The persistence of folly: a critical examination of dissociative identity disorder. Part I. The excesses of an improbable concept

Dissociation and false memory: the moderating role of trauma and cognitive ability

The term dissociation is often used to refer to a diverse range of psychological symptoms, including perceptual impairments, emotional detachment, and memory fragmentation. In the present study, we examined whether there was a relation between participants' self-reports of dissociative experiences and their memory performance in the Deese-Roediger-McDermott (DRM) paradigm-a laboratory-based procedure that is frequently used to investigate false memory. University students (N = 298) completed the Dissociative Experiences Scale (DES) and the Traumatic Life Events Questionnaire (TLEQ). Participants were also administered a standardised intelligence test (Shipley-2), and they were tested in the DRM paradigm. Overall, experiencing trauma and dissociation, as well as lower levels of cognitive ability, were associated with higher false memory. These findings are discussed in the context of the activation monitoring theory of DRM false memory.

Resolution of Dissociated Ego States Relieves Flashback-Related Symptoms in Combat-Related PTSD: A Brief Mindfulness Based Intervention

A novel understanding and therapeutic approach to the treatment of PTSD-related flashback triggers are described. Triggered responses are conceptualized as the result of latent dissociative structures of neural organization and psychodynamic functioning activated by current events. The dissociative structure - here described as a dissociated ego state (DES) - reflects a fracturing of executive functioning resulting in a delimited aspect of self that is not under cognitive control or subject to cognitive inhibition by the self of daily experience, and is the psychological construct behind intrusive PTSD symptoms. Use of a mindful attentional state permits regulated access to the DES (therapeutic engagement without risk of emotional dysregulation) so that dissociated cognitive resources can be recovered and the dissociated structure deactivated. This may relieve maladaptive responses and behaviors associated with the DES in a profound and durable way, without the need for exposure to or recovery of traumatic memories. Based on this understanding, a 9-step intervention is introduced with a case example of a Vietnam veteran suffering PTSD symptoms for 49 years with significant gains maintained at 21 months follow up. These findings demonstrate rapid and durable resolution of chronic PTSD symptoms through a mindfulness-based approach that focused on deactivation of dissociated ego states, in contrast to targeting trauma memories. If proven efficacious, this novel approach may result in reduced treatment costs and improved outcomes for veterans suffering with PTSD.

Predictors of Dissociative Experiences Among Adolescents in Nepal: A Path Analysis

In recent years, many adolescents in Nepal have been affected by episodes of mass psychogenic illness, which seem to involve dissociative symptoms. To identify the potential contributors to dissociation, the present study examined correlates of dissociative experiences among adolescents in Nepal. In a cross-sectional survey, 314 adolescents were assessed with the Adolescent Dissociative Experiences Scale and measures of childhood trauma exposure, as well as cognitive and personality traits found to be associated with dissociation in studies on other populations. Path analysis confirmed that childhood trauma, cognitive and personality traits, and current distress each predicted dissociative experiences and behaviors. However, an integrated path model found that the effect of childhood trauma on dissociation was mediated either by posttraumatic stress symptoms or by cognitive failures. Future studies should develop and test multifactorial models of dissociation and multiple pathways.

Aiding the diagnosis of dissociative identity disorder: pattern recognition study of brain biomarkers

BACKGROUND

A diagnosis of dissociative identity disorder (DID) is controversial and prone to under- and misdiagnosis. From the moment of seeking treatment for symptoms to the time of an accurate diagnosis of DID individuals received an average of four prior other diagnoses and spent 7 years, with reports of up to 12 years, in mental health services.

AIM

To investigate whether data-driven pattern recognition methodologies applied to structural brain images can provide biomarkers to aid DID diagnosis.

METHOD

Structural brain images of 75 participants were included: 32 female individuals with DID and 43 matched healthy controls. Individuals with DID were recruited from psychiatry and psychotherapy out-patient clinics. Probabilistic pattern classifiers were trained to discriminate cohorts based on measures of brain morphology.

RESULTS

The pattern classifiers were able to accurately discriminate between individuals with DID and healthy controls with high sensitivity (72%) and specificity (74%) on the basis of brain structure. These findings provide evidence for a biological basis for distinguishing between DID-affected and healthy individuals.

CONCLUSIONS

We propose a pattern of neuroimaging biomarkers that could be used to inform the identification of individuals with DID from healthy controls at the individual level. This is important and clinically relevant because the DID diagnosis is controversial and individuals with DID are often misdiagnosed. Ultimately, the application of pattern recognition methodologies could prevent unnecessary suffering of individuals with DID because of an earlier accurate diagnosis, which will facilitate faster and targeted interventions.

DECLARATION OF INTEREST

The authors declare no competing financial interests.

Women's Auto/Biography and Dissociative Identity Disorder: Implications for Mental Health Practice

Dissociative Identity Disorder (DID) is an uncommon disorder that has long been associated with exposure to traumatic stressors exceeding manageable levels commonly encompassing physical, psychological and sexual abuse in childhood that is prolonged and severe in nature. In DID, dissociation continues after the traumatic experience and produces a disruption in identity where distinct personality states develop. These personalities are accompanied by variations in behaviour, emotions, memory, perception and cognition. The use of literature in psychiatry can enrich comprehension over the subjective experience of a disorder, and the utilisation of 'illness narratives' in nursing research have been considered a way of improving knowledge about nursing care and theory development. This research explores experiences of DID through close textual reading and thematic analysis of five biographical and autobiographical texts, discussing the lived experience of the disorder. This narrative approach aims to inform empathetic understanding and support the facilitation of therapeutic alliances in mental healthcare for those experiencing the potentially debilitating and distressing symptoms of DID. Although controversies surrounding the biomedical diagnosis of DID are important to consider, the lived experiences of those who mental health nurses encounter should be priority.

Dissociative identity disorder: validity and use in the criminal justice system

This review examines whether the diagnosis of dissociative identity disorder (DID) could be used to support a defence of ‘not guilty by reason of insanity’ (NGRI, or the insanity defence). The problem is that DID has doubtful validity and can easily be malingered. However, the diagnosis is listed in standard psychiatric manuals. If accepted as valid, DID would have problematic forensic implications.

LEARNING OBJECTIVES

After reading this article you will be able to: •

DECLARATION OF INTEREST

None.

Multiplicity: An Explorative Interview Study on Personal Experiences of People with Multiple Selves

Background and aims: Personality psychology research relies on the notion that humans have a single self that is the result of the individual's thoughts, feelings, and behaviors that can be reliably described (i.e., through traits). People who identify themselves as "multiple" have a system of multiple or alternative, selves, that share the same physical body. This is the first study to explore the phenomenon of multiplicity by assessing the experiences of people who identify themselves as "multiple." Methods: First, an Internet forum search was performed using the terms "multiplicity" and "multiple system." Based on that search, people who identified themselves as multiple were contacted. Interviews were conducted by a consultant psychiatrist, which produced six case vignettes. Results: Multiplicity is discussed on Twitter, Tumblr, Google+ and several other personal websites, blogs, and forums maintained by multiples. According to the study's estimates, there are 200-300 individuals who participate in these forums and believe they are multiple. Based on the six interviews, it appears that multiples have several selves who are relatively independent of each other and constitute the personality's system. Each "resident person" or self, has their own unique behavioral pattern, which is triggered by different situations. However, multiples are a heterogeneous group in terms of their system organization, memory functions, and control over switching between selves. Conclusions: Multiplicity can be placed along a continuum between identity disturbance and dissociative identity disorder (DID), although most systems function relatively well in everyday life. Further research is needed to explore this phenomenon, especially in terms of the extent to which multiplicity can be regarded as a healthy way of coping.

Beyond the Impasse - Reflections on Dissociative Identity Disorder from a Freudian-Lacanian Perspective

Dissociative identity disorder (DID) is a widely contested diagnosis. The dominant posttraumatic model (PTM) considers early life trauma to be the direct cause of the creation of alter identities and assumes that working directly with alter identities should be at the core of the therapeutic work. The socio-cognitive model, on the other hand, questions the validity of the DID diagnosis and proposes an iatrogenic origin of the disorder claiming that reigning therapeutic and socio-cultural discourses create and reify the problem. The author argues that looking at the underlying psychical dynamics can provide a way out of the debate on the veracity of the diagnosis. A structural conception of hysteria is presented to understand clinical and empirical observations on the prevalence, appearance and treatment of DID. On a more fundamental level, the concept of identification and the fundamental division of human psychic functioning are proposed as crucial for understanding the development and treatment of DID.

Trauma-related self-defining memories and future goals in Dissociative Identity Disorder

This study examined the content of self-defining autobiographical memories in different identities in patients with Dissociative Identity Disorder (DID) and comparison groups of patients with PTSD, healthy controls, and DID simulators. Consistent with the DID trauma model, analyses of objective ratings showed that DID patients in trauma identities retrieved more negative and trauma-related self-defining memories than DID patients in avoidant identities. Inconsistent with the DID trauma model, DID patients' self-rated trauma-relatedness of self-defining memories and future life goals did not differ between trauma identities and trauma avoidant identities. That is, the DID patients did not seem to be "shut off" from their trauma while in their avoidant identity. Furthermore, DID patients in both identities reported a higher proportion of avoidance goals compared to PTSD patients, with the latter group scoring comparably to healthy controls. The simulators behaved according to the instructions to respond differently in each identity (i.e., to report memories and goals consistent with the identity tested). The discrepant task behavior by DID patients and simulators indicated that DID patients did not seem to intentionally produce the hypothesized differences in performance between identities. In conclusion, for patients with DID (i.e., in both identities) and patients with PTSD, trauma played a central role in the retrieval of self-defining memories and in the formulation of life goals.

A Proposed Trial of Dialectical Behavior Therapy and Trauma Model Therapy

Dissociative identity disorder and borderline personality disorder resemble each other in trauma histories and comorbidity. Each disorder is frequently comorbid with the other. Treatment outcome data for Dialectical Behavior Therapy of borderline personality disorder and Trauma Model Therapy of dissociative identity disorder are reviewed. The author proposes a psychotherapy treatment study in which there are three subject groups and two treatment conditions. The subject groups are borderline personality disorder without dissociative identity disorder; dissociative identity disorder without borderline personality disorder; and both conditions present concurrently. Subjects would be randomized to receive Dialectical Behavior Therapy or Trauma Model Therapy. Such a study could provide answers to controversies in the field about a better treatment approach for dissociative identity disorder and potentially could broaden and strengthen the indications for Dialectical Behavior Therapy.

Separating Fact from Fiction: An Empirical Examination of Six Myths About Dissociative Identity Disorder

Dissociative identity disorder (DID) is a complex, posttraumatic, developmental disorder for which we now, after four decades of research, have an authoritative research base, but a number of misconceptualizations and myths about the disorder remain, compromising both patient care and research. This article examines the empirical literature pertaining to recurrently expressed beliefs regarding DID: (1) belief that DID is a fad, (2) belief that DID is primarily diagnosed in North America by DID experts who overdiagnose the disorder, (3) belief that DID is rare, (4) belief that DID is an iatrogenic, rather than trauma-based, disorder, (5) belief that DID is the same entity as borderline personality disorder, and (6) belief that DID treatment is harmful to patients. The absence of research to substantiate these beliefs, as well as the existence of a body of research that refutes them, confirms their mythical status. Clinicians who accept these myths as facts are unlikely to carefully assess for dissociation. Accurate diagnoses are critical for appropriate treatment planning. If DID is not targeted in treatment, it does not appear to resolve. The myths we have highlighted may also impede research about DID. The cost of ignorance about DID is high not only for individual patients but for the whole support system in which they reside. Empirically derived knowledge about DID has replaced outdated myths. Vigorous dissemination of the knowledge base about this complex disorder is warranted.

The Psychobiology of Authentic and Simulated Dissociative Personality States: The Full Monty

The etiology of dissociative identity disorder (DID) remains a topic of debate. Proponents of the fantasy model and the trauma model of DID have both called for more empirical research. To this end, the current study presents new and extended data analyses of a previously published H2O positron emission tomography imaging study. This study included 29 subjects: 11 patients with DID and 10 high- and 8 low-fantasy-prone DID-simulating mentally healthy control subjects. All subjects underwent an autobiographical memory script-driven (neutral and trauma related) imagery paradigm in 2 (simulated) dissociative personality states (neutral and trauma related). Psychobiological and psychophysiological data were obtained. Results of the new post-hoc tests on the psychophysiological responses support the trauma model. New results of the brain imaging data did not support the fantasy model. This study extends previously published results by offering important new supporting data for the trauma model of DID.

What Is Constructionism in Psychiatry? From Social Causes to Psychiatric Classification

It is common to note that social environment and cultural formation shape mental disorders. The details of this claim are, however, not well understood. The paper takes a look at the claim that culture has an impact on psychiatry from the perspective of metaphysics and the philosophy of science. Its aim is to offer, in a general fashion, partial explications of some significant versions of the thesis that culture and social environment shape mental disorders and to highlight some of the consequences social constructionism about psychiatry has for psychiatric explanation. In particular, it will be argued that the alleged dependence of facts about particular mental disorders and about the second order property of being a mental disorder on social facts amounts to a robust form of constructivism, whereas the view that clinician-patient interaction is influenced by cultural facts is perfectly compatible with an anti-constructivist stance.

The Classification of Hysteria and Related Disorders: Historical and Phenomenological Considerations

This article examines the history of the conceptualization of dissociative, conversion, and somatoform syndromes in relation to one another, chronicles efforts to classify these and other phenomenologically-related psychopathology in the American diagnostic system for mental disorders, and traces the subsequent divergence in opinions of dissenting sectors on classification of these disorders. This article then considers the extensive phenomenological overlap across these disorders in empirical research, and from this foundation presents a new model for the conceptualization of these disorders. The classification of disorders formerly known as hysteria and phenomenologically-related syndromes has long been contentious and unsettled. Examination of the long history of the conceptual difficulties, which remain inherent in existing classification schemes for these disorders, can help to address the continuing controversy. This review clarifies the need for a major conceptual revision of the current classification of these disorders. A new phenomenologically-based classification scheme for these disorders is proposed that is more compatible with the agnostic and atheoretical approach to diagnosis of mental disorders used by the current classification system.

The horror of stigma: psychosis and mental health care environments in twenty-first-century horror film (part II)

PURPOSE

This paper highlights the specific manner in which twenty-first-century horror films stigmatize psychosis and mental health care environments (MHCEs)

DESIGN AND METHODS

A search on various film forums using the terms "mental/psychiatric patient," "psychosis/psychoses," and "mental/psychiatric hospital" (limited from 2000 to 2012) revealed 55 films. A literature review revealed criteria for a checklist. Subsequent to viewings, salient recurring criteria were added to the checklist. Films were systematically analyzed under these criteria.

FINDINGS

Homicidal maniacs are the most common stereotypes. Misinformation is often communicated. Familiar horror tropes are used to stigmatize MHCEs.

PRACTICE IMPLICATIONS

Practitioners should be aware of the specific manner in which clients are being stigmatized by the media. This paper highlights specific ways in which psychosis and MHCEs are stigmatized, and encourages practitioners to challenge these depictions.

Meet Dr Jekyll: a case of a psychiatrist with dissociative identity disorder

OBJECTIVE

Dissociative identity disorder (DID) is a controversial psychiatric diagnosis. This case review presents a retired psychiatrist with a history of DID.

CONCLUSIONS

This case is used to illustrate current thinking about the characteristics and aetiology of DID. It also argues for the importance of being aware of both our personal and professional biases in our own clinical practice.

Dissociative part-dependent resting-state activity in dissociative identity disorder: a controlled FMRI perfusion study

BACKGROUND

In accordance with the Theory of Structural Dissociation of the Personality (TSDP), studies of dissociative identity disorder (DID) have documented that two prototypical dissociative subsystems of the personality, the "Emotional Part" (EP) and the "Apparently Normal Part" (ANP), have different biopsychosocial reactions to supraliminal and subliminal trauma-related cues and that these reactions cannot be mimicked by fantasy prone healthy controls nor by actors.

METHODS

Arterial spin labeling perfusion MRI was used to test the hypotheses that ANP and EP in DID have different perfusion patterns in response to rest instructions, and that perfusion is different in actors who were instructed to simulate ANP and EP. In a follow-up study, regional cerebral blood flow of DID patients was compared with the activation pattern of healthy non-simulating controls.

RESULTS

Compared to EP, ANP showed elevated perfusion in bilateral thalamus. Compared to ANP, EP had increased perfusion in the dorsomedial prefrontal cortex, primary somatosensory cortex, and motor-related areas. Perfusion patterns for simulated ANP and EP were different. Fitting their reported role-play strategies, the actors activated brain structures involved in visual mental imagery and empathizing feelings. The follow-up study demonstrated elevated perfusion in the left temporal lobe in DID patients, whereas non-simulating healthy controls had increased activity in areas which mediate the mental construction of past and future episodic events.

CONCLUSION

DID involves dissociative part-dependent resting-state differences. Compared to ANP, EP activated brain structures involved in self-referencing and sensorimotor actions more. Actors had different perfusion patterns compared to genuine ANP and EP. Comparisons of neural activity for individuals with DID and non-DID simulating controls suggest that the resting-state features of ANP and EP in DID are not due to imagination. The findings are consistent with TSDP and inconsistent with the idea that DID is caused by suggestion, fantasy proneness, and role-playing.

Differences in trauma history and psychopathology between PTSD patients with and without co-occurring dissociative disorders

BACKGROUND

The interplay between different types of potentially traumatizing events, posttraumatic symptoms, and the pathogenesis of PTSD or major dissociative disorders (DD) has been extensively studied during the last decade. However, the phenomenology and nosological classification of posttraumatic disorders is currently under debate. The current study was conducted to investigate differences between PTSD patients with and without co-occurring major DD with regard to general psychopathology, trauma history, and trauma-specific symptoms.

METHODS

Twenty-four inpatients were administered the Clinician-Administered PTSD Scale for DSM-IV (CAPS) and the Mini-Structured Clinical Interview for DSM-IV Dissociative Disorders (MINI-SKID-D) to assess DD and PTSD. Additionally, participants completed questionnaires to assess general psychopathology and health status.

RESULTS

Symptom profiles and axis I comorbidity were similar in all patients. Traumatic experiences did not differ between the two groups, with both reporting high levels of childhood trauma. Only trauma-specific avoidance behavior and dissociative symptoms differed between groups.

CONCLUSION

Results support the view that PTSD and DD are affiliated disorders that could be classified within the same diagnostic category. Our results accord with a typological model of dissociation in which profound forms of dissociation are specific to DD and are accompanied with higher levels of trauma-specific avoidance in DD patients.

For better or worse: the role of revictimization and stress in the course of treatment for dissociative disorders

Revictimization and life stressors are common among dissociative disorder (DD) patients, yet no studies have examined the prevalence rates for these experiences or their relationships with treatment outcome. This study aimed to examine the rates of revictimization and victimization of others using therapist-DD patient pairs from the naturalistic Treatment of Patients with Dissociative Disorders (TOP DD) study while also considering the role of revictimization and life stressors among 49 patients who greatly improved or worsened during 30 months of treatment. Therapists reported that sexual and physical revictimization in the previous 6 months was high among the patients (3.5%-7.0% and 4.1%-7.1% in the overall TOP DD sample, respectively), and emotional revictimization was quite high (29%-36%). Revictimization showed a decreasing trend over the 30 months of the study. Therapists reported that more than a quarter of the patients who were revictimized were also occasionally emotionally or physically abusive to others. More patients showed sudden improvement versus sudden worsening in patient-reported symptoms at 1 or more time point(s). Patients who improved had significantly fewer revictimizations and stressors overall than patients who worsened, suggesting that revictimization and/or stressors may contribute to worsening in treatment. Further research is needed to learn more about the roles of revictimization, victimization of others, and stressors in DD treatment. [Supplementary material is available for this article. Go to the publisher's online edition of Journal of Trauma & Dissociation for the following supplemental resource: Baseline Demographic Information of TOP DD Improving and Worsening Subgroups].

A review of published research on adult dissociative identity disorder: 2000-2010

The purpose of this study was to assess the scientific and etiological status of dissociative identity disorder (DID) by examining cases published from 2000 to 2010. In terms of scientific status, DID is a small but ongoing field of study. The review yielded 21 case studies and 80 empirical studies, presenting data on 1171 new cases of DID. A mean of 9 articles, each containing a mean of 17 new cases of DID, emerged each year. In terms of etiological status, many of the central criticisms of the disorder's validity remain unaddressed. Most cases of DID emerged from a small number of countries and clinicians. In addition, documented cases occurring outside treatment were almost nonexistent. Finally, people simulating DID in the laboratory were mostly indistinguishable from individuals with DID. Overall, DID is still a topic of study, but the research lacks the productivity and focus needed to resolve ongoing controversies surrounding the disorder.

The rise and fall of dissociative identity disorder

Dissociative identity disorder (DID), once considered rare, was frequently diagnosed during the 1980s and 1990s, after which interest declined. This is the trajectory of a medical fad. DID was based on poorly conceived theories and used potentially damaging treatment methods. The problem continues, given that the DSM-5 includes DID and accords dissociative disorders a separate chapter in its manual.

Fact or factitious? A psychobiological study of authentic and simulated dissociative identity states

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.

The increasing frequency of mania and bipolar disorder: causes and potential negative impacts

The frequency of mania has not changed during the last century even with the development of new diagnostic criteria sets. More specifically, from the mid-1970s to 2000, the rate of mania (variably labeled major affective disorder-bipolar disorder and bipolar I disorder) was consistently identified in US and international studies as ranging from 0.4% to 1.6%. By the late 1990s to the 2000s, the prevalence reported by some researchers for bipolar disorders (I and II and others) was in the 5% to 7% and higher ranges. The purpose of this paper was to review explanations for this change and the potentially negative impacts on the field.

The scientific status of childhood dissociative identity disorder: a review of published research

BACKGROUND

Dissociative identity disorder (DID) remains a controversial diagnosis due to conflicting views on its etiology. Some attribute DID to childhood trauma and others attribute it to iatrogenesis. The purpose of this article is to review the published cases of childhood DID in order to evaluate its scientific status, and to answer research questions related to the etiological models.

METHODS

I searched MEDLINE and PsycINFO records for studies published since 1980 on DID/multiple personality disorder in children. For each study I coded information regarding the origin of samples and diagnostic methods.

RESULTS

The review produced a total of 255 cases of childhood DID reported as individual case studies (44) or aggregated into empirical studies (211). Nearly all cases (93%) emerged from samples of children in treatment, and multiple personalities was the presenting problem in 23% of the case studies. Four US research groups accounted for 65% of all 255 cases. Diagnostic methods typically included clinical evaluation based on Diagnostic and Statistical Manual of Mental Disorder criteria, but hypnosis, structured interviews, and multiple raters were rarely used in diagnoses.

CONCLUSION

Despite continuing research on the related concepts of trauma and dissociation, childhood DID itself appears to be an extremely rare phenomenon that few researchers have studied in depth. Nearly all of the research that does exist on childhood DID is from the 1980s and 1990s and does not resolve the ongoing controversies surrounding the disorder.

Dissociation and Dissociative Disorders

Conventional wisdom holds that dissociation is a coping mechanism triggered by exposure to intense stressors. Drawing on recent research from multiple laboratories, we challenge this prevailing posttraumatic model of dissociation and dissociative disorders. Proponents of this model hold that dissociation and dissociative disorders are associated with (a) intense objective stressors (e.g., childhood trauma), (b) serious cognitive deficits that impede processing of emotionally laden information, and (c) an avoidant information-processing style characterized by a tendency to forget painful memories. We review findings that contradict these widely accepted assumptions and argue that a sociocognitive model better accounts for the extant data. We further propose a perspective on dissociation based on a recently established link between a labile sleep–wake cycle and memory errors, cognitive failures, problems in attentional control, and difficulties in distinguishing fantasy from reality. We conclude that this perspective may help to reconcile the posttraumatic and sociocognitive models of dissociation and dissociative disorders.

[Understanding dissociation in patients with borderline personality disorder]

Dissociation is a disturbing psychiatric concept fraught with controversy. It is however encountered in clinical contexts and has to be understood by clinicians. This article based on a Pubmed/Ovid on line research with key words dissociation and borderline personality disorder and other references, describes the clinical aspects of the dissociative phenomena in patients with borderline personality disorder. Psychodynamic hypotheses and neurophysiological data are examined to explain dissociation. Neurophysiological and neuroanatomical variables provided by cerebral imagery controlled studies support hypotheses brought forward. The article concludes with a defence mechanism developed within a context of biological predisposition, deprived psychological development and in reaction to trauma. In conclusion, emerging psychotherapeutic solutions are summarized.

Childhood abuse and psychosis; a critical review of the literature

Childhood trauma has long been recognised as a potential cause for a range of affective mental health problems arising in adulthood. Only in recent years has the association between childhood abuse and psychosis begun to be investigated. This paper provides a critical review of the literature addressing the relationship between childhood abuse and psychosis. Implications for practitioners are discussed, including practice, policy, treatment and child protection issues. A significant proportion of people develop psychosis in adulthood following all types of childhood abuse, including people diagnosed with schizophrenia, major depressive disorders, dissociative identity disorder and post-traumatic stress disorder. Evidence suggests the possibility of a causal relationship between childhood abuse and psychosis in adulthood. Mental health nurses are ideally placed to offer help, care and support to those individuals who experience psychosis by acknowledging and listening to their life events, including experiences of childhood abuse.

A study of amnesia in homicide cases and forensic psychiatric experts' examination of such claims

About one third of defendants in homicide cases claim amnesia during the time of their alleged act. Examining the authenticity of claimed amnesia is a special challenge for forensic experts. Because the experts' conclusions have legal implications, it is useful to study the characteristics of defendants who claim amnesia regarding a homicidal act and how forensic experts assess these defendants' claims. The forensic psychiatric reports from 2001 to 2007 on 102 Norwegian defendants charged with homicide were assessed quantitatively with a structured rating form. Due to multiple comparisons p of .003 was chosen. Twenty-six defendants claimed partial and 17 claimed total amnesia. No significant differences in the characteristics of the defendants were found between the partial, total, and no amnesia claiming groups. Claims of partial or total amnesia did not change the procedures and content of the forensic experts' examination. A memory test was applied in only one case. Despite the seriousness of the crime and the difficulty of assessing amnesia, the experts did not apply psychological testing of memory function or appropriate tests of possible malingering. Guidelines or standardized procedures for evaluation of defendants who claim amnesia should be developed. This could eventually contribute to more reliable and valid evaluations by forensic experts and increase the probability of just court outcomes.

Errors of logic and scholarship concerning dissociative identity disorder

The author reviewed a two-part critique of dissociative identity disorder published in the Canadian Journal of Psychiatry. The two papers contain errors of logic and scholarship. Contrary to the conclusions in the critique, dissociative identity disorder has established diagnostic reliability and concurrent validity, the trauma histories of affected individuals can be corroborated, and the existing prospective treatment outcome literature demonstrates improvement in individuals receiving psychotherapy for the disorder. The available evidence supports the inclusion of dissociative identity disorder in future editions of the Diagnostic and Statistical Manual of Mental Disorders.

Cross-examining dissociative identity disorder: neuroimaging and etiology on trial

Dissociative identity disorder (DID) is probably the most disputed of psychiatric diagnoses and of psychological forensic evaluations in the legal arena. The iatrogenic proponents assert that DID phenomena originate from psychotherapeutic treatment while traumagenic proponents state that DID develops after severe and chronic childhood trauma. In addition, DID that is simulated with malingering intentions, but not stimulated by psychotherapeutic treatment, may be called pseudogenic. With DID gaining more interest among the general public it can be expected that the number of pseudogenic cases will grow and the need to distinguish between traumagenic, iatrogenic or pseudogenic DID will increase accordingly. This paper discusses whether brain imaging studies can inform the judiciary and/or distinguish the etiology of DID.

A cross-cultural test of the trauma model of dissociation

In order to test the trauma model of dissociation, the authors compared two samples with similar rates of reported childhood physical and sexual abuse: 502 members of the general population in Winnipeg, Canada, and 304 psychiatric outpatients at Shanghai Mental Health Center in Shanghai, China. There is virtually no popular or professional knowledge of dissociative identity disorder in China, and therefore professional and popular contamination cannot be operating. According to the trauma model, samples from different cultures with similar levels of trauma should report similar levels of dissociation. According to the sociocognitive model, in contrast, pathological dissociation is not related to trauma and should be absent in samples free of cultural and professional contamination. Of the 304 Chinese respondents, 14.5% reported childhood physical and/or sexual abuse compared to 12.5% of the Canadian sample. Both samples reported similar levels of dissociation on the Dissociative Experiences Scale and the Dissociative Disorders Interview Schedule. The findings support a specific prediction of the trauma model of dissociation not tested in previous research, and are not consistent with the sociocognitive, contamination or iatrogenic models of dissociative identity disorder.

Psychobiological characteristics of dissociative identity disorder: a symptom provocation study

BACKGROUND

Dissociative identity disorder (DID) patients function as two or more identities or dissociative identity states (DIS), categorized as 'neutral identity states' (NIS) and 'traumatic identity states' (TIS). NIS inhibit access to traumatic memories thereby enabling daily life functioning. TIS have access and responses to these memories. We tested whether these DIS show different psychobiological reactions to trauma-related memory.

METHODS

A symptom provocation paradigm with 11 DID patients was used in a two-by-two factorial design setting. Both NIS and TIS were exposed to a neutral and a trauma-related memory script. Three psychobiological parameters were tested: subjective ratings (emotional and sensori-motor), cardiovascular responses (heart rate, blood pressure, heart rate variability) and regional cerebral blood flow as determined with H(2)(15)O positron emission tomography.

RESULTS

Psychobiological differences were found for the different DIS. Subjective and cardiovascular reactions revealed significant main and interactions effects. Regional cerebral blood flow data revealed different neural networks to be associated with different processing of the neutral and trauma-related memory script by NIS and TIS.

CONCLUSIONS

Patients with DID encompass at least two different DIS. These identities involve different subjective reactions, cardiovascular responses and cerebral activation patterns to a trauma-related memory script.

Becoming one person: living with dissociative identity disorder

Dissociative identity disorder is a rare diagnosis, although people currently with a diagnosis of psychosis may in fact be experiencing what is associated with the disorder. This article is co-authored by a nurse and a person who has lived with alters (multiple personalities) for nearly all of her life. Because of the rarity of the diagnosis, there is much misunderstanding and ignorance among lay people and mental health professionals. This article therefore clarifies historical and contemporary issues surrounding this particular mental health problem both through examining the literature and through narrative of the person's experience. Special attention is given to the reality of coping with the difficulties that dissociative identity disorder create.

Tracking scientific interest in the dissociative disorders: a study of scientific publication output 1984-2003

OBJECTIVE

We attempted to track scientific interest in dissociative amnesia and dissociative identity disorder by estimating the annual output of publications regarding these entities over the last 20 years.

METHODS

Using a standard medical index, PsycINFO, we counted the number of indexed publications involving dissociative amnesia and dissociative identity disorder listed for each year. We then compared these rates with those of well-established diagnoses such as anorexia nervosa, alcohol abuse, and schizophrenia. We also systematically reviewed all publications involving dissociative amnesia that appeared in 2003.

RESULTS

Annual publications involving dissociative amnesia and dissociative identity disorder rose from low levels in the 1980's to a sharp peak in the mid 1990's, followed by an equally sharp decline to only about one quarter of their peak levels by 2002 and 2003. In contrast, all of the 25 comparison diagnoses in our survey showed constant or steadily rising publication rates; none showed the 'bubble' pattern of the dissociative disorders. Of the 34 papers involving dissociative amnesia identified by PsycINFO for 2003, 10 (32%) appeared skeptical of the validity of dissociative amnesia and/or recovered-memory therapy. Despite a detailed search using multiple medical indices and search terms, we could find only 13 explicit cases of individuals with dissociative amnesia worldwide in the 2003 literature.

CONCLUSIONS

Dissociative amnesia and dissociative identity disorder have not generated consistent scientific interest over the years, but instead apparently enjoyed a brief period of fashion that now has waned. Overall, our observations suggest that these diagnostic entities presently do not command widespread scientific acceptance.

Dissociative and conversion disorders: defining boundaries

PURPOSE OF REVIEW

Although dissociative disorders have been described and diagnosed for some time, their aetiology, pathogenesis, phenomenology and management continues to arouse debate. It is only in recent times that researchers have made some progress by integrating trauma related theories with more contemporary cognitive theories and neurobiology.

RECENT FINDINGS

Dissociation as a phenomenon is reported to occur in a variety of disorders. This widespread occurrence has contributed to a better understanding of dissociation. An expansion of this concept may have contributed to the loss of its original significance. Recent studies in the field of dissociation that pertain to its aetiology, pathophysiology, neurobiology and management are critically reviewed.

SUMMARY

Dissociative disorder is conceptually a difficult disorder to study. Apart from exposure to trauma, certain primary personality attributes may contribute to the propensity to develop dissociative disorder. Recent advances in functional neuroimaging facilitated by enhanced knowledge in the neural representation of body state have helped to improve our understanding of dissociation. There is confusion over the use of various terms such as sexual abuse and physical abuse in explaining causality. Current classificatory systems have not been found suitable when applied across cultures. In spite of all of these limitations, there has been recent progress toward a better understanding of dissociative disorders.