Obsessions and Compulsions

What Is OCD?

OCD is a disorder that has a neurobiological basis.  People who have OCD are driven by obsessions (persistent, uncontrollable thoughts, impulses, or images that are intrusive, unwanted and disturbing) to perform compulsions (repetitive behaviors often called rituals) in an attempt to reduce anxiety, fear, worry, doubt and distress created by the obsessions.  These rituals may work, but the relief is only temporary.  Unfortunately, getting even momentary relief from obsessions makes it more likely that individuals will perform rituals whenever they experience obsessions.  Over time, the cycle continues, and OCD frequently gets worse.

Individuals who suffer from OCD may exhibit rituals that are easy to see (washing, checking), or they may perform mental compulsions (thought rituals, prayers, counting) that cannot be observed by others, including family, friends and co-workers.

In some cases, compulsions are shaped by the nature of the obsessions.  Compulsive washing, for example, is commonly performed in response to obsessive fears of germs.  Similarly, a fear of someone breaking into the house may lead to excessive checking of the doors, windows, and locks.

In other cases, the compulsive behavior is completely unrelated to the obsession. For example, a student may feel compelled to tap his desk multiple times to prevent harm from coming to his family while he is at school.

It’s important to note that people with OCD sometimes perform rituals in response to certain sensory stimuli rather than to a distinct obsession or fear. Visual, auditory or tactile sensations may trigger a need for something to look, sound, or feel “just right.” Upon seeing a checkerboard, for example, a person may experience a need to trace over each of the squares mentally in a symmetrical fashion.

In other cases, external triggers are absent, but the individual has an inner feeling and/or perception of discomfort that causes him or her to repeat a behavior until the feeling is relieved.  In other words, the behavior needs to be repeated until it feels “just right” or “complete.”  In yet other situations, repeating behavior is preceded by a need or urge rather than by obsessions or sensations.

Below are some examples of the more common OCD symptoms.

Fear of Contamination

Fear of Causing Harm to Others

OCD-Related Hoarding

Religious and Moral Fears

Extreme Need for Symmetry or Exactness

Need for Perfection

Sexuality Doubt

Postpartum OCD (PPOCD)

Other disorders may be present with OCD, each of which has distinct symptoms.  When one or more disorders co-exist with OCD, symptoms can be confusing, and the clinical definition of OCD may be blurred.  Learning about related disorders can help you better understand the symptoms you or someone you know is exhibiting.

Learn more about related disorders

Clinical definition of OCD

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