Dissociative Identity Disorder (DID) is characterized by the presence of two or more separate personality states (dissociative identities), accompanied by gaps in personal agency and sense of self. This means that the person experiencing DID has the impression that certain thoughts, actions, and emotions don't belong to them, as they are sourced from another distinct identity.
You may see DID referred to as Multiple Personality Disorder or Split Personality Disorder, terms that most consider outdated and inaccurate. People with DID describe their experiences in a variety of ways. Some see themselves as multiple people or entities coexisting within one body, while others view themselves as a person composed of independent parts or sides. Dissociative identities may be called alters, parts, headmates, friends, voices, and more. Some people with DID use the term system to describe themselves collectively.
Each identity within a DID system has a unique experience of the world and distinct relationships with self, body, external individuals, and the environment. This comes with differences in thinking, feeling, moving, sensing, understanding, and interacting. Identities may be experienced covertly through intrusions of feelings, thoughts, and sensations that don’t feel like they belong to the individual. They can also be experienced overtly as different identities taking control of consciousness and functioning, also known as switching.
DID often involves experiences of amnesia, which can include the inability to recall traumatic events, the recent past, daily life details, or the activities of different alters. Amnesia is a diagnostic requirement according to the American Psychiatric Association (APA), but it is not included in the World Health Organization (WHO) definition of DID. Even without total amnesia, people with dissociative identities often feel a lack of ownership of particular memories, as if the remembered event happened to somebody else.
“Other specified” disorders exist in all diagnostic categories to describe clinically significant symptoms that do not meet the diagnostic criteria of a specific disorder. Other Specified Dissociative Disorder (OSDD) can refer to any mix of dissociative symptoms that are significant enough to warrant a diagnosis.
In the APA’s framework, somebody experiencing dissociative identities without amnesia may be diagnosed with OSDD. You may see subthreshold presentations of DID like this referred to as OSDD-1.
Depersonalization describes feeling detached from one’s self and body. It may be experienced as watching oneself in third person, or feeling numb physically and/or emotionally. Depersonalization may feel like “I am not real.”
Derealization describes feeling detached from other people, objects, and the world. It may cause the world to feel dreamlike, distant, foggy, or distorted. Derealization may feel like “the world is not real.”
Experiences of depersonalization and derealization can be upsetting and frightening. They can be a part of a variety of conditions, including PTSD, anxiety disorders, and of course, dissociative disorders. A diagnosis of Depersonalization-Derealization Disorder (DPDR) may be made when experiences of depersonalization and/or derealization are chronic, involuntary, and disruptive to an individual’s wellbeing.
Maladaptive Daydreaming is when the simple daydream is taken to a high spectrum where the person no longer knows how to stop and may spend hours or days at a time immersed in vivid storylines. They may lead a different life in their imagination, have different personal characteristics and meet anyone they wish, or go anywhere they want.
A person's relationship with their fantasies can be both positive and negative, in that they feel drawn to slip into the story, but may feel overwhelm at an inability to stop when needed. This becomes an interference to life's day-to-day activities and a source of fear that anyone would know and think negatively of them.
Unlike psychosis, a person who experiences Maladaptive Daydreaming knows the difference between fantasy and reality. They are aware that their stories exist only in imagination and this is not confused with actual happenings.
Post Traumatic Stress Disorder is the aftereffect of at least one traumatic experience. Examples of such events are the impact of a soldier following a war, or it can be a devastating car accident, an assault, being threatened or witnessing acts of violence.
Symptoms of PTSD include avoiding the memories or place of the trauma, or intrusive thoughts of the event, which may involve vivid images or reliving in recall, such as flashbacks. Changes in mood are common, such as angry outbursts or crying fits. Loss of recall of the trauma can occur. Following a traumatic event, a survivor may feel guilt and/or shame, as though they held responsibility.
Complex Post Traumatic Stress Disorder holds similarities to PTSD in that it is initiated by trauma. Key differences are that C-PTSD starts in childhood where the traumatic events are repeated, and often committed by a person in authority.