Dissociation is defined as mild to major disruptions in the way perceived environment, memory, sense of identity, or consciousness work together. It’s normal for most people to have experienced some degree of dissociation in the past. Extreme tiredness, for example, can make present experiences seem to occur in a dreamlike state, where the person feels removed from sense of self or surroundings. On the flipside, feeling any of these disruptions most of the time could suggest mental illness, experience of profound trauma, and/or specific dissociative disorders.
Two common types of dissociative expression are depersonalization and derealization. In depersonalization, the dreamlike state, as described above, prevails. People experiencing derealization doubt their surroundings and may have difficulty recognizing once familiar people and things. As stated, both of these conditions can occur transiently in healthy people, but become of greater concern if they worsen.
Difficulty seeing identity in a whole way can be dissociative. People may not know who they are, or they may establish new identities. In certain dissociative disorders, such as multiple personality disorder, shifts to several different identities can be exceptionally difficult. A core sense of consciousness doesn’t always exist about all identities present and this can lead to disorientation, losing time, or other features.
Another type of dissociation impacts ability to remember things. Amnesia may occur over short or long periods and is most often associated with occurrence of traumatic events. This is different from types of memory loss that are caused physically or organically. With dissociation, memories may still be accessible, especially through treatments like hypnosis.
There are several dissociative disorders and a number of other conditions in which dissociation may be noted. Dissociative identity disorder is also called multiple personality disorder. It usually features at least two wholly separate identities, which may or may not have consciousness of each other.
A couple of these disorders impact memory. Dissociative fugue occurs when a person forgets core identity and reestablishes himself somewhere else as a new personality. Dissociative amnesia is inability to recall many personal details about the self or history, and could include blocking out present memories so a continuous sense of time becomes disrupted.
People who feel as though they are living in a dream at all times may have a condition called depersonalization disorder. This is often characterized by other symptoms, like flat or minimal affect (emotion). Other mental health conditions have features of dissociation, too. Schizophrenics of certain types experience it, and it occurs in depression, anxiety, and post-traumatic stress disorder.
In most cases, dissociative conditions aren’t treated with medications. Instead, psychotherapy is frequently of most use, but exactly how it is best conducted is variable. There are also some theories that only a set population is likely to experience dissociation because they are somehow weaker in their integrated perceptions and consciousness. This hasn’t been proven, and the fact that most humans are subject to momentary disruptions in integration makes these theories less likely.