According to the DSM-5, this disorder is a type of dissociative disorder. Unlike other dissociative disorders, it usually does not cause memory problems. The main symptoms are repeated episodes of:


•          Depersonalization – feeling like your own mind or body is unreal, strange, or separate from you.

•          Derealization – feeling like the outside world around you is unreal or strange.

For example, some people feel like they are watching themselves from outside their body, or as if their mind is floating above them.

The feeling of unreality affects senses and behavior.

For example, they might:

•          Feel touch or smell differently,

•          Experience time and space in strange ways,

•          Feel like they are not controlling their speech or actions.

Derealization focuses more on the outside world. People may feel like objects are changing shape or size, or that others seem distant, robotic, or lifeless. For example, one graduate student reported seeing people as robots, perceiving his girlfriend strangely, and even questioning if his therapist was really alive. Having short experiences of depersonalization or derealization does not mean someone has the disorder. These temporary feelings are actually quite common.

•          About one-third of people say they have, at times, felt like they were watching themselves in a movie.

•          One-third of people facing life-threatening situations also report such feelings.

•          People may also feel this way after meditation, traveling to new places, or during childhood while developing self-awareness.

In most of these cases, the episode is temporary. People usually manage the strange feelings and continue living normally until the sensations fade away.

 

In contrast,

Depersonalization-Derealization Disorder is different:

•          The symptoms are persistent or keep coming back.

•          They cause serious distress.

•          It usually starts suddenly, most often in teens or young adults, and rarely after age 40.

•          People who have gone through trauma or life-threatening events are more vulnerable.

The disorder often lasts a long time. Symptoms may disappear for a while but return, especially during stressful times. So far, only a few theories exist to explain why this disorder happens.