCD
      OCD is a type of anxiety disorder. Kids with OCD become preoccupied with whether something could be harmful, dangerous, wrong, or dirty — or with thoughts that bad stuff could happen.

      With OCD, upsetting or scary thoughts or images, called obsessions, pop into a person's mind and are hard to shake. Kids with OCD also might worry about things not being "in order" or "just right." They may worry about losing things, sometimes feeling the need to collect these items, even though they may seem useless to other people.

      Someone with OCD feels strong urges to do certain things repeatedly — called rituals or compulsions — in order to banish the scary thoughts, ward off something dreaded, or make extra sure that things are safe, clean, or right in some way.

      Children may have a difficult time explaining a reason for their rituals and say they do them "just because." But in general, by doing a ritual, someone with OCD is trying to relieve anxiety. They may want to feel absolutely certain that something bad won't happen or to feel "just right."
      (17 votes)
  • leafers seedling style avatar for user Kaan Tarhan
    Great article, do we know if there is a certain threshold a person can pass that makes their OCD irreversible? If it is highly curable why do we need an early intervention?
    (6 votes)
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  • purple pi purple style avatar for user Residuum
    The article states that up to twenty percent of patients stopped responding to medicine that once worked for them after they stopped taking it for awhile. Why would this be? Is it an immune response?
    (4 votes)
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  • aqualine ultimate style avatar for user elliehp
    I've noticed that SSRIs can be used for a lot of different things like anxiety, depression and bipolar disorder. Why is that exactly? What makes it so effective?
    (5 votes)
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    • aqualine ultimate style avatar for user Nikki
      SSRI's are selective serotonin re-uptake inhibitors. They keep the neurotransmitter, serotonin, from being drawn back into the synapse of a neuron. More of the neurotransmitter then circulates in the synaptic gap (space between the neurons), making it more availiabe. It helps with disorders where there is a lack of serotonin, such as depression.
      A note: it is more controversial to prescribe SSRI's for bipolar disorder, as it may cause more rapid cycling of the symptoms of mania and depression.
      (1 vote)
  • leafers ultimate style avatar for user Per Guterstam Christoffersson
    Thanks for a good read!
    A question regarding content: Is the orbitofrontal cortex really marked out correctly in the diagram "Normal information processing and OCD malfunctions in the brain"?
    Compare to for example:
    (4 votes)
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  • starky ultimate style avatar for user Zak
    What are the most common symptoms of OCD?
    (1 vote)
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    • starky ultimate style avatar for user Soph
      1. Obsessive thoughts that can border on psychotic, such as thinking you can get AIDS from touching a pole on the public bus, believing you have AIDS, and not being able to turn off the obsession on AIDS.
      2. Compulsive behaviors, such as excessive hand washing, checking things (like turning the stove off), and repetitive actions (must turn light on and off exactly 48 times).
      3. Major Depressive Disorder is comorbid with OCD, so symptoms of depression may be present.
      4. Hoarding
      5. Ritualistic behaviors, like a routine (must turn off lights 48 times before bed every day, then fall asleep at 12 a.m.)
      6. Unwanted thoughts (sexual, gory, etc.)
      7. Symptoms of another anxiety disorder, since anxiety disorders can be comorbid
      8. Motor tics in some people
      9. Body dysmorphia
      10. Self-harm (NSSI)
      (6 votes)
  • duskpin ultimate style avatar for user Cindy
    Can traumatic experiences or high amounts of stress over a long period of time cause OCD? This is a great article!
    (3 votes)
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    • duskpin seedling style avatar for user Sarah B.
      Yes, but usually someone has to have some sort of risk factor for this to happen. As said in the article, genetics or having other mental health issues can lead to the development of OCD. When someone has at least one of these risk factors, traumatic experiences and long periods of stress can trigger OCD-like thoughts, and eventually develop into OCD itself. Additionally, if the person already had OCD, stress and traumatic experiences will worsen the effects of it.
      (2 votes)
  • blobby green style avatar for user Sergio Chitlango
    how can i treat obsessive compulsive disorder without a person knowing, when counselling at church or workplace?
    (3 votes)
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  • female robot grace style avatar for user Ferrah Desiree Waddell
    Why do some diseases cause OCD?? And how?
    (3 votes)
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    • blobby green style avatar for user Tracy Byers
      In spite of a range of theories and considerable research, scientists so far have not been able to identify a definitive cause for a person developing Obsessive-Compulsive Disorder (OCD).

      However, whilst this may be the case, it is believed that OCD is likely to be the result of a combination of either neurobiological, genetic, behavioural, cognitive, or environmental factors that trigger the disorder in a specific individual at a particular point in time. Below is a summary of some of the suggested theories around the cause of OCD.
      (2 votes)