Scientists Are Beginning to Understand What Causes Multiple Personality Disorder -

[news reporter]

Scientists Are Beginning to Understand What Causes Multiple
Personality Disorder -
Despite the fact that dissociative identity disorder has been listed
in psychiatry bible Diagnostic and Statistical Manual of Mental
Disorders (currently DSM-IV) for years, the origins of the condition
are not well-understood. By Makini Brice July 02, 2012
Dissociative identity disorder (DID) - or multiple personality
disorder, as it is commonly known - affects one percent of the
population, roughly the same amount as schizophrenia. Often sufferers
from the condition have been misdiagnosed with schizophrenia and
bipolar disorder before receiving their DID diagnosis. DID is usually
characterized as a person who has with two or more personalities with
completely different viewpoints on their environments and themselves.
Some believe that those afflicted use DID as a means of coping with
extreme trauma, while others think that those affected simply have
overactive imaginations. Of those who believe in the overactive
imagination theory, scientists do not believe that DID is a genuine
mental disorder.
Researchers at King's College London sought to find a clearer picture
of the answer to that question. They studied 29 people, 11 had
dissociative identity disorder, 10 were people who were highly prone
to fantasy and 8 people were not very prone to fantasy, as a control.
Of those without DID, they were made to simulate the symptoms of
dissociative identity disorder. The researchers measured subjects'
brain activity, cardiovascular system, and their reactions.
They found that there were strong differences, both in regional blood
flow and in reactions, between the DID sufferers and the control
subjects. Researchers believe that indicates that DID sufferers do not
merely have overactive imaginations, and that the origins of their
ailment stem more likely from trauma....
http://www.medicaldaily.com/news/20120702/10574/dissociative-identity-disorder-multiple-personality-brain-mental-trauma.htm

Fact or Factitious? A Psychobiological Study of Authentic and
Simulated Dissociative Identity States (2012) A. A. T. Simone
Reinders, Antoon T. M. Willemsen, Herry P. J. Vos, Johan A. den Boer,
Ellert R. S. Nijenhuis PLoS ONE 7(6): e39279. doi:10.1371/journal.pone.
0039279
Abstract
Background
Dissociative identity disorder (DID) is a disputed psychiatric
disorder. Research findings and clinical observations suggest that DID
involves an authentic mental disorder related to factors such as
traumatization and disrupted attachment. A competing view indicates
that DID is due to fantasy proneness, suggestibility, suggestion, and
role-playing. Here we examine whether dissociative identity state-
dependent psychobiological features in DID can be induced in high or
low fantasy prone individuals by instructed and motivated role-
playing, and suggestion.
Methodology/Principal Findings
DID patients, high fantasy prone and low fantasy prone controls were
studied in two different types of identity states (neutral and trauma-
related) in an autobiographical memory script-driven (neutral or
trauma-related) imagery paradigm. The controls were instructed to
enact the two DID identity states. Twenty-nine subjects participated
in the study: 11 patients with DID, 10 high fantasy prone DID
simulating controls, and 8 low fantasy prone DID simulating controls.
Autonomic and subjective reactions were obtained. Differences in
psychophysiological and neural activation patterns were found between
the DID patients and both high and low fantasy prone controls. That
is, the identity states in DID were not convincingly enacted by DID
simulating controls. Thus, important differences regarding regional
cerebral bloodflow and psychophysiological responses for different
types of identity states in patients with DID were upheld after
controlling for DID simulation.
Conclusions/Significance
The findings are at odds with the idea that differences among
different types of dissociative identity states in DID can be
explained by high fantasy proneness, motivated role-enactment, and
suggestion. They indicate that DID does not have a sociocultural
(e.g., iatrogenic) origin.
For the first time, it is shown using brain imaging that neither high
nor low fantasy prone healthy women, who enacted two different types
of dissociative identity states, were able to substantially simulate
these identity states in psychobiological terms. These results do not
support the idea of a sociogenic origin for DID."
http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0039279