The Phenomenon of Dissociation

Have you ever seen a movie in which the main character wakes up in a strange hotel room, dressed weirdly, with no idea how she got there, and no relationship to the name she gave hotel staff upon check-in? Such drama is the stuff of Hollywood depictions of dissociative disorders.

Dissociative identity disorder (DID), known as multiple personality disorder (MPD) until renamed in the DSM-IV (American Psychiatric Association, 1994), has attracted a lot of attention in the mental health field due to the unusual features of its symptomatology and the various controversies surrounding it. While MPD did not appear as an official disorder until the publication of the DSM -III in 1980 (Coons, 1980), the growing recognition of psychiatric conditions resulting from traumatic influences has come to be seen as a significant mental health issue. Until recently, DID was considered a rare and mysterious psychiatric disorder.

However, DID and other dissociative disorders (DD) are now understood to be fairly common effects of severe and extreme trauma in early childhood when repeated physical, sexual and emotional abuse are part of the individual’s history. In fact, the placement of dissociative disorders in the DSM-5 is next to (but not part of) the chapter on trauma and stressor-related disorders, reflecting the close relationship between these diagnostic classes (APA, 2013).

There are various dissociative disorders, all of which feature some form of dissociation. But what, exactly, is the phenomenon of dissociating about?

The phenomenon of dissociation

“Dissociation” describes a state in which the integrated functioning of a person’s identity, including consciousness, memory, and awareness of surroundings, is disrupted or eliminated. Specifically, dissociation is a mechanism or specific mental strategy that allows the mind to separate certain memories or thoughts from normal consciousness. These memories are not erased, but are buried or compartmentalised and may resurface or come out of the compartment at a later time. Dissociation is often explained as being a type of self-hypnosis that takes on the form of a hypnotic trance involving a temporarily altered state of consciousness. Occurring along a continuum, dissociation is often a normal part of human experience in milder forms, while the more extreme forms can become markedly debilitating.

How did I get here? Everyday dissociation

An example of everyday, mild dissociation is when a person is driving for a long period of time – say, on the motorway – and takes several turns and exits without remembering any of them. When prompted the person may find it almost impossible to recollect driving through those specific areas at all, even though they know that they did, and know that they did so without running off the road or causing an accident. In this instance, the mind continued to focus on driving and all that was required to keep safe, but it did so at an automated, unconscious level in which the driving activity was held in the background (or the unconscious part) of the mind while thoughts or daydreams predominated in the foreground: the overtly conscious part of the mind. Memory finds it easier to recollect what has been attended to in the foreground rather than what was occurring in the background of the mind. Hence, the daydreaming is remembered more readily than the road travelled. The point at which conscious attention switches from the driving to the day dream – even though an unconscious focus on the driving is maintained – is the act of moving to a mild dissociated state while driving.

Pathological dissociation

In more severe forms of dissociation, an individual begins to experience a lack of awareness of important aspects of his or her own identity (Phelps, 2000), so rather than simply slipping out of conscious awareness when driving down the motorway, certain aspects of the person’s identity (that is, aspects such as how s/he would normally think, feel and behave) slip into the background and are forgotten. A very important factor to remember in the process of dissociation is that while the specific element of focus (e.g., driving a car or thinking, feeling and behaving in a certain way) may end up receding into the background of consciousness and being forgotten, it can still function or operate as if in full awareness. So while a person in a mild dissociative state can still drive proficiently down the motorway while daydreaming and not being fully aware that he or she is d riving, so too a person in a more severe dissociative state can end up functioning in clear expression of thought, feeling and behaviour without being fully aware of doing it.

Contextualising the full scope of how dissociation can manifest, Braun (1988) suggests that the dissociative spectrum can extend from normal dissociation to a poly-fragmented dissociative identity disorder (DID). Dissociative identity disorder is at the extreme end of dissociative spectrum disorders and is a disturbance of identity in which two or more separate and distinct personality states, or identities, control the individual’s behaviour at different times (Loewenstein, 2005) and alternate between the foreground and background of conscious awareness.

The phrase “dissociative identity disorder” replaced “multiple personality disorder” because the new name emphasises the disruption of a person’s identity that characterises the disorder, while the term dissociation draws attention to the actual mental process taking place. When under the control of one identity, (i.e. when those aspects of self are in the conscious foreground), the person is usually unable to remember some of the events that occurred while other personalities were in control. The different identities, referred to as alters, can develop so independently of one another that they exhibit differences in speech, mannerisms, attitudes, thoughts, and gender orientation. The alters may differ in “physical” properties such as allergies, right-or-left handedness, or even the need for eye glass prescriptions. The differences are d istinct and can often be quite striking to the observer (Haddock, 2001).

Dissociation is typically used to escape stressful or harmful situations by creating another place for the mind to go (such as when a person daydreams) while leaving some aspect of the self in the stressful or harmful environment to automatically function in it (Haddock, 2001). Thus the aetiology of DID is predominantly trauma-based. Symptoms develop as a result of dissociating from extreme traumatic events and then continue through ongoing habitual dissociation in survivor attempts to distance themselves from the traumatic memories (Kluft, 1996). Dissociation is therefore most likely to occur at the exact time a traumatic event is being experienced and when the horrific emotional distress that accompanies it is coupled with a strong sense of powerlessness to stop it or escape from it. Finding a place for the mind – a place for the self to hide – while being subjec ted to a traumatic event, is the only way the individual sees to cope (Holstrom, 1988).

Logically then, DID can happen to victims of any form of abuse. When the abuse is severe, dissociation or “splitting” might be the only means of escape. For example, when a person is completely overpowered and any form of resistance could lead to their death, splitting allows the individual to hold one aspect of themselves in the trauma to deal with it – albeit in an automated, emotionally detached way – while taking other aspects of the self away from the trauma and into the mind: into the daydream.

Subjective and objective reality: the development of alters

Those who have been subjected to trauma on an ongoing basis often report that the inside world of the ‘daydream’ feels more real than the objective events that occur outside, and that they prefer the world of the daydream to the objective reality of whatever is going on around them. Some client accounts of being in the daydream have been described as feeling like being inside one world (the daydream world that is very real to them) while looking out to a world that they don’t know (the objective reality of real-life experience).

If this process of ‘moving into the world of the mind’s dream’ occurs on a regular basis as a primary way of dealing with ongoing trauma, it can eventually bring on the development of other personalities: the alters that are created to help the individual survive the abuse. Alters constellate when dissociated individuals only allow certain aspects of their personality to the foreground at certain times (e.g., while being subjected to horrific abuse) while keeping other aspects of their personality in the daydream world. The more this occurs, the more the individual will switch between alternate states of consciousness in order to alter which parts of their personality stay in objective reality and which parts go for safety by moving back into the daydream.

As the dissociating individual continues with ever-greater frequency and intensity to alternate states of consciousness, the distinct qualities of each alter are reinforced. Consequently over time, rather than developing an integrated mindfulness of a whole, stable self, the dissociating person develops a personality that is split and in a continual state of flux, moving from one aspect of personality to another and from the objective reality of the tangible world to the subjective reality of the daydream world. Some parts of the personality may never enter the daydream while other parts of the personality may never enter the objective world.

The alters become increasingly distinct from one another, with very different characteristics, cognitive processes, memory, and physiology. They are experienced by the client as being different people. In many instances the altered states are not aware that they share one body (Kunzman, 1990) while in other instances they may consider themselves as separate people while accepting they share the same body.

Prevalence and Incidence

While the true prevalence of the disorder is hard to determine due to its undetectable nature, DID has been found in a wide range of cultures throughout the world. For example, while one study reported that 4% of Turkish outpatients could qualify for a diagnosis of DID (Levy & Swanson, 2008), it is generally reported in less than 1% of the population, with it being three to nine times more prevalent in adult women than adult men (Levy & Swanson, 2008). It has also been found that 15% of clients experiencing substance dependency may also be dealing with DID (Ross, 1997 cited in Levy & Swanson, 2008).

There has been a sharp rise in reported cases of dissociative identity disorder in recent years and this finding has been subject to different interpretations. One possibility is that greater awareness of the disorder among mental health professionals has resulted in easier identification of cases that were previously undiagnosed. Conversely, the syndrome may be over-diagnosed due to being induced in individuals who are highly suggestible.

This article was adapted from the Mental Health Academy CPD course “Dissociative Identity Disorder” This course offers an introduction to dissociative identity disorder which includes an overview of its diagnostic boundaries, aetiology, prevalence, and treatment. The differentiation between borderline personality disorder and dissociative identity disorder is also covered as a consequence of the similarities in aetiology, symptomatology and at times, co-morbidity, of the two disorders.


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