CHAPTER 15

Dissociative Disorders

José R. Maldonado, M.D., FARM., F.A.C.F.E.

David Spiegel, M.D.

The dissociative disorders involve a disturbance in the integrated organization of consciousness, memory, identity, emotion, perception, body representation, motor control, and behavior. Events normally experienced on a smooth continuum are isolated from the other mental processes with which they would ordinarily be associated. This discontinuity results in a variety of dissociative disorders depending on the primary cognitive process affected. When memories are poorly integrated, the resulting disorder is dissociative amnesia. If the amnesia also includes aimless wandering, the specifier "with dissociative fugue" is used. Fragmentation of identity results in dissociative identity disorder (DID). Disordered perception yields depersonalization/derealization disorder and, in conjunction with the symptoms of posttraumatic stress disorder (PTSD), produces its dissociative subtype. Dissociation of aspects of consciousness is also involved in acute stress disorder.

Dissociative disorders represent more a disturbance in the organization or structure of mental contents than a disturbance in the contents themselves. Memories in dissociative amnesia and/or identity during fugue states (as part of dissociative amnesia) are not so much distorted or bizarre as they are segregated from one another, impairing retrieval. The aspects of the self that are fragmented in DID are two-dimensional aspects of an overall personality structure. The problem is the failure of integration or the decontextualization of information, rather than the contents of the fragments. In summary, all types of dissociative disorders have in common a lack of immediate access to the entire personality structure or mental content in one form or another. The dissociative disorders have a long history in classical psychopathology but until recently have been largely ignored. Nonetheless, the phenomena are sufficiently persistent and interesting that they have elicited growing attention from both professionals and the public. The dissociative disorders remain an area of psychopathology for which the best treatment is psychotherapy (Maldonado et al. 2002). As mental disorders, they have much to teach us about the way humans adapt to traumatic stress and about information processing in the brain.

Development of the Concept

Jean-Martin Charcot (1890), the well-known French neurologist, became interested in the dissociative symptoms experienced by some of his patients who had unusual neurological symptoms. He discovered that hypnosis could reproduce and reverse some of the deficits manifested by his patients. Charcot believed that even a normal process such as hypnosis, which could be used to access dissociated mental contents, was itself evidence of pathology—"un état nerveux artificiel ou expérimental" (i.e., an artificial or experimental nervous state). He thought, for example, that once patients were cured of hysteria, they would no longer be hypnotizable. This is now known not to be the case because many "normal" individuals are highly hypnotizable (Spiegel and Spiegel 2004).

Nevertheless, the French physician and psychologist Pierre Janet (1920) is credited with the initial description of dissociation as a disorder, a désagrégation mentale. The term désagrégation carries with it a slightly different nuance than does the English translation—dissociation—because the former implies a separation of certain mental contents from their general tendency to aggregate or be processed together. Janet (1920) described hysteria as "a malady of the personal synthesis" (p. 332). Janet was probably the first to study psychological trauma as a principal cause of dissociation.

The dissociative disorders might have been studied more intensively during the twentieth century had not Janet's and Charcot's work been so thoroughly eclipsed by the psychoanalytic approach pioneered by Sigmund Freud. Freud learned the use of hypnotic techniques from Charcot and applied them in the treatment of some of his first cases. In his early writings with Breuer, Freud began an exploration of dissociative phenomena, similar to those that Janet had described earlier. Cases in the Studies on Hysteria (Breuer and Freud 1955), such as that of Anna O., clearly involved dissociative phenomena. Indeed, Anna O. had many symptoms suggestive of DID. However, Breuer and Freud reformulated the role of the capacity to dissociate through the concept of hypnoid states, rather than the mechanism of dissociation. Indeed, they thought that dissociative symptoms should be attributed to the capacity to enter these hypnoid states rather than the reverse (Breuer and Freud 1955). However, in an effort to develop a more general theory of human psychopathology, Freud went on to study other kinds of patients, such as those with "obsessive compulsive neurosis" (i.e., obsessive-compulsive disorder) and schizophrenia. This shift in the patient population studied may well account for much of Freud's waning interest in dissociation as a defense and his increasing interest in repression as a more general model for motivated forgetting in unconscious processes. Discussion of dissociation and its relation to trauma all but disappeared after Janet. However, during World War II and the postwar period, some psychiatrists began to pay attention to two emerging phenomena: 1) a high incidence of "traumatic neurosis" among combatants and 2) dissociative symptoms such as fugue and amnesia observed among exinmates of concentration camps.

As a general model for keeping information out of conscious awareness, repression differs from dissociation in several important ways (Table 15-1). There has been debate about whether dissociation is a subtype of repression or vice versa. Such a dispute is probably not resolvable, but what has become clear in recent years is that given the complexity of human information processing, the accomplishment of a sense of mental unity is an achievement, not a given (Spiegel 1986). What is remarkable is not that dissociative disorders occur but rather that they do not occur more often, given the fact that information processing comprises a variety of reasonably autonomous subsystems involving perception, memory storage and retrieval, intention, and action.

^aThe organizational structure of mental contents in dissociation is considered to be horizontal, with subunits of information divided from one another but equally available to consciousness (Hilgard 1977). Repressed information, on the other hand, is presumed to be stored in an archaeological manner, at various depths, and therefore different components are not equally accessible (Freud 1923/1961).

^bSubunits of information are presumed to be divided by amnesic barriers in dissociation, whereas dynamic conflict, or motivated forgetting, is the mechanism underlying repression.

^cThe information kept out of awareness in dissociation is often for a discrete and sharply delimited time, usually for a traumatic experience, whereas repressed information may be for a variety of experiences, fears, or wishes scattered across time. Dissociation is often elicited as a defense, especially after episodes of physical trauma, whereas repression is a response to warded-off fears and wishes or in response to other dynamic conflicts.

^dDissociated information is stored in a discrete and untransformed manner, whereas repressed information is usually disguised and fragmented. Even when repressed information becomes available to consciousness, its meaning is hidden (e.g., in dreams, slips of the tongue).

^eRetrieval of dissociated information often can be direct. Techniques such as hypnosis can be used to access warded-off memories. In contrast, uncovering of repressed information often requires repeated recall trials through intense questioning, psychotherapy, or psychoanalysis with subsequent interpretation (i.e., of dreams).

^fThe focus of psychotherapy for dissociation is integration, via control of access to dissociated states and working through of traumatic memories. The classical psychotherapy for repression involves interpretation, including working through of the transference.

Models and Mechanisms of Dissociation

Dissociation and Information Processing

A study by Williams et al. (2006) using functional magnetic resonance imaging (fMRI) found that many of the same regions of the human brain are activated during conscious attention to signals of fear and in the absence of awareness for these signals. Through fMRI studies with connectivity analysis in healthy human subjects, they were able to demonstrate that level of awareness for signals of fear depends on mode of functional connectivity in amygdala pathways rather than discrete patterns of activation in these pathways. Awareness for fear relied on negative connectivity within both cortical and subcortical pathways to the amygdala, suggesting that reentrant feedback may be necessary to afford such awareness. In contrast, responses to fear in the absence of awareness were supported by positive connections in a direct subcortical pathway to the amygdala, consistent with the view that excitatory feed-forward connections along this pathway may be sufficient for automatic responses to "unseen" fear. These findings may explain how "dissociated or unknown" memory content may exert its effects, by eliciting fear or panic or by triggering altered/dissociated states in victims of trauma.

From a more clinical perspective, dissociation may be explained by one of three proposed models or combinations of these: 1) the neurological model, which suggests that some underlying neurological process, such as hemispheric disconnection or epilepsy, plays a role in promoting dissociative symptoms; 2) the role enactment model or social role demand theory, which suggests that the symptoms are an artificial social construct rather than a true psychiatric disorder; and 3) the autohypnotic model, a theory that recognizes and reconciles the connection between traumatic events, dissociative experiences, and hypnotizability. These models have been described at length elsewhere (Maldonado 2007) and are not discussed here.

Modern research on memory shows that there are at least two broad categories of memory, variously described as explicit and implicit, or episodic and semantic. These two memory systems serve different functions. Explicit (or episodic) memory involves recall of personal experience identified with the self (e.g., "I was at the ball game last week"). Implicit (or semantic) memory involves the execution of routine operations, such as riding a bicycle or typing. Such operations may be carried out with a high degree of proficiency with little conscious awareness of either their current execution or the learning episodes on which the skill is based. Indeed, these two types of memory have different neuroanatomical localizations: the limbic system, especially the hippocampal formation, and mammillary bodies for episodic memory, and the basal ganglia and cortex for semantic memory (Mishkin and Appenzeller 1987).

Indeed, the distinction between these two types of memory may account for certain dissociative phenomena. The automaticity observed in certain dissociative disorders may be a reflection of the separation of self-identification in certain kinds of explicit memory from routine activity in implicit or semantic memory. It is thus not at all foreign to our mental processing to act in an automatic way devoid of explicit self-identification. Were it necessary for us to retrieve explicit memories of how and when we learned all of the activities we are required to perform, it is highly unlikely that we would be able to function with anything like the degree of efficiency we have. Many athletes report focusing on some detail of the event and allowing their bodies to do what they need to, when in fact they are performing extremely well. There is thus a fundamental model in memory research for the dissociation between identity and performance that may well find its pathological reflection in disorders such as dissociative amnesia, fugue, and identity disorder.

Dissociation and Trauma

An important development in the modern understanding of dissociative disorders is the exploration of the link between trauma and dissociation. Trauma can be understood as the experience of being made into an object or a thing, the victim of someone else's rage or of nature's indifference. It is the ultimate experience of helplessness and loss of control over one's own body. Van der Hart et al. (2005) postulated that the process of traumatization involves some degree of division or dissociation of psychobiological systems that constitute personality. By this theory, dissociated parts of the personality avoid traumatic memories and perform functions in daily life, while one or more other parts remain fixated in traumatic experiences and defensive actions. Unfortunately, the dissociated memories may manifest themselves in the form of negative and/or positive dissociative symptoms that must be distinguished from alterations of consciousness.

In fact, there is growing clinical and some empirical evidence that dissociation may occur especially as a defense during trauma—an attempt to maintain mental control at the very moment when physical control has been lost (Dalenberg et al. 2012; Kluft 1984a, 1984b; Putnam 1985; Spiegel 1984; van der Hart et al. 2005). One patient with DID reported "going to a mountain meadow full of wildflowers" when she was being sexually assaulted by her drunken father. She would concentrate on how pleasant and beautiful this imaginary scene was as a way of detaching herself from the immediate experience of terror, pain, and helplessness. Such individuals often report seeking comfort from imaginary playmates or imagined protectors or absorbing themselves in some perceptual distraction, such as the pattern of the wallpaper. Many rape victims report floating above their bodies, feeling sorry for the persons being assaulted beneath them. Children exposed to multiple traumas are more likely than those without a history of trauma to use dissociative defense mechanisms, which include spontaneous trance episodes and amnesia (Williams 1994).

A growing body of scientific literature suggests a connection between a history of physical and sexual abuse in childhood and the development of dissociative symptoms (Chu et al. 1999; Coons and Milstein 1986; Dalenberg et al. 2012; Kluft 1984a; Mulder et al. 1998; Sar et al. 1996; Scroppo et al. 1998; Spiegel 1984). When Mulder et al. (1998) examined the relationship between childhood sexual abuse, childhood physical abuse, current psychiatric illness, and measures of dissociation in an adult population, they found that 6.3% of the abused population had three or more frequently occurring dissociative symptoms. Among these individuals, the rate of childhood sexual abuse was 2.5 times as high, the rate of physical abuse was 5 times as high, and the rate of current psychiatric disorder was 4 times as high as the respective rates for the other subjects. Similarly, a study by Collin-Vezina and Hebert (2005) found that sexual victimization significantly increases the odds of presenting with a clinical level of dissociation and PTSD symptoms by eightfold and fourfold, respectively.

Evidence is accumulating that dissociative symptoms are more prevalent in patients with borderline personality disorder when the individuals have a history of childhood abuse (Spitzer et al. 2006). In a study of 62 women diagnosed with borderline personality disorder, Shearer (1994) found that univariate analyses demonstrated that patients with borderline personality disorder and dissociative experiences have more self-reported traumatic experiences, posttraumatic symptoms, behavioral dyscontrol, self-injurious behavior, and alcohol abuse. The findings also suggested that scores on the Dissociative Experiences Scale (Bernstein and Putnam 1986) were predicted particularly by adult sexual assault, behavioral dyscontrol, and both sexual and physical abuse in childhood. Watson et al. (2006) examined 139 patients with borderline personality disorder and found that their levels of dissociation increased with levels of childhood trauma, supporting the hypothesis that traumatic childhood experiences engender dissociative symptoms later in life. More importantly, these findings suggest that emotional abuse and neglect may be at least as important as physical and sexual abuse in the development of dissociative symptoms.

Johnson et al. (2001) confirmed that peritraumatic dissociation in patients seeking treatment for childhood sexual abuse was strongly related to later development of PTSD, dissociation, and depression. Data analysis indicated that women who experienced penile penetration, who believed someone or something else would be killed, or who were injured as a result of the abuse had more severe peritraumatic dissociation. Regression analyses indicated that peritraumatic dissociation was the only variable to significantly predict symptom severity across symptom type or disorder. Similarly, Hetzel and McCanne (2005) found that different types of childhood abuse may lead to different adult problems. For example, the combined sexual and physical abuse and sexual abuse only groups reported significantly higher numbers of PTSD symptoms compared with the physical abuse only and the no abuse (control) groups. The combined sexual and physical abuse and physical abuse only groups also reported significantly more adult sexual and physical victimization than the sexual abuse only and control groups. The results suggest that across all four groups, higher levels of peritraumatic dissociation were associated with higher levels of PTSD and adult sexual and physical victimization. The authors concluded that peritraumatic dissociation may have a broad effect on PTSD development and adult victimization.

A follow-up study of victims of the World Trade Center disaster found that baseline (peritraumatic) dissociation was the strongest predictor of dissociation at follow-up, whereas baseline posttraumatic stress was the strongest predictor of posttraumatic stress (PTSD) at followup (Simeon et al. 2005). Of the four peritraumatic distress factors generated in the original survey, loss of control and guilt/shame were significantly related to dissociation and posttraumatic stress at follow-up, whereas helplessness/anger was associated only with posttraumatic stress at follow-up. These studies confirmed previous findings by O'Toole et al. (1999) that having been wounded was not related to lifetime or current PTSD, whereas peritraumatic dissociation was related to all diagnostic components of PTSD. Similarly, Olde et al. (2005) found a 2.1% incidence of PTSD in a population of 140 women following childbirth. In their sample, both perinatal negative emotional reactions and perinatal dissociative reactions predicted PTSD symptoms at 3 months postpartum.

The presence of a concomitant dissociative disorder should be considered in victims of traumatic stress. Chronic exposure to trauma can lead not only to anxiety disorders (e.g., acute stress disorder, PTSD) but also to one of the dissociative disorders (Kluft 1984b; Spiegel 1984, 1986; Spiegel and Cardena 1991). In fact, it is uncommon to encounter a patient suffering from a dissociative disorder who has not been previously exposed to intense trauma, usually physical (or sexual) abuse, to the point of also fulfilling Criterion A for the diagnosis of PTSD (American Psychiatric Association 2013). A recent study among war veterans confirmed a direct association between dissociation and PTSD severity and suggests that dissociation is a highly salient facet of posttraumatic psychopathology (Wolfet al. 2012).

Peritraumatic dissociation (i.e., dissociative responses at the time of or immediately after the traumatic event) may predict the development of trauma- and stressor-related disorders sometime in the future (Brewin et al. 2010; Briere et al. 2005). Current theories of trauma-related stress disorder suggest that peritraumatic dissociation causes insufficient encoding of traumatic memories and alterations in memory storage, and that persistent dissociation prevents memory elaboration, leading to partial amnesia, intrusive recollections, and memory fragmentation typical of these disorders (e.g., acute stress disorder, PTSD, dissociative disorder) (Bedard-Gilligan and Zoellner 2012; Brewin et al. 2010; Feeny et al. 2000a, 2000b).

Even though dissociative defenses may work well at the time of trauma, if the defense persists too long, it interferes with the working through (in Lindemann's [1994] terms, the "grief work") that is necessary to put traumatic experience into perspective and reduce the likelihood of later PTSD or other symptomatology (Lindemann 1994; Spiegel 1981). Therefore, psychotherapy aimed at helping individuals acknowledge, bear, and put into perspective traumatic experience shortly after the trauma should be helpful in reducing the incidence of later PTSD.

DSM-5 Dissociative Disorders

Since its introduction in 1952, the Diagnostic and Statistical Manual of Mental Disorders (DSM; American Psychiatric Association 1952) has served as the standard for the diagnostic classification of mental disorders. In 2013, the American Psychiatric Association unveiled the fifth edition of the manual, DSM-5. This new version contains some significant changes regarding dissociative disorders, as summarized in Table 15-2. In this section, we review the epidemiology, diagnostic criteria, and treatment of the dissociative disorders as defined in DSM-5.

Dissociative Identity Disorder

As specified in the DSM-5 diagnostic criteria (Box 15-1), the hallmark of DID is "disruption of identity characterized by [the presence of] two or more distinct personality states, which may be described in some cultures as an experience of possession" (American Psychiatric Association 2013, p. 292). The periods of identity disruption cause "marked discontinuity in sense of self and sense of agency, accompanied by related alterations in affect, behavior, consciousness, memory, perception, cognition, and/or sensory-motor functioning" and lead to gaps in memory and impairments in social and occupational functioning (American Psychiatric Association 2013). By definition, individuals with DID experience recurrent gaps in their recall of routine life events and key personal information (usually of a traumatic nature) that are not consistent with ordinary forgetting (Criterion B). These symptoms are associated with clinically significant distress and functional impairment (Criterion C) and cannot be part of a broadly accepted cultural or religious practice (Criterion D) or caused by organic factors such as substance use or a neurological disorder (Criterion E).

^aLocated in DSM-5 chapter "Trauma- and Stressor-Related Disorders."

The identity temporarily lost during dissociative states or the aspects of the self that are fragmented in DID are two-dimensional aspects of an overall personality structure. In this sense, it has been said that patients with DID suffer not from having more than one personality but rather from having less than one personality. Differences between DSM-IV-TR (American Psychiatric Association 2000) and DSM-5 diagnostic criteria for DID are itemized in Table 15-2.

Prevalence

In a study of community adults, the prevalence of DID was 1.5% (Johnson et al. 2006). Loewenstein (1994) reported that the prevalence of DID in North America is about 1%, compared with a prevalence of 10% for all dissociative disorders as a group. Loewenstein's findings were replicated by Rifkin et al. (1998), who studied 100 randomly selected women, ages 16-50 years, who had been admitted to an acute psychiatric hospital, and found that 1% of the subjects had DID. The estimated prevalence is approximately 3% among psychiatric inpatients (Ross 1991; Ross et al. 1991). Foote et al. (2006) carefully assessed 231 consecutive admissions to an inner-city mental health clinic and interviewed 82 of those willing to cooperate with the study. Of this sample, 29% of patients met DSM-IV criteria for a dissociative disorder (8 with dissociative amnesia, 7 with dissociative disorder not otherwise specified, 5 with DID, and 4 with depersonalization disorder) (American Psychiatric Association 1994). Only 5% of this sample had previously been diagnosed with a dissociative disorder, suggesting systematic underdiagnosis. Furthermore, the study provided additional evidence linking both physical and sexual abuse to dissociative symptoms, determining an odds ratio of 5.86 for physical abuse and 7.87 for sexual abuse.

The number of reported DID cases has risen considerably in recent years. Factors that account for this increase include a more general awareness of the diagnosis among mental health professionals; the availability, starting with DSM-III (American Psychiatric Association 1980), of specific diagnostic criteria; and reduced misdiagnosis of DID as schizophrenia or borderline personality disorder (American Psychiatric Association 1980). Other authors attribute the increase in reported cases to hypnotic suggestion and misdiagnosis (Brenner 1996). Proponents of this point of view argue that individuals with DID are as a group highly hypnotizable and therefore quite suggestible and that a few specialist clinicians usually make the vast majority of diagnoses. However, it has been observed that the symptomatology of patients diagnosed by specialists in dissociation does not differ from that assessed by psychiatrists, psychologists, and physicians in more general practices, who diagnose one or two cases per year. On the other hand, Akyuz et al. (1999) examined the prevalence of DID in the general population of a rural area in Turkey. They found that 1.7% received a diagnosis of dissociative disorder according to a structured interview, and half of these fulfilled clinical criteria for DID, yielding a minimum prevalence of 0.4% for DID. Thus, their data, derived from a population with no public awareness about DID and no exposure to systematic psychotherapy (thus eliminating the possible "iatrogenic contamination factor"), suggest that DID cannot be considered simply an iatrogenic artifact, a culture-bound syndrome, or a phenomenon induced by media influences.

If such patients were so suggestible and subject to directive influence by diagnosticians, then it is surprising that their presenting symptoms persisted for an average of 6.5 years before the diagnosis was made (Putnam et al. 1986). Rather, it would seem likely that such patients would accept a suggestion that they have another disorder, such as schizophrenia, dysthymia, substance use disorder, or borderline personality disorder, because they encounter many clinicians who are unaware of or not familiar with DID. Claims have been made that the widely observed connection between trauma and dissociation is due to fantasy-proneness among individuals who dissociate—that is, that they imagine or are led to imagine histories of abuse. These claims have been systematically examined and found to be inconsistent with the literature documenting histories of abuse, as well as with the accuracy and nature of traumatic memory among those with dissociation (Dalenberg et al. 2012).

The skepticism regarding the existence of DID is compounded in the case of criminals because of issues of suspected malingering. Lewis et al. (1997) reviewed the clinical records of 12 murderers with a DSM-IV-defined diagnosis of DID. Data were gathered from medical, psychiatric, social service, school, military, and prison records and from records of interviews with subjects' family members. In their sample, the researchers were able to independently corroborate the presence of signs and symptoms of DID in childhood and adulthood from several sources in all 12 cases. Furthermore, objective evidence of severe abuse was obtained in 11 cases. Of interest, most subjects had amnesia for most of the abuse and thus underreported it. Marked changes in writing style and/or signatures were documented in 10 cases.

Course

Although DID is diagnosed in childhood with increasing frequency, it typically presents as a clinical entity between adolescence and the third decade of life (Kluft 1984a). Symptoms of DID usually present before the age of 40 years, although there is often considerable delay between initial symptom presentation and diagnosis (American Psychiatric Association 2000; Putnam et al. 1986). The female-to-male sex ratio of DID is 5:4 in children and adolescents and 9:1 in adults (Sno and Schalken 1999).

Untreated, DID is a chronic and recurrent disorder. It rarely remits spontaneously, but the symptoms may not be evident for some time (Kluft 1985c). DID has been called "a pathology of hiddenness" (Kluft 1988). The dissociation itself hampers self-monitoring and accurate reporting of symptoms. Many patients with the disorder are not fully aware of the extent of their dissociative symptomatology. They may be reluctant to bring up symptoms because of having encountered frequent skepticism. Furthermore, because most patients with DID report histories of sexual and physical abuse, the shame associated with a history of abuse, as well as fear of retribution, may also inhibit reporting of symptoms (Coons et al. 1988; Kluft 1988; Putnam 1988; Putnam et al. 1986; Ross 1989; Spiegel 1984).

Treatment

In a systematic review, Brand et al. (2009) included eight nonrandomized treatment outcome studies for the same patient population. These studies provide preliminary evidence that treatment is effective in reducing a range of symptoms associated with dissociative disorders, including depression, anxiety, Axis I and Axis II diagnoses, and dissociative symptoms. Despite suggesting positive results, the findings are tempered by the lack of randomization, selection bias, high dropout rates, and small sample sizes.

Psychotherapy

Therapeutic guidelines. Psychotherapy can help patients with DID gain control over the dissociative process underlying their symptoms. The fundamental psychotherapeutic stance should involve meeting patients halfway in the sense of acknowledging that they experience themselves as fragmented, yet the reality is that the fundamental problem is a failure of integration of disparate memories and aspects of the self. Therefore, the goal in therapy is to facilitate integration of disparate elements. This can be done in a variety of ways.

Secrets are frequently a problem with DID patients, who attempt to use the therapist to reinforce a dissociative strategy that withholds relevant information from certain personality states. Such patients often like to confide plans or stories—for example, traumatic memories or plans for self-destructive activities—to the therapist with the idea that the information is to be kept from other parts of the self. It is important for the therapist to set clear limits and to be committed to helping all portions of a patient's personality structure to learn about warded-off information. It is wise for the therapist to clarify explicitly that he or she will not become involved in secret collusion. Furthermore, when important agreements are negotiated, such as a commitment on the part of the patient to seek medical help before acting on a thought to harm self or others, the clinician should discuss with the patient that this is an "all-points bulletin"—that is, one that requires attention from all the relevant personality states. The patient's excuse that certain personality states were "not aware" of the agreement should not be accepted.

For example, a patient with DID who had been in treatment for many years demonstrated a new alter who threatened to arrange for an apparently accidental death. The therapist told the alter that he, the therapist, would have to share this information with the other personalities. "You can't do that," the alter replied. "That would violate doctor-patient confidentiality." Suppressing a smile, the therapist explained that confidentiality did not apply between identities.

Maldonado et al. (2002) described a series of considerations (Table 15-3) to be used in the treatment of DID. These guidelines were designed to facilitate the therapist-patient contract by establishing clear lines of communication, delineating therapeutic boundaries, eliminating splitting, and enhancing control over dissociative experiences.

Hypnosis. Hypnosis can be helpful in therapy as well as in diagnosis (Kluft 1985a, 1985b, 1985c; Maldonado and Spiegel 1998; Maldonado et al. 2002; Spiegel and Spiegel 2004). The simple structure of hypnotic induction may elicit dissociative phenomena. For example, the Hypnotic Induction Profile (Spiegel and Spiegel 2004) was administered to a woman who had experienced hysterical pseudoseizures. In the middle of a routine induction, her head suddenly turned to the side and she relived with considerable affect, as if it were happening in present tense, an episode in which she had been abducted and sexually assaulted. This enabled her and the clinician to reanalyze her symptoms as spontaneous dissociation, similar to the hypnotic state she had been in. The capacity to elicit such symptoms on command provides the first hint of the ability to control these symptoms. Most of these patients have the experience of being unable to stop dissociative symptoms but are often intrigued by the possibility of starting them, because this carries with it the potential for changing or stopping the symptoms as well.

Source. Maldonado et al. 2002.

Hypnosis can be helpful in facilitating access to dissociated personalities. The personalities may simply occur spontaneously during hypnotic induction. An alternative strategy is to hypnotize the patient and use age regression to help the patient reorient to a time when a different personality state was manifest. An instruction later to change back to the present time usually elicits a return to the other personality state. This then becomes an alternative means of teaching the patient control over the dissociation.

Alternatively, entering the state of hypnosis may make it possible to simply "call up" different identities or personality states. Patients can be taught a simple self-hypnosis exercise. For example, the patient can be instructed to do the following:

Count silently from 1 to 3: On 1, do one thing: look up. On 2, do two things: slowly close your eyes, and take a deep breath. On 3, do three things: let the breath out, let your eyes relax but keep them closed, and let your body float. Then let one hand float up into the air like a balloon. Develop a pleasant sense of floating throughout your body.

Following use of formal exercises such as this, it is often possible for the therapist to simply ask to speak with a given alter personality, without the formal use of hypnosis. After some training, a therapist may simply call up a given "identity state" (e.g., "the part of you that felt hurt") as opposed to a specific "person" (e.g., an alter who identifies herself as "Lucy" when the patient's given name is Barbara). The reason for using a particular identity state rather than a specific name to address an alter is that fostering a relationship with each personality state (which the patient identifies as a distinctive "person" or entity) serves to promote integration of these dissociated or fragmented personality states.

Memory retrieval. Because loss of memory in DID is complex and chronic, retrieval of memory is likewise a more extended and integral part of the psychotherapeutic process. The therapy becomes an integrating experience of information sharing among disparate personality elements. In conceptualizing DID as a chronic PTSD, the psychotherapist can focus on working through traumatic memories in addition to controlling the dissociation.

Controlled access to memories greatly facilitates psychotherapy. As in the treatment of dissociative amnesia (discussed later in this chapter), a variety of strategies can be used to help DID patients break down amnesic barriers. Use of hypnosis to go to that place in imagination and ask one or more such parts of the self to interact can be helpful.

Once these memories of earlier traumatic experiences have been brought into consciousness, it is crucial to help the patient work through the painful affect, inappropriate self-blame, and other reactions to these memories. A model of grief work is helpful, enabling the patient to acknowledge and bear the import of such memories (Lindemann 1994; Spiegel 1981). It may be useful to have the patient visualize the memories rather than relive them as a way of making their intensity more manageable. It also can be useful to have the patient divide the memories onto two sides of an imaginary screen—for example, on one side, picturing something an abuser did to him or her, and on the other side, picturing how the patient tried to protect him- or herself from the abuse.

A young woman with DID remembered a particularly painful episode in hypnosis. When she was 12 years old, her stepfather smoked a good deal of marijuana and then forced her to have oral sex with him. She recalled being repelled by what he was forcing her to do and then remembered that she had gagged and vomited all over him. "I spoiled his fun. He threw me up against a wall, but it did not bother me a bit because I knew I ruined it for him." She was instructed to picture on one side of the screen what he had done to her and on the other what she had done to him.

Such techniques can help make the traumatic memories more bearable by placing them in a broader perspective, one in which the trauma victim also can identify adaptive aspects of his or her response to the trauma.

This technique and similar approaches can help these individuals work through traumatic memories, enabling them to bear the memories in consciousness and therefore reducing the need for dissociation as a means of keeping such memories out of consciousness. Although these techniques can be helpful and often result in reduced fragmentation and integration, several complications can occur in the psychotherapy of these patients as well (Kluft 1985a, 1985b, 1986, 1992; Maldonado and Spiegel 1998; Spiegel 1984, 1986).

The information retrieved from memory in these ways should be reviewed, traumatic memories put into perspective, and emotional expression encouraged and worked through, with the goal of sharing the information as widely as possible among various parts of the patient's personality structure. Instructing other alter personalities to "listen" while a given alter is talking, and reviewing previously dissociated material uncovered, can be helpful. The therapist conveys his or her desire to disseminate the information, without accepting responsibility for transmitting it across all personality boundaries.

"Rule of thirds." Psychotherapy with a DID patient can be a time-consuming and emotionally taxing process. The "rule of thirds" is a helpful guideline (Kluft 1988). The therapist should spend the first third of the psychotherapy session assessing the patient's current mental state and life problems and defining a problem area that might benefit from retrieval into conscious memory and working through. The therapist should spend the second third of the session accessing and working through this memory. The therapist should allow a final third for helping the patient assimilate the information, regulate and modulate emotional responses, and discuss any responses to the therapist and plans for the immediate future.

It is wise to use this final third of the session for debriefing and helping the patient to reorient, to attempt to integrate the new material, to transmit information across personalities, and to prepare to terminate the session. The therapist may resist doing this because the intense abreacted materials are often so compelling and interesting. Also, the patient may resist sharing of information across personalities.

Given the intensity of the material that often emerges involving memories of sexual and physical abuse, and the sudden shifts in mental state accompanied by amnesia, the therapist is called on to take a clear and structured role in managing the psychotherapy. Appropriate limits must be set about self-destructive or threatening behavior and agreements made regarding physical safety and treatment compliance, and other matters must be presented to the patient in such a way that dissociative ignorance is not an acceptable explanation for failure to live up to agreements.

Traumatic transference. Transference applies with special meaning in patients who have been physically and sexually abused. These patients have had presumed "caregivers" who acted instead in an exploitative and sometimes sadistic fashion. These patients thus expect the same from their therapists. Although their reality testing is good enough that they can perceive genuine caring, they expect therapists either to exploit them, with the patients viewing the working through of traumatic memories as a reinflicting of the trauma and the therapists' taking sadistic pleasure in the patients' suffering, or to be excessively passive, with the patients identifying the therapists with some uncaring family figure who knew abuse was occurring but did little or nothing to stop it. It is important in managing the therapy to keep these issues in mind and make them frequent topics of discussion. Attention to these issues can diffuse, but not eliminate, such traumatic transference distortions of the therapeutic relationship (Maldonado and Spiegel 1998).

Integration. The ultimate goal of psychotherapy for patients with DID is integration of the disparate states. They might have considerable resistance to this process. Early in therapy, the patient views the dissociation as tremendous protection: "I knew my father could get some of me, but he couldn't get all of me." Indeed, the patient may experience efforts of integration as an attempt on the part of the therapist to "kill" personalities. These fears must be worked through and the patient shown how to control the degree of integration, giving the patient a sense of gradually being able to control his or her dissociative processes in the service of working through traumatic memories. The process of the psychotherapy, in emphasizing control, must alter rather than reinforce the content, which involves the reexperiencing of helplessness, a symbolic reenactment of trauma.

As previously mentioned, a patient with DID often fears integration as an attempt to "kill" alter personalities and make the patient more vulnerable to mistreatment by depriving him or her of the dissociative defense. At the same time, this defense represents an internalization of the abusive person or persons in the patient's memory. Setting aside the defense also means acknowledging and bearing the discomfort of helplessness at having been victimized and working through the irrational self-blame that gave the patient a fantasy of control over events that he or she was in fact helpless to control. Difficult as it is, however, the ultimate goal of psychotherapy is mastery over the dissociative process, controlled access to dissociative states, integration of warded-off painful memories and material, and a more integrated continuum of identity, memory, and consciousness (Maldonado and Spiegel 1998). Although there have been no controlled trials of psychotherapy outcome in patients with this disorder, systematic reviews of case series reports indicate a moderate to large effect size in positive outcome, and demonstrate that integration is associated with better symptom reduction in most cases (Brand et al. 2009, 2012; Kluft 1984b, 1991).

Legal considerations. The Council on Scientific Affairs of the American Medical Association convened a panel of experts to examine the research evidence relevant to the effect of hypnosis on memory and recall. The panel concluded that what evidence exists indicates that the use of hypnosis tends to increase the productivity of witnesses, resulting in new memories, some of which are true and some of which are incorrect (Council on Scientific Affairs 1985). Furthermore, some studies showed an increase in the confidence assigned by hypnotized subjects to their memories despite the fact that the percentage of correct responses had not improved. The panel noted that the analogy between the laboratory setting in which most of the studies were done and the real-life situation in the courtroom must be drawn with great caution and that situations in which extreme emotional and physical trauma have occurred differ markedly. The panel recommended that careful guidelines similar to the ones outlined in the California law be followed when hypnosis is used in the forensic setting (Council on Scientific Affairs 1985). Similarly, the "FBI Guidelines for Use of Hypnosis" (Ault 1979) detailed the parameters and rules to follow in order to maximize the yield of hypnotic recollection while preserving the integrity of the process.

Hypnosis is clearly not a truth serum, and the courts must weigh the effects of any hypnotic induction on a witness. At the same time, hypnosis may in certain cases help a traumatized and amnesic witness to recall details not brought forward through conventional interrogation methods. Despite the former popularity of hypnosis as a way of "improving" eyewitness memory, many courts almost always regard the use of this testimony to be inadmissible, whereas others allow it only when strict procedural guidelines have been followed. Although the U.S. Supreme Court recognized a defendant's constitutional right to admit his or her own hypnotically elicited testimony, other courts have recognized a constitutional basis to exclude hypnotically elicited testimony in most other circumstances (Newman and Thompson 1999).

Maldonado (2007; Maldonado and Spiegel 2008) summarized and adapted the guidelines provided by the American Medical Association ("Scientific Status of Refreshing Recollection by the Use of Hypnosis" [Council on Scientific Affairs 1985]) and the American Society of Clinical Hypnosis (Hammond 1995) for the use of hypnosis as a method of memory enhancement. The guidelines suggest that when hypnosis or any other memory enhancement method is being used for forensic purposes or in the context of working out traumatic memories, especially those related to childhood physical and/or sexual abuse, the steps shown in Table 15-4 should be applied.

Source. Maldonado JR: "Diagnosis and Treatment of Dissociative Disorders," in Manual for the Course "Advanced Hypnosis: The Use of Hypnosis in Medicine and Psychiatry." Presented at 153rd annual meeting of the American Psychiatric Association, Chicago, IL, May 13-18, 2000.

Cognitive-behavioral approaches. Fine (1999) summarized the tactical-integration model for the treatment of dissociative disorders. This model consists of structured cognitive-behavioral-based treatments that foster symptom relief, followed by integration of the personalities and/or ego states into one mainstream of consciousness. This approach promotes proficiency in control over posttraumatic and dissociative symptoms, is collaborative and exploratory, and conveys a consistent message of empowerment to the patient.

In addition, both cognitive analytic therapy (CAT) (Kellett 2005; Ryle and Fawkes 2007) and dialectical behavioral therapy (DBT) (Braakmann et al. 2007) have been found to be helpful as adjunctive or primary treatment of patients with DID. In CAT, multiplicity is understood in terms of a range of self-other patterns (i.e., reciprocal role relationships) originating in childhood. These patterns alternate in determining experience and action according to the situation (i.e., contextual multiplicity). They may be restricted by adverse childhood experiences (i.e., diminished multiplicity), and severe deprivation or abuse may result in a structural dissociation of self-processes (i.e., pathological multiplicity). In CAT practice, descriptions of dysfunctional relationship patterns and of transitions between them are worked out by therapist and patient at the start of therapy and are used by both throughout its course (Ryle and Fawkes 2007).

A study using DBT found that patients with high preintervention levels of dissociation achieved the greatest relative symptom reduction (Braakmann et al. 2007). These results are explained by the DBT treatment setting, which includes specific psychoeducation and treatment concerning dissociative behavior.

Psychopharmacology

To date, no good evidence shows that medication of any type has a direct therapeutic effect on the dissociative process manifested by patients with DID (Loewenstein 2006; Putnam 1989). In fact, most dissociative symptoms seem relatively resistant to pharmacological intervention (Loewenstein 1994, 2006). Thus, pharmacological treatment has been limited to the control of signs and symptoms afflicting patients with DID or comorbid conditions rather than the treatment of dissociation per se. In fact, the most recent review of the literature yielded 21 case studies and 80 empirical studies, presenting data on 1,171 new cases of DID, but shed no light on effective treatments (Boysen and Vanbergen 2013). Similarly, recently published "guidelines" add little to the pharmacological management of DID (International Society for the Study of Trauma and Dissociation 2011).

Whereas in the past, short-acting barbiturates such as sodium amobarbital were used intravenously to reverse functional amnesias, this technique is no longer used, largely because of poor results. Benzodiazepines have at times been used to facilitate recall through controlling secondary anxiety associated with retrieval of traumatic memories. However, these effects may be nonspecific at best. Furthermore, the sedative and amnestic properties of these agents, and the fact that they may elicit a sudden transition in mental state, may increase rather than decrease amnesic barriers and the patient's sense of lack of control. Thus, inducing state changes pharmacologically could in theory add to difficulty in retrieval and behavioral dyscontrol. The only systematic study on the use of benzodiazepines in patients with DID was conducted by Loewenstein and Putnam (1988). In their study, they used clonazepam successfully to control PTSD-like symptoms in a small sample (n=5) of DID patients, achieving improvement in sleep continuity and a decrease in frequency of flashbacks and nightmares.

Antidepressants are the most useful class of psychotropic agents for patients with DID. Such patients frequently have dysthymic disorder or major depression as well as DID, and when these disorders are present, especially with somatic signs and suicidal ideation, antidepressant medication can be helpful. At least two studies report on the successful use of antidepressant medications (Barkin et al. 1986; Kluft 1984b). The use of antidepressants should be limited to the treatment of DID patients who experience symptoms of major depression (Barkin et al. 1986). The selective serotonin reuptake inhibitors are effective at reducing comorbid depressive symptoms and have the advantage of far less lethality in overdose compared with tricyclic antidepressants and monoamine oxidase inhibitors. Medication compliance is a problem with such patients because dissociated personality states may interfere with the taking of medication by the "hiding" or hoarding of pills, or patients may overdose.

Antipsychotics are rarely useful in reducing dissociative symptoms. They are used occasionally for containing impulsive behavior, with varying effect. More often, they are used with little benefit when patients with DID have been given misdiagnoses of schizophrenia (Kluft 1987, 1988). In addition to the risks of side effects, such as tardive dyskinesia, the neuroleptics may reduce the range of affect, thereby making patients with DID look spuriously as though they were schizophrenic. In fact, most DID researchers have reported an extremely high incidence of adverse side effects with the use of neuroleptic medications (Barkin et al. 1986; Kluft 1984b, 1988; Putnam 1989; Ross 1989).

Anticonvulsants have been used to treat seizure disorders (Mesulam 1981; Schenk and Bear 1981), which have a high rate of comorbidity with DID; mood disorders; and the impulsiveness associated with personality disorders. These agents have been used to reduce impulsive behavior but are rarely definitively helpful. The high incidence of serious side effects and abuse or overdose potential also should be kept in mind.

Dissociative Amnesia

As specified in the DSM-5 diagnostic criteria (Box 15-2), the hallmark of dissociative amnesia is the inability to recall important personal information, usually of a traumatic or stressful nature, that cannot be explained by ordinary forgetfulness, in the absence of overt brain pathology or substance use (American Psychiatric Association 2013). The main difference between the diagnostic criteria in DSM-5 and those in DSM-IV-TR is clarification of Criterion A to allow for the presence of either 1) localized or selective amnesia for a specific event or events or 2) generalized amnesia for identity and life history. In addition, DSM-5 reduced the former diagnosis of dissociative fugue to a subtype of dissociative amnesia, designated by the specifier "with dissociative fugue" (i.e., purposeful travel or bewildered wandering) (see Box 15-2).

Dissociative amnesia is considered the most common of the dissociative disorders. Amnesia is a symptom commonly found in several other dissociative and anxiety disorders, including acute stress disorder, PTSD, somatization disorder, and DID (American Psychiatric Association 2013). A higher incidence of dissociative amnesia has been described in the context of war and natural and other disasters (Maldonado et al. 2002). There appears to be a direct relationship between the severity of the exposure to trauma and the incidence of amnesia. Dissociative amnesia is the classical functional disorder of memory and involves difficulty in retrieving discrete components of autobiographical-episodic memory (Kritchevsky et al. 2004; Spiegel et al. 2011). It does not, however, involve a difficulty in memory storage, as in Wemicke-Korsakoff syndrome. Because the amnesia primarily involves difficulties in retrieval rather than encoding or storage, the memory deficits usually are reversible. Once the amnesia has cleared, normal memory function is resumed (Schacter et al. 1996). Dissociative amnesia has three primary characteristics:

1. The memory loss is episodic. The first-person recollection of certain events is lost, rather than Icnowledge of procedures.
2. The memory loss is for a discrete period of time, ranging from minutes to years. It is not vagueness or the inefficient retrieval of memories, but rather a dense unavailability of memories that had been clearly accessible. Unlike in the amnestic disorders, such as from damage to the medial temporal lobe in surgery, or in Wemicke-Korsakoff syndrome, there is usually no difficulty in learning new episodic information. Thus, the amnesia is typically retrograde rather than anterograde (Kritchevsky et al. 2004; Loewenstein 1991), with one or more discrete periods of past information becoming unavailable. However, Kluft (1988) observed a dissociative syndrome of continuous difficulty in incorporating new information that mimics organic amnestic syndromes.
3. The memory loss is generally for events of a traumatic or stressful nature. In one study, the majority of cases involved child abuse (60%), but disavowed behaviors such as marital problems, sexual activity, suicide attempts, criminal behavior, and the death of a relative can also be precipitants (Coons and Milstein 1986).

Dissociative amnesia is most common in the third and fourth decades of life (Coons and Milstein 1986). It usually involves one episode, but multiple periods of lost memory are not uncommon. Comorbidity with conversion disorder, bulimia, alcohol abuse, and depression is common, and Axis II diagnoses of histrionic, dependent, and borderline personality disorders occur in a substantial minority of such patients (Coons and Milstein 1986). Legal difficulties, such as driving under the influence of alcohol, also accompany dissociative amnesia in a minority of cases. Occasionally, there maybe a history of head trauma. If that is the case, usually the trauma is too slight to have neurophysiological consequences. The population prevalence of dissociative amnesia is 1.8% (Johnson et al. 2006).

Dissociative amnesia usually involves discrete boundaries around the period of time unavailable to consciousness. Individuals with such a disorder lose the ability to recall what happened during a specific time. They demonstrate not vagueness or spotty memory but rather a loss of any episodic memory for a finite period. Such individuals initially may not be aware of the memory loss—that is, they may not remember that they do not remember. However, they may find, for example, new purchases in their homes but have no memory of having obtained them. They report being told that they have done or said things that they cannot remember. Some individuals do experience episodes of selective amnesia, usually for specific traumatic incidents, which may be more interwoven with periods of intact memory. In these cases, the amnesia is for a type of material remembered rather than for a discrete period of time.

Despite the fact that certain information is kept out of consciousness in dissociative amnesia, such information may exert an influence on consciousness. For example, a rape victim with no conscious recollection of the assault will nonetheless behave like someone who has been sexually victimized. Such individuals often show detachment and demoralization, are unable to enjoy intimate relationships, and show hyperarousal to stimuli reminiscent of the trauma. This phenomenon is similar to priming in memory research. Minutes or hours after reading a word list, individuals will complete a word stem for a word from the list (e.g., the stem pre for the word prepare) more quickly than they would for a word they have not recently seen. This phenomenon occurs even though they cannot consciously recall having recently read the word that constitutes the prime. Similarly, individuals instructed in hypnosis to forget having seen a list of words will nonetheless show priming effects from the hypnotically suppressed list. It is the essence of dissociative amnesia that material being kept out of conscious awareness is nonetheless active and may influence consciousness indirectly: out of sight does not mean out of mind.

Individuals with dissociative amnesia generally do not have disturbances of identity, except to the extent that their identity is influenced by the warded-off memory. It is not uncommon for such individuals to develop depressive symptoms as well, especially when the amnesia is in the wake of a traumatic episode. However, those with the fugue subtype of dissociative amnesia may suffer more pervasive amnesia for personal identity, sometimes coupled with aimless wandering or purposeful travel.

Treatment

To date, no controlled studies have addressed the treatment of dissociative amnesia. No established pharmacological treatments are available, except for the use of benzodiazepines or barbiturates for drug-assisted interviews (Maldonado et al. 2002). Most cases of dissociative amnesia revert spontaneously, especially when the individuals are removed from stressful or threatening situations, when they feel physically and psychologically safe, and/or when they are exposed to cues from the past (e.g., family members) (Loewenstein 1991; Maldonado et al. 2002). When a safe environment is not enough to restore normal memory functioning, the amnesia sometimes can be breached using techniques such as pharmacologically mediated interviews (i.e., using barbiturates and benzodiazepines) (Perry and Jacobs 1982).

On the other hand, most patients with dissociative disorders are highly hypnotizable on formal testing and therefore are easily able to make use of hypnotic techniques such as age regression (Spiegel and Spiegel 2004). Patients are hypnotized and instructed to experience a time before the onset of the amnesia as though it were the present. Then the patients are reoriented in hypnosis to experience events during the amnesic period. Hypnosis can enable such patients to reorient temporally and therefore to achieve access to otherwise dissociated memories. If the warded-off memory has traumatic content, patients may abreact (i.e., express strong emotion) as these memories are elicited, and they will need psychotherapeutic help in integrating these memories and the associated affect into consciousness.

One technique that can help bring such memories into consciousness while modulating the affective response to them is the split screen technique (Spiegel and Spiegel 2004). In this approach, patients are taught, by using hypnosis, to relive the traumatic event as if they were watching it on an imaginary movie or television screen. This technique is often helpful for individuals who are unable to relive the event as if it were occurring in the present tense, either because that process is too emotionally taxing or because they are not sufficiently hypnotizable to be able to engage in hypnotic age regression. The split screen technique can also be used to provide dissociation between the psychological and the somatic aspects of the memory retrieval. Individuals can be put into self-hypnosis and instructed to get their bodies into a state of floating comfort and safety. They are reminded that no matter what they see on the screen, their bodies will be safe and comfortable.

A victim of a violent attempted rape had developed a selective amnesia for much of the physical struggle itself. She had sustained a basilar skull fracture, but she had not been rendered unconscious. She also had a generalized seizure shortly after the assault. She initially sought help with hypnosis in an attempt to improve her recollection of the assailant's face.

The woman was instructed in use of the split screen technique and used it to relive the assault. She remembered two things that she had not previously recalled: 1) the assailant was surprised at how hard she was fighting with him, and 2) she recognized that he intended not merely to rape her but to kill her. She became convinced that had she let him drag her into her apartment, she likely would not have survived. She was tearful and frightened as she recalled this aspect of the assault that had been previously unavailable to consciousness.

She was then instructed to divide the imaginary screen in half, picturing on the left side an image of the viciousness and intensity of the assault and recognizing on the other side what she had done to protect herself. She was instructed to concentrate on these two aspects of the assault and then, when she was ready, to bring herself out of the state of self-hypnosis. She was told that she could use this as a self-hypnosis exercise several times a day if she wished, as a means of putting her memories of the rape into perspective. This cognitive and emotional restructuring of the traumatic memories made them more bearable in consciousness.

Before this psychotherapy, she had blamed herself for having fought so hard that she was seriously injured. Afterward, she recognized that she may have saved her life by fighting off the assailant so vigorously. This positive therapeutic outcome occurred despite the fact that she was unable to recall any new details about the assailant's physical appearance.

Psychotherapy for dissociative amnesia involves accessing the dissociated memories, working through affectively loaded aspects of these memories, and supporting the patient through the process of integrating these memories into consciousness.

Depersonalization/Derealization Disorder

As specified in the DSM-5 diagnostic criteria (Box 15-3), the essential feature of depersonalization/derealization disorder is the presence of depersonalization (i.e., persistent feelings of unreality, detachment, or estrangement from oneself or one's body, usually with the feeling that one is an outside observer of one's own mental processes), derealization (i.e., experiences of unreality or detachment with respect to surroundings), or both. Of note, Criterion A allows for the presence of either or both phenomena. Clinically, depersonalization is characterized by a profound disruption of self-awareness, mainly involving feelings of disembodiment and subjective emotional numbing (Sierra and David 2011; Spiegel et al. 2011). When derealization co-occurs with depersonalization, individuals experience an altered perception of their surroundings in which the world seems unreal or dreamlike. Affected individuals often will ruminate about this alteration and be preoccupied with their own somatic and mental functioning.

Thus, depersonalization/derealization disorder is primarily a disturbance in the integration of perceptual experience. Individuals with the disorder are distressed by it. Different from those with delusional disorders and other psychotic processes, those with depersonalization/derealization disorder have intact reality testing. Patients are aware of some distortion in their perceptual experience and therefore are not delusional. The symptoms are often transient and may co-occur with a variety of other symptoms, especially anxiety, panic, or phobic symptoms. Indeed, the content of the anxiety may involve fears of "going crazy." Other than the addition of derealization as a diagnostic feature (Criterion A), there are no significant differences between the DSM-5 version and previous criteria.

Hunter et al. (2004) conducted a study using computerized databases and citation searches to assess the prevalence of symptoms of depersonalization and derealization in both clinical and nonclinical settings. They found that transient symptoms of depersonalization and derealization are common in the general population, with a lifetime prevalence rate of between 26% and 74% and a current prevalence rate of between 31% and 66% at the time of a traumatic event. Community surveys employing standardized diagnostic interviews revealed rates of between 1.2% and 1.7% for 1-month prevalence of symptoms of depersonalization or derealization in a U.K. sample and a 2.4% current prevalence rate in a Canadian sample. Current prevalence rates between 1% and 16% were reported in samples of consecutive inpatient admissions, although these rates were considered to be underestimates. Prevalence rates in clinical samples of specific psychiatric disorders varied between 30% (for war veterans with PTSD) and 60% (for those with unipolar depression). There was a high prevalence of depersonalization and derealization symptoms within panic disorder samples, with rates varying from 7.8% to 82.6%.

Depersonalization as a symptom is seen in several psychiatric and neurological disorders. Unlike other dissociative disorders, the presence of which excludes other mental disorders such as schizophrenia and substance abuse, depersonalization disorder frequently co-occurs with such disorders. It is often a symptom of anxiety disorders and PTSD. In fact, about 69% of patients with panic disorder experience depersonalization or derealization during their panic attacks (Ball et al. 1997). Episodes of depersonalization also may occur as a symptom of alcohol and drug abuse, as a side effect of prescription medication, and during stress and sensory deprivation. Depersonalization is considered a disorder when it is a persistent and predominant symptom. The phenomenology of the disorder involves both the initial symptoms themselves and the reactive anxiety caused by them. In a recent study of community adults, the prevalence of depersonalization disorder was 0.8% (Johnson et al. 2006).

Treatment

Depersonalization and derealization are often transient and may remit without formal treatment. Recurrent or persistent depersonalization and derealization should be thought of both as symptoms in and of themselves and as symptoms existing within another syndrome that may require treatment, such as an anxiety disorder or schizophrenia.

Treatment modalities used (Maldonado et al. 2002) include behavioral techniques such as paradoxical intention, record keeping, positive reward, flooding, psychotherapy (especially psychodynamic), cognitive-behavioral therapy, and psychoeducation. Hunter et al. (2005) reported on an open study in which 21 patients with depersonalization disorder were treated individually with cognitive-behavioral therapy. The authors reported significant improvements in patient-defined measures of depersonalization/derealization severity as well as in standardized measures of dissociation, depression, anxiety, and general functioning at the end of treatment and at 6-month follow-up.

Depersonalization/derealization disorder symptoms may respond to selfhypnosis training. Often, hypnotic induction will induce transient depersonalization/derealization symptoms in susceptible subjects. This is a useful exercise because by having a structure for inducing the symptoms, one provides patients with a context for understanding and controlling them. The symptoms are presented as a spontaneous form of hypnotic dissociation that can be modified. Individuals for whom this approach is effective can be taught to induce a pleasant sense of floating lightness or heaviness in place of the anxiety-related somatic detachment. Often, the use of an imaginary screen to picture problem material in a way that detaches it from the typical somatic response is also helpful (Spiegel and Spiegel 2004).

Virtually all types of psychotropic medications, including psychostimulants, antidepressants, antipsychotics, anticonvulsants, and benzodiazepines, have been tried with modest success in individuals with depersonalization or derealization symptoms. Appropriate treatment of comorbid disorders—antianxiety medications for generalized anxiety, panic, or phobic disorders; antidepressants for treatment of comorbid depression or anxiety; and antipsychotic medications for true psychosis—is an important part of treatment. More recently, authors reported on the first clinical trial of repetitive transcranial magnetic stimulation (rTMS) in depersonalization disorder (Mantovani et al. 2011). They found that after 3 weeks of right temporoparietal junction (TPJ) rTMS, 6 of 12 patients responded. Five responders received 3 more weeks of right TPJ rTMS, showing 68% symptom improvement. This preliminary study suggests that right TPJ rTMS may be a safe and effective alternative in the management of depersonalization/derealization disorder.

Other Specified Dissociative Disorder

As described in DSM-5 text (Box 15-4), the "other specified" category has been carved out to include presentations in which symptoms characteristic of a dissociative disorder cause clinically significant distress or dysfunction but do not meet full criteria for any of the disorders in the dissociative disorders diagnostic class (American Psychiatric Association 2013). DSM-5 suggests that in order to facilitate communication among clinicians, the appropriate use of this category requires that following this diagnosis (i.e., "other specified dissociative disorder"), the specific syndrome exhibited is also documented (e.g., "identity disturbance due to prolonged political imprisonment"). Specific examples and details of circumstances where this diagnostic category should be used (e.g., identity disturbance associated with torture, brainwashing, cult indoctrination) are listed in Box 15-4. Of note, acute dissociative reactions to stressful events that are transient (lasting from a few hours up to 30 days) but fall short of meeting DSM-5 acute stress disorder diagnostic criteria are also included here. Finally, dissociative trance (i.e., an acute narrowing or complete unawareness of immediate surroundings, manifested by profound unresponsiveness to environmental stimuli, with or without involuntary stereotyped behaviors, transient paralysis, or loss of consciousness) is likewise included within this designation, as long as the trance condition does not occur solely as a normal part of a broadly accepted collective cultural or religious practice.

Unspecified Dissociative Disorder

As described in DSM-5 text (Box 15-5), the "unspecified" category applies to presentations in which symptoms characteristic of a dissociative disorder cause clinically significant distress or functional impairment but do not meet full criteria for any of the disorders in the dissociative disorders diagnostic class; however, in contrast to the "other specified" category, the "unspecified" designation is used when the clinician chooses not to specify the reason that criteria are not met for a specific disorder or in cases where there is insufficient information to make a more specific diagnosis (e.g., emergency room settings).

Conclusion

The dissociative disorders constitute a challenging component of psychiatric illness. The failure of integration of consciousness, memory, identity, emotion, perception, body representation, motor control, and behavior observed in these conditions results in symptomatology that illustrates fundamental problems in the organization of mental processes. Dissociative phenomena often occur during and after physical trauma but also may represent transient or chronic patterns of maladjustment. Dissociative disorders are generally treatable and constitute a domain in which psychotherapy is a primary modality, although pharmacological treatment of comorbid conditions such as depression can be quite helpful. The dissociative disorders are ubiquitous throughout the world, although they take a variety of forms. These disorders represent a fascinating window into the organization and processing of identity, memory, perception, and consciousness, and they pose a variety of diagnostic, therapeutic, and research challenges.

Key Clinical Points

• Dissociative disorders are often underdiagnosed.
• Dissociation is a common component of acute response to trauma, and dissociative identity disorder, dissociative amnesia, and depersonalization/de-realization disorder often have a traumatic etiology.
• Dissociation represents a failure of integration of identity, memory, perception, and consciousness.
• The primary treatments for dissociative disorders involve various psychotherapies, including hypnosis, trauma-related psychotherapies, and cognitive therapies.
• Common comorbid conditions requiring treatment include depression, substance use disorders, and borderline personality disorder.
• Dissociative symptoms are ubiquitous around the world, but the content of the dissociative symptoms varies, involving presentations that are congruent with cultural idioms, such as "possession" by external entities or fragmentation of individual identity.

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Suggested Readings

Bremner JD, Marmar CA (eds): Trauma, Memory, and Dissociation. Washington, DC, American Psychiatric Press, 1998

Fink G (ed): Encyclopedia of Stress, 2nd Edition. Oxford, UK, Academic Press, 2007

Nathan PE, Gorman JM (eds): A Guide to Treatments That Work, 2nd Edition. New York, Oxford University Press, 2000

van der Kolk BA, McFarlane AC, Weisaeth L (eds): Traumatic Stress: The Effects of Overwhelming Experience on Mind, Body, and Society. New York, Guilford, 1996

Online Resources

International Society for the Study of Trauma and Dissociation: www.isst-d.org

Sidran Traumatic Stress Institute: www.sid-ran.org

Society for Clinical and Experimental Hypnosis: www.sceh.us