Multiple Personality Disorder

Some psychologists and psychiatrists believe that instances of demon possession recorded over the centuries may have really been MPD, but the first complete account of a patient with multiple personality disorder was written in 1865. Four years later, French neurologist Pierre Janet discovered that a system of ideas split off from the main personality when he hypnotized his female patients. Soon afterward, William James, the father of American psychology, uncovered a similar phenomenon and termed the condition disassociation. In 1886, American author Robert Louis Stevenson popularized the disorder in his novel The Strange Case of Dr. Jekyll and Mr. Hyde. Although this work of fiction captured popular imagination, the concept of multiple personalities was rejected by Sigmund Freud and later by the behaviorists. The mental health community believed the disorder was extremely rare if it existed at all.

Despite well-known movies such as The Three Faces of Eve and Sibyl, which recounted the life stories of women with MPD, by the beginning of the last decade only about 200 cases had been documented in world psychiatric literature. Finally in 1980 the American Psychiatric Association officially recognized multiple personality disorder as a genuine emotional illness.

Today, MPD is a relatively popular diagnosis with 20,000 cases recorded between 1980 and 1990. Researchers currently believe that from 0.01-10% of the general population has this mental illness. MPD occurs from 3-9 times more frequently in women than in men. Some researchers believe that because men with MPD tend to act more violently than women, they are jailed rather than hospitalized and never diagnosed. Female MPD patients often have more identities than men, averaging 15 as opposed to males, who average eight.

Because of the high number of MPD cases being diagnosed in the United States today, some professionals speculate that the diagnosis is culture-specific and caused by some unique characteristic of American society such as the high incidence of child abuse. Other experts, while not denying that MPD exists, believe that the high rate of MPD has been inflated by recent media attention focusing on criminal trials in which defendants use multiple personality disorder for the insanity defense. They also think that overly eager therapists may unknowingly encourage highly-suggestible patients to display symptoms during hypnosis. Experts who counter these assertions state that normal people cannot be taught, even under hypnosis, to imitate the measurable physical changes shown by those diagnosed with multiple personality disorder. They claim that in the past the condition was underreported, a situation now being corrected by a heightened awareness of the disease and its symptoms.