Research from 2011

Majohr, K-L., Leenen, K., Grabe, H. J., Jenewein, J., Nuñez, D. G., & Rufer, M., (2011). Alexithymia and its relationship to dissociation in patients with panic disorder. Journal of Nervous and Mental Disease, 199(10), 773-777.

Abstract

Conditions that impede the regulation of emotional arousal, such as alexithymia and dissociation, may underlie panic attacks. This study aimed to evaluate the relationship between alexithymia and dissociation in patients with panic disorder (PD). We assessed 95 PD outpatients with regard to alexithymia (20-item Toronto Alexithymia Scale), dissociation (Dissociation Experi­ence Scale), and overall psychological distress (Symptom Checklist 90-Revised, Global Severity Index). Regression analyses revealed a positive correlation between alexithymia and dissociation, even when the Global Severity Index was controlled for. A specific link was observed between “difficulty in identifying feelings” and “depersonalization/derealization.” Patients who showed the pathological form of dissociation had higher levels of alexithymia, with particular regard to “difficulty in identify­ing feelings” and, to a smaller extent, “difficulty in describing feelings.” These results support a strong relationship between alexithymia and dissociation in patients with PD. Assessing alexithymia and dissociation at the outset of therapy may be helpful for individualized therapy planning.

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Fan, Q., Yu, J., Ross, C. A., Keyes, B. B., Dai, Y., Zhang, T., Wang, L., & Xiao, Z. (2011). Teaching Chinese psychiatrists to make reliable dissociative disorder diagnoses. Transcultural Psychiatry, 48(4), 473-483.

Abstract

The aim of the study was to assess the outcome of an educational effort by two North American experts in dissociative disorders to teach Chinese psychiatrists to make reliable dissociative disorder diagnoses. In the final phase of the educational effort, 569 patients at Shanghai Mental Health Center completed the Chinese version of the Dissociative Experiences Scale (DES). Patients were then randomly selected in different proportions according to their DES scores: 96 selected patients were then assessed with the Dissociative Disorders Interview Schedule (DDIS) and clinical diagnostic interviews based on DSM-IV criteria. According to the clinical diagnostic interviews, 28 (4.9%) patients were diagnosed as having dissociative disorders.

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Chu, J. A. et al. (2011). Guidelines for Treating Dissociative Identity Disorder in Adults, Third Revision: Summary version. Journal of Trauma & Dissociation, 12(2), 188-212.

Abstract

The Guidelines for Treating Dissociative Identity Disorder in Adults presents key findings and generally accepted princi­ples that reflect current scientific knowledge and clinical experience specific to the diagnosis and treatment of dissocia­tive identity disorder (DID) and similar forms of dissociative disorder not otherwise specified (DDNOS). This summary version is intended as a useful synopsis for clinicians; further elaboration of all sections and additional sections, along with academic discussion and references, can be found in the full Guidelines. It should be understood that information in the Guidelines supplements, but does not replace, generally accepted principles of psychotherapy and psychopharma­cology. Treatment for DID should adhere to the basic principles of psychotherapy and psychiatric medical management, and therapists should use specialized techniques only as needed to address specific dissociative symptomatology.

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Schalinski, I., Elbert, T, & Schauer, M. (2011). On the history of dissociative identity disorder in Germany: the doctor Female dissociative responding to extreme sexual violence in a chronic crisis setting: The case of Eastern Congo. Journal of Traumatic Stress, 24(2), 235-238.

Abstract

This cross-sectional study aimed to examine relationships between the number of traumatizing events, degree of shutdown dissociation, posttraumatic stress disorder (PTSD), and depression. Fifty-three female survivors of the ongoing war in Con­go who sought medical treatment were interviewed. A path-analytic model was created with paths to PTSD via dissocia­tion, and both the number of self-experienced and witnessed traumatizing events. Cumulative exposure and dissociation were associated with increased PTSD severity. Posttraumatic stress disorder and witnessing predicted depression when depression was modeled as a consequence of PTSD. Moreover, PTSD mediated the correlation between dissociation and depression. The findings suggest that shutdown dissociation may have value in predicting PTSD, and there is evidence of differential effects of threat to oneself as opposed to witnessing trauma.

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Arnberg, F. K., Eriksson, N-G., Hultman, C. M., Lundin, T. (2011). Traumatic bereavement, acute dissociation, and posttraumatic stress: 14 years after the MS Estonia disaster. Journal of Traumatic Stress, 24(2), 183-190.

Abstract

This prospective longitudinal study aimed to examine posttraumatic stress in survivors 14 years after a ferry disaster, and estimate short- and long-term changes in stress associated with traumatic bereavement and acute dissocia­tion. There were 852 people who perished in the disaster, 137 survived. The 51 Swedish survivors were surveyed with the Impact of Event Scale–Revised (IES-R) at 3 months, 1, 3, and 14 years (response rates 82%, 65%, 51%, and 69%). Symptoms decreased from 3 months to 1 year; no change was found thereafter. After 14 years, 27% reported signifi­cant symptoms. Traumatic bereavement, but not acute dissociation, was associated with long-term symptom elevation. Chronic posttraumatic stress can persist in a minority of survivors, and traumatic bereavement appears to hinder recov­ery.

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Peter, B. (2011). On the history of dissociative identity disorder in Germany: the doctor Justinus Kerner and the girl from Orlach, or possession as an ‘Ex­change of the self’ International Journal of Clinical and Experi­mental Hypnosis, 59, 82-102.

Abstract

The history of hypnosis is closely linked to the theme of possession; one such link is that the forerunner of hypnosis, animal magnetism, replaced exorcism in 1775 when Franz Anton Mesmer testified against Father Johann Joseph Gassner’s exorcism. Modern authors have noted remarkable similarities between states of possession and dissociation. The treatment of possession by animal magnetism and exorcism represents the special romantic–magnetic therapy of the German medical doctor Justinus Kerner in the early 19th century. This article describes the man, his methods, and his thinking and presents one of his most famous case studies, the girl from Orlach, which, by today’s standards, was a true case of dissocia­tive identity disorder (DID). This article describes how contemporary principles of treatment were used and controversial issues about the nature and causes of DID were discussed 175 years ago.

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Rodewald, F., Dell, P. F., Wilhelm-Gößling, C., & Gast, U. (2011). Are major dissociative disorders characterized by a qualitatively different kid of dissociation? Journal of Trauma & Dissociation, 12, 9-24.

Abstract

A total of 66 patients with a major dissociative disorder, 54 patients with non-dissociative disorders, and 30 nonclinical controls were administered the Structured Clinical Interview for DSM–IV Dissociative Disorders–Revised, the Dissociative Experiences Scale, the Multidimensional Inventory of Dissociation, and the Symptom Checklist 90–Revised. Dissociative patients reported significantly more dissociative and non-dissociative symptoms than did non-dissociative patients and nonclinical controls. When general psychopathology was controlled, the dissociation scores of dissociative patients were still significantly higher than those of both other groups, whereas the dissociation scores of non-dissociative patients and nonclinical controls no longer differed. These findings appear to be congruent with a typological model of dissociation that distinguishes between 2 qualitatively different kinds of dissociation. Specifically, the results of this study suggest that the dissociation that occurs in major dissociative disorders (i.e., dis­sociative identity disorder [DID] and dissociative disorder not otherwise specified, Type 1 [DDNOS-1]) is qualitatively different from the dissociation that occurs in persons who do not have a dissociative disor­der. In contrast to previous research, the dissociation of persons who do not have a dissociative disorder is not limited to absorption; it covers a much wider range of phenomena. The authors hypothesize that different mechanisms produce the dissociation of persons with DID and DDNOS-1 as opposed to the dis­sociation of persons who do not have a dissociative disorder.

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Rodewald, F., Wilhelm-Gößling, C., Emrich, H. M., Reddemann, L., & Gast, U. (2011). Axis-I comorbidity in female patients with dissociative identity disorder and dissociative disorder not otherwise specified. Jour­nal of Nervous and Mental Disease, 199, 122-131

Abstract

The aim of this study was to investigate axis-I co-morbidity in patients with dissociative identity disorder (DID) and dissociative disorder not otherwise specified (DDNOS). Using the Diagnostic Interview for Psy­chiatric Disorders, results from patients with DID (n = 44) and DDNOS (n = 22) were compared with those of patients with posttraumatic stress disorder (PTSD) (n = 13), other anxiety disorders (n = 14), depres­sion (n = 17), and nonclinical controls (n = 30). No co-morbid disorders were found in nonclinical controls. The average number of co-morbid disorders in patients with depression or anxiety was 0 to 2. Patients with dissociative disorders averagely suffered from 5 co-morbid disorders. The most prevalent co-morbidity in DDNOS and DID was PTSD. Co-morbidity profiles of patients with DID and DDNOS were very similar to those in PTSD (high prevalence of anxiety, somatoform disorders, and depression), but differed significantly from those of patients with depression and anxiety disorders. These findings confirm the hypothesis that PTSD, DID, and DDNOS are phenomenologically related syndromes that should be summarized within a new diag­nostic category.

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Baars, E. W., Van der Hart, O., Nijenhuis, E. R. S., Chu, J. A., Glas, G., Draijer, N. (2011). Predicting stabilizing treatment outcomes for complex posttrau­matic stress disorder and dissociative identity disorder: An exper­tise-based prognostic model. Journal of Trauma & Dissociation, 12, 67-87.

Abstract

The purpose of this study was to develop an expertise-based prognostic model for the treatment of complex posttraumatic stress disorder (PTSD) and dissociative identity disorder (DID).We developed a survey in 2 rounds: In the first round we surveyed 42 experienced therapists (22 DID and 20 complex PTSD therapists), and in the second round we surveyed a subset of 22 of the 42 therapists (13 DID and 9 complex PTSD therapists). First, we drew on therapists’ knowledge of prognostic factors for stabilization-oriented treatment of complex PTSD and DID. Second, therapists prioritized a list of prognostic factors by estimating the size of each variable’s prognostic effect; we clustered these factors according to content and named the clusters. Next, concept mapping methodology and statistical analyses (including principal components analyses) were used to transform individual judgments into weighted group judgments for clusters of items. A prognostic model, based on consensually determined estimates of effect sizes, of 8 clusters containing 51 factors for both complex PTSD and DID was formed. It includes the clusters lack of motivation, lack of healthy relationships, lack of healthy therapeutic relationships, lack of other internal and external resources, serious Axis I co-morbidity, serious Axis II co-morbidity, poor attachment, and self-destruction. In addition, a set of 5 DID-specific items was constructed. The model is supportive of the current phase-oriented treatment model, emphasizing the strengthening of the therapeutic relation­ship and the patient’s resources in the initial stabilization phase. Further research is needed to test the model’s statistical and clinical validity.

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Van Dijke, A., van der Hart, O., Ford, J. D., van Son, M., van der Heijden, P., & Bühring, M. (2010). Affect dysregulation and dissociation in borderline personality disorder and somatoform disorder: Differentiating inhibitory and excitatory experiencing states. Journal of Trauma & Dissociation, 11(4), 424-443.

Abstract

Affect dysregulation and dissociation may be associated with borderline personality disorder (BPD) and somatoform disorder (SoD). In this study, both under-regulation and over-regulation of affect and positive and negative somatoform and psychoform dissociative experiences were assessed. BPD and SoD diagnoses were confirmed or ruled out in 472 psychiatric inpatients using clinical interviews and clini­cal multidisciplinary consensus. Affect dysregulation and dissociation were measured using self-reports. Under-regulation (but not over-regulation) of affect was moderately related to positive and negative psychoform and somatoform dissociative experiences. Although both BPD and SoD can involve dissocia­tion, there is a wide range of intensity of both somatoform and psychoform dissociative phenomena in patients with these diagnoses. Compared with other groups, SoD patients more often reported low levels of dissociative experiences and reported fewer psychoform (with or without somatoform) dissociative experiences. Compared with the other groups, patients with both BPD and SoD reported more psycho­form (with or without somatoform) dissociative experiences. Evidence was found for the existence of 3 qualitatively different forms of experiencing states. Over-regulation of affect and negative psychoform dissociation, commonly occurring in SoD, can be understood as inhibitory experiencing states. Under-regulation of affect and positive psychoform dissociation, commonly occurring in BPD, can be understood as excitatory experiencing states. The combination of inhibitory and excitatory experiencing states com­monly occurred in comorbid BPD + SoD. Distinguishing inhibitory versus excitatory states of experienc­ing may help to clarify differences in dissociation and affect dysregulation between and within BPD and SoD patients.

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Brown, R. J., Danquah, A. N., Miles, E., Holmes, E., & Poliakoff, E. (2010). Attention to the body in nonclinical somatoform dissociation de­pends on emotional state. Psychosomatic Research, 69, 249-257.

Abstract

Objective: Unexplained neurological symptoms (“somatoform dissociation”) are common in health care settings and associated with disproportionately high levels of distress, disability, and resource utilization. Theory suggests that somatoform dissociation is associated with disturbed attentional processing, but there is a paucity of research in this area and the available evidence is contradictory. Methods: We com­pared undergraduate participants (n = 124) with high and low scores on the Somatoform Dissociation Questionnaire (SDQ-20) on a tactile cueing paradigm measuring the time course of attention to touch, following either a neutral film or a film designed to simulate the emotional effects of trauma exposure. Results: Following the neutral film, high SDQ-20 participants exhibited delayed disengagement from tactile cue stimuli compared to the low SDQ-20 group. Following the “trauma” film, however, the high SDQ-20 group showed attentional effects suggesting avoidance of the tactile stimuli in this condition. Early attention to tactile cues following the trauma film predicted film-related intrusive thoughts after the experiment. Conclusion: These findings suggest that both body vigilance and body avoidance may be involved in the expression of somatoform dissociation.

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Lyttle, N., Dorahy, M. J., Hanna, D., & Huntjens, R. J. C. (2010). Conceptual and perceptual priming and dissociation in chronic posttraumatic stress disorder. Journal of Abnormal Psychology, 119, 777-790.

Abstract

Cognitive models of posttraumatic stress disorder (PTSD) assert that memory processes play a sig­nificant role in PTSD (see e.g., Ehlers & Clark, 2000). Intrusive reexperiencing in PTSD has been linked to perceptual processing of trauma-related material with a corresponding hypothesized lack of concep­tual processing. In an experimental study that included clinical participants with and without PTSD (N = 50), perceptual priming and conceptual priming for trauma-related, general threat, and neutral words were investigated in a population with chronic trauma-induced complaints as a result of the Troubles in Northern Ireland. The study used a new version of the word-stem completion task (Michael, Ehlers, & Halligan, 2005) and a word-cue association task. It also assessed the role of dissociation in threat pro­cessing. Further evidence of enhanced perceptual priming in PTSD for trauma stimuli was found, along with evidence of lack of conceptual priming for such stimuli. Furthermore, this pattern of priming for trauma-related words was associated with PTSD severity, and state dissociation and PTSD group made significant contributions to predicting perceptual priming for trauma words. The findings shed light on the importance of state dissociation in trauma-related information processing and posttraumatic symptoms.

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Perona-Garcelán, S., García-Montes, J. M., Cuevas-Yust, C., Pérez-Álvarez, M., Ductor-Recuerda, M. J., Salas-Azcona, R., & Gómez-Gómez, M. T. (2010). A preliminary exploration of trauma, dissociation, and positive psychotic symptoms in a Spanish sample. Journal of Trauma & Dissociation, 11(3), 284-292.

Abstract

The purpose of this research was to study traumatic and dissociative experiences in a sample of Span­ish psychotic patients. A total of 37 psychotic patients filled out the Dissociative Experiences Scale (E. B. Carlson & F. W. Putnam, 1993), a questionnaire on traumas (J. R. E. Davidson, D. Hughes, & D. G. Blazer, 1990), and the Positive and Negative Syndrome Scale delusion and hallucinations items (S. R. Kay, L. A. Opler, & J. P. Lindenmayer, 1988). The results showed that 40.5% of the subjects in the sample had undergone at least 1 traumatic experience as children and 64.9% had as adults. Patients with hallucina­tions had experienced a higher mean number of childhood traumatic experiences than patients without hallucinations. No significant difference in the mean number of traumatic events was found between patients with and without delusions. There was no significant difference in the mean number of adult­hood traumatic events between patients with and without hallucinations and delusions. Subjects with childhood traumas scored higher on the Dissociative Experiences Scale than those who had had such experiences as adults. Patients with hallucinations and delusions also scored higher on the dissociation scale than patients who did not show those positive psychotic symptoms.

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Terhune, D. B., Cardeña, E., & Lindgren, M. (2010). Dissociated control as a signature of typological variability in high hypnotic suggestibility. Consciousness and Cognition: An International Journal, Dec 11, 2010

Abstract

This study tested the prediction that dissociative tendencies modulate the impact of a hypnotic induc­tion on cognitive control in different subtypes of highly suggestible individuals. Low suggestible (LS), low dissociative highly suggestible (LDHS), and high dissociative highly suggestible (HDHS) participants completed the Stroop color-naming task in control and hypnosis conditions. The magnitude of conflict adaptation (faster response times on incongruent trials preceded by an incongruent trial than those preceded by a congruent trial) was used as a measure of cognitive control. LS and LDHS participants displayed marginally superior up-regulation of cognitive control following a hypnotic induction, whereas HDHS participants’ performance declined. These findings indicate that dissociative tendencies modulate the influence of a hypnotic induction on cognitive control in high hypnotic suggestibility and suggest that HS individuals are comprised of distinct subtypes with dissimilar cognitive profiles.

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Soukup, J., Papežová, H., Kuběna, A.A., Mikolajová, V. (2010). Dissociation in non-clinical and clinical sample of Czech adolescents. Reliability and validity of the Czech version of the adolescent dissociative experiences scale. European Psychiatry, doi:10.1016/j.eurpsy.2010.03.011.

Abstract

Objective: The purpose of this study was to examine psychometric properties of the Czech language version of the Adolescent Dissociative Experiences Scale (A-DES) [2]. METHOD: 653 non-clinical par­ticipants and 162 adolescent psychiatric inpatients completed Czech versions of the A-DES and the Somatoform Dissociation Questionnaire (SDQ-20), and provided further information (data regarding demographic variables, diagnoses, further psychopathology). RESULTS: The Czech A-DES has very good internal consistency, test-retest reliability and a good validity, though its predictive power is limited. The ADES scores significantly correlate with the measure of somatoform dissociation, a presence of clinician-observed dissociative symptoms, reported traumatic experiences, self injurious behavior, and polysymp­tomatic diagnostic picture. A-DES scores were significantly higher in ADHD group, but not in a group with a diagnosis of a dissociative disorder. CONCLUSION: The authors stress that all adolescent psychiatric patients who show more complex behavioral disturbances, have histories of trauma, show self-injurious behaviors or have ADHD diagnosis should be screened for dissociation.

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Somer, E., Altus, L., & Ginzburg, K. (2010). Dissociative psychopathology among opioid use disorder patients: Exploring the ‘chemical dissociation’ hypothesis. Comprehensive Psychiatry, 51(4), 419-425.

Abstract

Background: Although early trauma is a well-recognized risk factor for both dissociation and substance abuse, there are inconsistent reports on the association between substance abuse and dissociation. This inconsistency may be resolved by the “chemical dissociation” hypothesis that suggests that some substance abuse patients may not exhibit high levels of dissociation, despite their trauma history, be­cause they may achieve dissociative-like states through chemicals consumption. This article describes 2 studies aimed to (a) assess the incidence of dissociative psychopathology among recovering opioid use disorder (OUD) patients and (b) examine the chemical dissociation hypothesis. Methods: One hun­dred forty-nine patients receiving treatment in a heroin recovery program and 46 controls were admin­istered self-report measures of dissociation and childhood maltreatment in study 1. A similar battery and an assessment of addiction severity were completed by 50 methadone maintenance treatment (MMT) patients and 30 detoxified OUD patients in study 2. In addition, Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Dissociative Disorders–Revised was administered to a subsample of MMT and detoxified OUD patients. Results: Patients with OUD reported higher levels of child maltreatment and dissociation than controls. Although MMT and detoxi­fied patients did not differ in severity of addiction and child maltreatment, detoxified outpatients had higher levels of dissociation than MMT outpatients: 23% of the detoxified patients and 12% of the MMT patients were diagnosed with a dissociative disorder. Conclusions: These findings support the chemi­cal dissociation hypothesis of OUD and suggest that detoxification programs should take into consid­eration the high incidence of comorbid dissociative disorders among their recovering OUD patients.

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La Mela, C., Maglietta, M., Castellini, G., & Amoroso, L. (2010). Dissociation in eating disorders: Relationship between dissocia­tive experiences and binge-eating episodes. Comprehensive Psychiatry, 51(4), 393-400.

Abstract

Objective: Several findings support the hypothesis that there is a relationship between dissociation and eating disorders (EDs). The aims of this study were as follows: (1) to assess whether ED patients show a higher level of dissociation than healthy control (HC) individuals or psychiatric control patients with anxi­ety and mood disorders and (2) to investigate the effects of dissociation on ED symptoms, specifically binge eating behavior. Method: Fifty-four ED patients, 56 anxiety and mood disorders control patients, and 39 HC individuals completed the Eating Disorder Examination Questionnaire and the Dissociation Questionnaire. Each participant was asked about the number of binge eating episodes he or she had ex­perienced in the past 4 weeks. Results: The ED patients had higher levels of dissociation than both the psychiatric control group and the HC group. In the ED group, the number of binge episodes was related to the level of dissociation. Discussion: Dissociative experiences are relevant in EDs, and binge eating is related to dissociation. In patients affected by the core psychopathologic beliefs of EDs (overevaluation of shape and weight), dissociation may allow an individual to initiate binging behavior, thus decreasing self-awareness and negative emotional states, without having to deal with the long-term consequences of their actions.

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Mueller-Pfeiffer, C., Schumacher, S., Martin-Soelch, C., Pazhenkottil, A. P., Wirtz, G., Fuhrhans, C., Hindermann, E., Assaloni, H., Briner, D. P., Rufer, M. (2010). The validity and reliability of the German version of the Somato­form Dissociation Questionnaire  (SDQ-20). Journal of Trauma & Dissociation, 11(3), 337-357.

Abstract

The present study investigated the validity of the German version of the Somatoform Dissociation Questionnaire (SDQ-20), a scale designed to measure somatoform dissociative symptoms. Somatoform dissociation involves physical manifestations of a dissociation of the personality and is considered a unique entity in the phenomenological spectrum of dissociation. The validity and reliability of the Ger­man version of the SDQ-20 was examined using a sample of 225 patients with (n = 39) and without dis­sociative disorders who were recruited from several in- and outpatient psychiatric clinics. Patients were assessed using structured diagnostic interviews; diagnostic checklists; and self-rating scales for disso­ciation, and posttraumatic stress. Patients with dissociative disorders reported significantly more (p < .001) somatoform dissociative symptoms than patients without dissociative disorders (criterion validity). Significant correlations (p < .001) were found between scores of somatoform dissociation, psycho-form dissociation, posttraumatic stress symptoms, and traumatic childhood experiences (construct validity). Reliability was corroborated by a Cronbach’s alpha coefficient of .91 and a test–retest correlation of .89. A component factor analysis suggested unidi-mensionality of the SDQ-20. In conclusion, the psychomet­ric properties and cross-cultural validity of the German version of the SDQ-20 are excellent. Our results form the basis for the further study of somatoform dissociation in German-speaking populations.

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Espirito-Santo, H., Pio-Abreu, J. L. (2009). Psychiatric symptoms and dissociation in conversion, somatiza­tion and dissociative disorders. Australian and New Zealand Journal of Psychiatry, 43(3), 270-276.

Abstract

Objective: Conversion, dissociation and somatization are historically related in the long established con­cept of hysteria. Somewhere along the way they were separated due to the Cartesian dualistic view. The aim of the present study was to compare these pathologies and investigate whether symptoms of these pathologies overlap in their clinical appearance in a Portuguese sample. Method: Twenty-six patients with conversion disorder, 38 with dissociative disorders, 40 with somatization disorder, and a comparison group of 46 patients having other psychiatric disorders answered questions about dissociation (Dissocia­tive Experiences Scale), somatoform dissociation (Somatoform Dissociation Questionnaire), and psy­chopathological symptoms (Brief Symptom Inventory). Results: Dissociative and somatoform symptoms were significantly more frequent in dissociative and conversion disorder than in somatization disorder and controls. There were no significant differences between dissociative and conversion patients. Conclu­sions: Conversion disorder is closely related to dissociative disorders. These results support the ICD-10 categorization of conversion disorder among dissociative disorders and the hypothesis of analogous psy­chopathological processes in conversion and dissociative disorders versus somatization disorder.

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Dale, K. Y., Berg, R., Elden, Å., Ødegård, A., Holte, A. (2009). Testing the diagnosis of dissociative identity disorder through measures of dissociation, absorption, hypnotizability and PTSD: A Norwegian pilot study. Journal of Trauma & Dissociation, 10(1), 102-112.

Abstract

A total of 14 women meeting criteria for dissociative identity disorder (DID) based on the Diagnostic and Statistical Manual of Mental Disorders (4th ed. [DSM–IV]) were compared to a group of women (n = 10) with other dissociative diagnoses and a group of normal controls (n = 14) with regard to dissociativity, absorption, trauma related symptoms and hypnotizability. Both of the clinical groups reported histories of childhood trauma and attained high PTSD scores. The DID group differed significantly from the group with other dissociative diagnoses and the non-diagnosed comparison group with regard to hypnotiz­ability, the variety of dissociative symptomatology, and the magnitude of dissociative symptomatology. However, no significant differences between the two clinical groups were detected with regard to absorp­tion, general dissociative level, or symptoms related to traumatic stress. Results support the notion that DID can be regarded as a clinical entity which is separable from other dissociative disorders. Results also indicated that hypnotizability is the most important clinical feature of DID.