In his new book "Breaking Free," former Dallas Cowboys star Herschel Walker claims that for much of his life, "he" was really "we." That's because he has Multiple Personality Disorder (MPD, or Dissociative Identity Disorder, as it was renamed in 1994 by the American Psychiatric Association).
The diagnosis is controversial, and some psychologists doubt it even exists. Many therapists don't see a single MPD case during their entire careers, while others find dozens of cases in their patient pool.
Those with the disease are said to have at least one (in some cases dozens or hundreds) of different other personalities, called "alters," that can control the person's behavior and thoughts. Often the person will create different, specialized alters to deal with difficult situations.
Walker, for example, says he gave his alters names such as General, Daredevil, Enforcer, and Warrior, and that they "functioned as a kind of community supporting me.”
For such a rare disease, MPD is widely known. Its popularity is largely due to a best-selling 1973 book by Flora Schreiber which told the story of a young woman named Sybil who claimed to have sixteen different personalities inside her. That book was later turned into a film, and gave the idea of multiples and alters a high profile. Diagnoses soon skyrocketed, and for decades Sybil remained the symbol and definitive example of Multiple Personality Disorder.
In 1999, long-lost audio tapes provided a fascinating twist to Sybil's case, suggesting that in fact Sybil may not have had multiple personalities after all.
According to psychologist Dr. Robert Reiber of John Jay College in New York, the tapes indicate that the various personalities Sybil believed she had were unintentionally created during therapy by her psychiatrist, Dr. Cornelia Wilbur. The tapes, which had been placed in Reiber's desk in 1972 and forgotten, also show "Sybil" author Schreiber improperly ignoring a letter from Sybil to Wilbur in which she denied having multiple personalities. (Perhaps Schreiber realized that having Sybil say that the book wasn't true would hurt sales.)
Dr. Reiber is supported by Dr. Herbert Spiegel, a New York psychiatrist who treated Sybil when Wilbur was unavailable. Spiegel also believes that Sybil's personalities were iatrogenic, that is they arose from Wilbur's method of therapy.
Wilbur's treatment included giving names to each of Sybil's emotional states, much as Herschel Walker did. (This would be like saying that when you are feeling upset, you become "Mr. Cranky," and when you are feeling seductive you become "Brad Pitt.")
The original MPD diagnosis arose when Wilbur began to believe that the different names for Sybil's emotional states represented actual, distinct personalities within Sybil.
If the most famous victim of MPD probably did not have the disease she was internationally known for, where does that leave Walker and the tens of thousands of others who believe they have the disease? Whether MPD sufferers really have multiple personalities inside them — or their personalities are a product of therapy — the underlying mental illness is real, and sufferers deserve respect and treatment.
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Benjamin Radford is managing editor of the Skeptical Inquirer science magazine. His books and films can be found on his website.
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