Dissociative and Somatoform Disorders 345
Criticisms of the DSM-IV-TR Criteria
Significant problems plague the DSM-IV-TR diagnostic criteria for DID,
including the following (Piper & Merskey, 2004b):
- DSM-IV-TR does not defi ne “personality states” or “identities”; accord-
ingly, a normal emotional state that emerges episodically—such as periodic
angry outbursts—could be considered an “identity.” By leaving “personal-
ity states” and “identities” undefi ned, the criteria allow the possibility that
normal emotional fl uctuations could be considered pathological.- DSM-IV-TR does not indicate how clinicians can know when an alter has
“taken control” (Criterion B) (Fahy, 1988). With no guidelines for how to
make that judgment, there is apt to be little reliability in the diagnosis (see
Chapter 3 for a discussion of reliability and diagnosis).- DID—which is easy to role-play—can be difficult to distinguish from
malingering (Labott & Wallach, 2002; Stafford & Lynn, 2002). When
people can easily fake symptoms of a disorder, the validity of the disorder
as a diagnostic entity can be questioned (see Chapter 3 for a discussion of
validity and diagnosis).- DID can be difficult to distinguish from rapid cycling bipolar disorder
because both involve sudden changes in mood and demeanor. However,
appropriate treatments for bipolar disorder differ from those for DID,
which is why accurate diagnosis is important (Piper & Merskey, 2004b).Some of Anna O.’s dissociative experiences seem similar to those ofpatients with DID, such as her “naughty” states (for which she had amnesia)
and her feeling that she had two selves, a real one and an evil one, which
would “take control.”
Understanding Dissociative Identity Disorder
Research fi ndings on various factors associated with DID can be at odds with
each other, which only fuels the controversy over the validity of the diagno-
sis itself. As we shall see, much of the research on, and theorizing about,
factors that may contribute to DID hinge on the fact that many people with
this disorder report having been severely and chronically abused as children
(Lewis et al., 1997; Ross et al., 1991). As usual, we’ll begin by examining
neurological factors and then consider psychological and social factors.
Neurological Factors: Setting the Stage
Research that investigates possible neurological differences between alters
paints a mixed picture. On the one hand, the brain behaves differently when
an alter who is aware of relevant information listens to a story than when an
alter who is not aware of that information listens. As we note below, such differ-
ences in brain functioning could have something to do with early hormonal reac-
tions to stress, and such reactions might contribute to the disorder in part because
specifi c genes make certain people especially sensitive to stress. On the other hand,
although one alter may profess to be ignorant of events experienced by other alters,
rigorous testing often reveals that each alter does in fact have access to information
acquired by other alters.
Brain Systems One hallmark of DID is that memories acquired by one alter are not
directly accessible to other alters. However, in one study, the alters reported no mem-
ory for material that had been learned by other alters, but researchers nevertheless
found no difference in either recall or recognition between the amnesic alters and nor-
mal control participants (Huntjens et al., 2003). Moreover, other studies suggest that
although alters may report the subjective experience of amnesia, they do, in fact, have
access to memories of other alters (Huntjens et al., 2005, 2006, 2007; Kong, Allen, &
Glisky, 2008). Consistent with these findings, researchers have used changes in
Table 8.8 • Dissociative Identity Disorder
Facts at a GlancePrevalence- The prevalence rate for DID is diffi cult to specify,
although several surveys estimate it to be about 1%
( Johnson et al., 2006; Loewenstein, 1994). However,
some researchers view this fi gure as a signifi cant
overestimate (Rifkin et al., 1998).
Comorbidity- People with DID may also be diagnosed with a mood
disorder, a substance-related disorder, PTSD, or a
personality disorder (to be discussed in Chapter 13).
DID may be diffi cult to distinguish from schizophrenia
or bipolar disorder.
Onset- It can take years to make the diagnosis of DID from
the time that symptoms fi rst emerge. Because of this
long lag time and the rarity of the disorder, there is no
accurate information about the usual age of onset.
Course- DID is usually chronic.
Gender Differences- Although women are more likely than men to develop
DID, different studies have found varying gender
ratios, with women three to nine times as likely as
men to receive this diagnosis.
Cultural Differences- DID is observed only in some Western cultures and
was extremely uncommon before the 1976 televi-
sion movie Sybil, which was about a “true case” of
what was then called multiple personality disorder
(Kihlstrom, 2001; Lilienfeld et al., 1999).
Source: Unless otherwise noted, the source is American Psychiatric
Association, 2000.