Obsessions are recurrent, intrusive, and unwanted thoughts, impulses, or images that cause significant anxiety. At first the obsession may be experienced as relatively benign. Over time, the person associates it with fear and disabling anxiety. Obsessions fall into the following common thematic categories:
- Fear of contamination with dirt, germs, or poisons
- Fear of having a serious illness
- Fear that one's actions hurt other people or cause bad things to happen
- Inability to discard useless items (hoarding)
- Inappropriate sexual and aggressive thoughts and images
- Need for symmetry, order, or exactness
People who fear contamination may obsess about shaking hands or touching public doorknobs. Those who obsess about the implications of their actions often fear they endanger others. They may feel they have left a door unlocked or hit someone while driving. Obsessions with symmetry and order may cause significant anxiety over furniture arrangement, eating habits, or clothing. Inappropriate sexual impulses and pornographic images, often of an aggressive nature, can dominate a person's mind. Obsessions of aggression can also center on violent emotions, shouting out in public, or harming others. Hoarding useless items, like outdated catalogs or clothing, is common in OCD and may coincide with an obsession over order.
People suffering from OCD realize that they create their obsessions. They feel that the content of their obsessions is out of their control, inappropriate, not indicative of their character, and something they wouldn't normally think or communicate to others. Thus, their anxiety is intensified not only by recurrent obsessions, but also by the strangeness of the obsessions.