Understanding Alter Egos of Multiple Personality Disorder

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Is Multiple Personality Disorder Real?

Multiple Personality Disorder, (MPD) now termed Dissociative Identity Disorder (DID) is a rare condition and a controversial diagnosis. According to Piper and Merskey in The Persistence of Folly: A Critical Examination of Dissociative Identity Disorder. Part I. The Excesses of an Improbably Concept, prior to 1980 the Diagnosis of MPD was extremely rare. However, after 1980 the diagnosis increased significantly. Rationales used for this increase in diagnosis include that clinicians are more sophisticated in their ability to understand and diagnose MPD and that previously it was misdiagnosed frequently often being diagnosed as Borderline Personality Disorder. Additionally, Paul R. McHugh in Multiple Personality Disorder postulates that the condition is in fact created by therapists through the power of suggestion which is especially potent under hypnosis. Additionally, some clients may fabricate the diagnosis for personal gain such as attention or as a defense for insanity in court cases. I propose that all contentions are arguably accurate. MPD is in fact real but rare and is over diagnosed and potentially created by well meaning therapist.

Ego States

Understanding the development of alter egos of Multiple Personality Disorder is one of the most intriguing aspects of MPD. While ego states exist within all of us, someone with Multiple Personality Disorder develops extreme, dissociative alter ego states. An Ego state can be simply understood as the “hats” we wear for each area of our lives. For example, a person will behave differently when playing with his or her children versus when he or she is at work. We develop these ego states through processes known as differentiation and integration. When we integrate, we put things together into understandable units or labels. For example we learn that rabbits and dogs are all animals. We differentiate specific animals from each other such as learning that some dogs are nice and some are mean. Accordingly, our behaviors change based on these understandings. For example, we act one way around a nice dog and another around a mean one. As children, we behave differently on the play ground than in the classroom, or at grandmas than we do at our own home. We adapt our behaviors to our environments and circumstances based on internalized views of self and others. These ego states are adaptive and normal. The boundaries are flexible and “everyone knows what everyone is doing” because it is one individual changing roles as he or she enters into different situations.

When these boundaries are rigid and impermeable and typically a reaction to trauma, you may develop Multiple Personality Disorder. Everyone does not know what everyone else is doing. The person has split off aspects of themselves into alternate ego or personality states that are not aware of each other. These alter egos are distinctly different from one another including having different mannerisms, eye sight, and tone of voice, gender and memories of the person’s life.

Alter Egos of Multiple Personality Disorder

When trying to understand the development of alter egos of Multiple Personality Disorder, it is believed that these dissociated ego states are developed as a defense against trauma. The person “walls off” parts of themselves and their lives into separate personalities in their own minds that they are not even aware exist. Often someone with MPD may develop a persecutor personality who may cause significant problems in their lives. This person may be violent, engage in criminal activity or other self destructive behaviors such as self injury or suicidal gestures. The persecutor personality often holds the anger and extreme hurt from the abuse experienced as a child and in its own maladaptive way is trying to protect the individual from further hurt. They likely have memories of the abuse of which the host personality is unaware. This personality state typically emerges when the person is under extreme stress or perceived danger that the persecutor feels the host personality is too weak to handle.

Furthermore, those who suffer from MPD often possess a child ego state. You may think about it in the sense as if this child ego state is stuck in the abuse and has never grown up. Different circumstances in one’s life will trigger these personality states similarly to how our own ego states can be triggered. For example, someone’s behavior towards us may remind us of how we were treated as a child and we may find ourselves acting similarly to how we acted at that time in our lives. However, we are aware of this whereas this trigger in a person with MPD may result in a total switch to a new personality with the host personality having no awareness of this switch. What happens during this time will not be remembered by the host personality. How confusing and potentially devastating this can be to someone.


Bowman, Elizabeth S. MD, Coons, Philip M MD, The Differential Diagnosis of Epilepsy, Pseudoseizures, dissociative identity Disorder and Dissociative Disorder Not Otherwise Specified. Bulletin of the Menniger Clinic, 2000

Piper, August MD,, Merskey, Harold DM, The Persistence of Folly: A Critical Examination of Dissociative Identity Disorder Part I. The Excesses of an Improbable Concept. The Canadian Journal of Psychiatry, September 2004.

Gillig, Paulette Marie, MD PhD, Dissociative Identity Disorder: A Controversial Diagnosis. Pubmed, Psychiatry(Edgmont) 2009 March, 6(3):24-29

McHugh, Paul R. MD, Multiple Personality Disorder (Dissociative Identity Disorder). psycom.net

Watkins, Helen H. Ego-State Therapy: An Overview. American Journal of Clinical Hypnosis Volume 35, Number 4, April 1993 Pages 232 - 240

This post is part of the series: Multiple Personality Disorder

Multiple Personality Disorder is explained with an in depth look at what dissociation is and how or why it may occur. Later, alter egos and ego states will be clearly explained as well as how these alter personalities develop and their role in the individual’s life.

  1. Understanding Alter Egos of Multiple Personality Disorders