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Lanfranco RC, Martínez-Aguayo JC, Arancibia M. Assessing malingering and personality styles in dissociative identity disorder: a case study. Neurocase 2023; 29:141-150. [PMID: 38704614 DOI: 10.1080/13554794.2024.2348218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 04/15/2024] [Indexed: 05/06/2024]
Abstract
Dissociative Identity Disorder (DID), formerly Multiple Personality Disorder, involves two or more distinct identities controlling behaviour, stemming from trauma-related dissociation. Understanding DID's cognitive, neural, and psychometric aspects remains a challenge, especially in distinguishing genuine cases from malingering. We present a case of a DID patient with nine identities, evaluated to rule out malingering. Using the Millon Index of Personality Styles, we assessed the primary and two alternate identities, revealing marked differences. High consistency scores support validity. We suggest employing personality inventories beyond symptomatology to characterise dissociative identities' consistency and adaptation styles, aiding in malingering assessments in future studies.
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Affiliation(s)
- Renzo C Lanfranco
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
- Department of Psychology, University of Edinburgh, Edinburgh, UK
- Center for Research in Cognition & Neurosciences, Université libre de Bruxelles, Brussels, Belgium
| | | | - Marcelo Arancibia
- Center of Translational Studies in Stress and Mental Health (C-ESTRES), Faculty of Sciences, Universidad de Valparaíso, Valparaíso, Chile
- Department of Psychiatry, School of Medicine, Faculty of Medicine, Universidad de Valparaíso, Valparaíso, Chile
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Marsh RJ, Dorahy MJ, Butler C, Middleton W, de Jong PJ, Kemp S, Huntjens R. Inter-identity amnesia for neutral episodic self-referential and autobiographical memory in Dissociative Identity Disorder: An assessment of recall and recognition. PLoS One 2021; 16:e0245849. [PMID: 33577556 PMCID: PMC7880432 DOI: 10.1371/journal.pone.0245849] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 01/09/2021] [Indexed: 11/18/2022] Open
Abstract
Amnesia is a core diagnostic criterion for Dissociative Identity Disorder (DID), however previous research has indicated memory transfer. As DID has been conceptualised as being a disorder of distinct identities, in this experiment, behavioral tasks were used to assess the nature of amnesia for episodic 1) self-referential and 2) autobiographical memories across identities. Nineteen DID participants, 16 DID simulators, 21 partial information, and 20 full information comparison participants from the general population were recruited. In the first study, participants were presented with two vignettes (DID and simulator participants received one in each of two identities) and asked to imagine themselves in the situations outlined. The second study used a similar methodology but with tasks assessing autobiographical experience. Subjectively, all DID participants reported amnesia for events that occurred in the other identity. On free recall and recognition tasks they presented a memory profile of amnesia similar to simulators instructed to feign amnesia and partial information comparisons. Yet, on tests of recognition, DID participants recognized significantly more of the event that occurred in another identity than simulator and partial information comparisons. As such, results indicate that the DID performance profile was not accounted for by true or feigned amnesia, lending support to the idea that reported amnesia may be more of a perceived than actual memory impairment.
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Affiliation(s)
- Rosemary J. Marsh
- School of Psychology, Speech and Hearing, University of Canterbury, Canterbury, New Zealand
- Department of Clinical Psychology, University of Groningen, Groningen, Netherlands
| | - Martin J. Dorahy
- School of Psychology, Speech and Hearing, University of Canterbury, Canterbury, New Zealand
- The Cannan Institute, Belmont Private Hospital, Brisbane, Australia
- * E-mail:
| | - Chandele Butler
- School of Psychology, Speech and Hearing, University of Canterbury, Canterbury, New Zealand
| | - Warwick Middleton
- School of Psychology, Speech and Hearing, University of Canterbury, Canterbury, New Zealand
- The Cannan Institute, Belmont Private Hospital, Brisbane, Australia
| | - Peter J. de Jong
- Department of Clinical Psychology, University of Groningen, Groningen, Netherlands
| | - Simon Kemp
- School of Psychology, Speech and Hearing, University of Canterbury, Canterbury, New Zealand
| | - Rafaele Huntjens
- Department of Clinical Psychology, University of Groningen, Groningen, Netherlands
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Riaz M, Hashmi MR. m-polar neutrosophic soft mapping with application to multiple personality disorder and its associated mental disorders. Artif Intell Rev 2020. [DOI: 10.1007/s10462-020-09912-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Gandotra K, Golish J, Rosenberg C, Strohl K. Dissociative Identity Disorder CPAP Adherence: An Uncommon Factor in Obstructive Sleep Apnea. J Clin Sleep Med 2018; 14:693-695. [PMID: 29609713 DOI: 10.5664/jcsm.7076] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Accepted: 11/30/2017] [Indexed: 11/13/2022]
Abstract
ABSTRACT We present a case of a patient with dissociative identity disorder and symptomatic sleep apnea who was treated with continuous positive airway pressure (CPAP). CPAP use depended upon which personality the patient exhibited but apnea reduction did not. This case illustrates in one individual how personality can positively or negatively affect CPAP adherence.
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Affiliation(s)
- Kamal Gandotra
- Division of Pulmonary and Sleep Medicine, Louis Stokes VA Medical Center, Cleveland, Ohio
| | - Joseph Golish
- Division of Pulmonary, Critical Care and Sleep Medicine, Metro Health Medical Center, Case Western Reserve University, Cleveland, Ohio
| | - Carl Rosenberg
- Division of Pulmonary and Sleep Medicine, Louis Stokes VA Medical Center, Cleveland, Ohio
| | - Kingman Strohl
- Division of Pulmonary and Sleep Medicine, Louis Stokes VA Medical Center, Cleveland, Ohio.,Division of Pulmonary, Critical Care and Sleep Medicine, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, Ohio
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Abstract
INTRODUCTION Patients diagnosed with dissociative identity disorder (DID) usually present with alternative personality states (alters) who take separate control of consciousness. Commonly, one alter will claim they have no awareness of events which took place when another alter was in control. However, some kinds of material are transferred across the alter boundary. Huntjens et al. devised an objective method of demonstrating such transfer. METHODS In the main study, following Huntjens et al., for three patients, two alters were taught different sets of nouns. The following week, one of the alters was given a recognition memory test including both sets plus distractor words. The patients in the Huntjens experiment responded in the same way to words in both sets. RESULTS In the present experiemnt, two of the patients tested had pairs of alters where there was no interference from the material which was presented to the other alter. In one of these cases, there was breakthrough with one pairing of alters, a pattern matched in a subsidiary experiment. CONCLUSIONS The population of individuals with DID are not homogeneous with respect to the depth of the blocking of episodic material from one alter to another.
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Affiliation(s)
- John Morton
- a Institute of Cognitive Neuroscience, University College , London , UK
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6
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Abstract
Two groups of college students were selected on the basis of their scores on the Dissociative Experiences Scale (DES). The high-DES group (score > 20, M = 29.6; n = 54) and low-DES group (score < 10, M = 5.1; n = 54) both completed the standard and a new dualtask version of the Stroop ink-naming task with xs (baseline condition) and color, neutral, and emotionally charged words. Free recall results indicated that high-DES participants remembered fewer emotionally charged words than low-DES participants. We found a crossover interaction for Stroop interference: High-DES participants showed more interference (conflicting color – baseline latency for ink naming) in a selective-attention Stroop task and less interference in the dualtask Stroop task. The interaction between attentional context and dissociation for Stroop interference and the free recall results are consistent with a cognitive-environments view of dissociative tendencies. In this view, dissociative tendencies, which have been otherwise speculated to be largely deleterious, can be advantageous in certain contexts.
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Abstract
Virtually all patients with dissociative identity (or multiple personality) disorder manifest interpersonality amnesia, whereby events experienced by a particular personality state or identity are retrievable by that same identity but not by a different one Though considered a hallmark of dissociative identity disorder (DID), interpersonality amnesia has to date attracted little empirical attention. Further, the few studies on the topic typically include just 1 DID patient and a single index of retention In contrast the current experiment involved 9 DID patients and several measures of either explicit or implicit memory Replicating and extending the single-case study of Nissen, Ross, Willingham, MacKenzie, and Schacter (1988), the present results revealed that implicit testing is a necessary but not a sufficient condition for demonstrating transfer of information from one identity to another Specifically, whereas priming in word-stem completion occurred only if the same personality state performed at both study and at test, priming in picture-fragment completion was as robust between different identities as it was within the same identity Discussion focuses on prospects for future research aimed at understanding the nature and scope of interpersonality amnesia
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Dorahy MJ, Brand BL, Sar V, Krüger C, Stavropoulos P, Martínez-Taboas A, Lewis-Fernández R, Middleton W. Dissociative identity disorder: An empirical overview. Aust N Z J Psychiatry 2014; 48:402-17. [PMID: 24788904 DOI: 10.1177/0004867414527523] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
OBJECTIVE Despite its long and auspicious place in the history of psychiatry, dissociative identity disorder (DID) has been associated with controversy. This paper aims to examine the empirical data related to DID and outline the contextual challenges to its scientific investigation. METHODS The overview is limited to DID-specific research in which one or more of the following conditions are met: (i) a sample of participants with DID was systematically investigated, (ii) psychometrically-sound measures were utilised, (iii) comparisons were made with other samples, (iv) DID was differentiated from other disorders, including other dissociative disorders, (v) extraneous variables were controlled or (vi) DID diagnosis was confirmed. Following an examination of challenges to research, data are organised around the validity and phenomenology of DID, its aetiology and epidemiology, the neurobiological and cognitive correlates of the disorder, and finally its treatment. RESULTS DID was found to be a complex yet valid disorder across a range of markers. It can be accurately discriminated from other disorders, especially when structured diagnostic interviews assess identity alterations and amnesia. DID is aetiologically associated with a complex combination of developmental and cultural factors, including severe childhood relational trauma. The prevalence of DID appears highest in emergency psychiatric settings and affects approximately 1% of the general population. Psychobiological studies are beginning to identify clear correlates of DID associated with diverse brain areas and cognitive functions. They are also providing an understanding of the potential metacognitive origins of amnesia. Phase-oriented empirically-guided treatments are emerging for DID. CONCLUSIONS The empirical literature on DID is accumulating, although some areas remain under-investigated. Existing data show DID as a complex, valid and not uncommon disorder, associated with developmental and cultural variables, that is amenable to psychotherapeutic intervention.
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Affiliation(s)
- Martin J Dorahy
- 1Department of Psychology, University of Canterbury, Christchurch, New Zealand
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Barlow MR, Chu JA. Measuring fragmentation in dissociative identity disorder: the integration measure and relationship to switching and time in therapy. Eur J Psychotraumatol 2014; 5:22250. [PMID: 24396569 PMCID: PMC3880957 DOI: 10.3402/ejpt.v5.22250] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Revised: 10/20/2013] [Accepted: 11/20/2013] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Some people with dissociative identity disorder (DID) have very little communication or awareness among the parts of their identity, while others experience a great deal of cooperation among alternate identities. Previous research on this topic has been sparse. Currently, there is no empirical measure of integration versus fragmentation in a person with DID. In this study, we report the development of such a measure. OBJECTIVE The goal of this study was to pilot the integration measure (IM) and to address its psychometric properties and relationships to other measures. The IM is the first standardized measure of integration in DID. METHOD Eleven women with DID participated in an experiment that included a variety of tasks. They filled out questionnaires about trauma and dissociation as well as the IM. They also provided verbal results about switching among alternate identities during the study sessions. RESULTS Participants switched among identities an average of 5.8 times during the first session, and switching was highly correlated with trauma. Integration was related to switching, though this relationship may be non-linear. Integration was not related to time in psychotherapy. CONCLUSIONS The IM provides a useful beginning to quantify and study integration and fragmentation in DID. Directions for future research are also discussed, including expanding the IM from this pilot. The IM may be useful in treatment settings to assess progress or change over time.
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Affiliation(s)
- M Rose Barlow
- Psychology Department, Boise State University, Boise, ID, USA
| | - James A Chu
- McLean Hospital, Belmont, MA, USA ; Harvard Medical School, Department of Psychiatry, Boston, MA, USA
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10
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Inter-identity autobiographical amnesia in patients with dissociative identity disorder. PLoS One 2012; 7:e40580. [PMID: 22815769 PMCID: PMC3399886 DOI: 10.1371/journal.pone.0040580] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 06/11/2012] [Indexed: 12/05/2022] Open
Abstract
Background A major symptom of Dissociative Identity Disorder (DID; formerly Multiple Personality Disorder) is dissociative amnesia, the inability to recall important personal information. Only two case studies have directly addressed autobiographical memory in DID. Both provided evidence suggestive of dissociative amnesia. The aim of the current study was to objectively assess transfer of autobiographical information between identities in a larger sample of DID patients. Methods Using a concealed information task, we assessed recognition of autobiographical details in an amnesic identity. Eleven DID patients, 27 normal controls, and 23 controls simulating DID participated. Controls and simulators were matched to patients on age, education level, and type of autobiographical memory tested. Findings Although patients subjectively reported amnesia for the autobiographical details included in the task, the results indicated transfer of information between identities. Conclusion The results call for a revision of the DID definition. The amnesia criterion should be modified to emphasize its subjective nature.
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11
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Klein SB, Lax ML. The unanticipated resilience of trait self-knowledge in the face of neural damage. Memory 2010; 18:918-48. [DOI: 10.1080/09658211.2010.524651] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Abstract
The dissociative disorders, including "psychogenic" or "functional" amnesia, fugue, dissociative identity disorder (DID, also known as multiple personality disorder), and depersonalization disorder, were once classified, along with conversion disorder, as forms of hysteria. The 1970s witnessed an "epidemic" of dissociative disorder, particularly DID, which may have reflected enthusiasm for the diagnosis more than its actual prevalence. Traditionally, the dissociative disorders have been attributed to trauma and other psychological stress, but the existing evidence favoring this hypothesis is plagued by poor methodology. Prospective studies of traumatized individuals reveal no convincing cases of amnesia not attributable to brain insult, injury, or disease. Treatment generally involves recovering and working through ostensibly repressed or dissociated memories of trauma; at present, there are few quantitative or controlled outcome studies. Experimental studies are few in number and have focused largely on state-dependent and implicit memory. Depersonalization disorder may be in line for the next "epidemic" of dissociation.
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Affiliation(s)
- John F Kihlstrom
- Department of Psychology, University of California, Berkeley, California 94720-1650, USA.
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Huntjens RJC, Peters ML, Woertman L, van der Hart O, Postma A. Memory transfer for emotionally valenced words between identities in dissociative identity disorder. Behav Res Ther 2007; 45:775-89. [PMID: 16928360 DOI: 10.1016/j.brat.2006.07.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2005] [Revised: 06/22/2006] [Accepted: 07/03/2006] [Indexed: 10/24/2022]
Abstract
The present study aimed to determine interidentity retrieval of emotionally valenced words in dissociative identity disorder (DID). Twenty-two DID patients participated together with 25 normal controls and 25 controls instructed to simulate DID. Two wordlists A and B were constructed including neutral, positive and negative material. List A was shown to one identity, while list B was shown to another identity claiming total amnesia for the words learned by the first identity. The identity claiming amnesia was tested for intrusions from list A words into the recall of words from list B and recognition of the words learned by both identities. Test results indicated no evidence of total interidentity amnesia for emotionally valenced material in DID. It is argued that dissociative amnesia in DID may more adequately be described as a disturbance in meta-memory functioning instead of an actual retrieval inability.
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Affiliation(s)
- Rafaële J C Huntjens
- University of Groningen, Department of Developmental and Clinical Psychology, Groningen, The Netherlands.
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15
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Barlow MR. Researching dissociative identity disorder: practical suggestions and ethical implications. J Trauma Dissociation 2007; 8:81-96. [PMID: 17409056 DOI: 10.1300/j229v08n01_06] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This article's purpose is to aid researchers who are interested in conducting research with dissociative populations, but who may not have extensive experience in this area. Researching dissociative identity disorder (DID) comes with many challenges. In this article, the ethics and logistics involved in selecting and implementing research methodology with DID samples are considered. This advice is centered in the author's experience of conducting research with adults in North American hospital and community settings. Researchers in this area should design data collection procedures for maximum flexibility and participant comfort, while maintaining an acceptable level of scientific rigor. Training is essential so that both principal investigators and assistants are able to deal sensitively with trauma survivors. Psychology researchers have a unique ability to be aware of hierarchy and power in the experimental setting, and to consider these issues in order to convey respect for participants.
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Affiliation(s)
- M Rose Barlow
- Department of Psychology, University of Oregon, USA.
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Dorahy MJ, McCusker CG, Loewenstein RJ, Colbert K, Mulholland C. Cognitive inhibition and interference in dissociative identity disorder: The effects of anxiety on specific executive functions. Behav Res Ther 2006; 44:749-64. [PMID: 16087154 DOI: 10.1016/j.brat.2005.05.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2004] [Revised: 04/18/2005] [Accepted: 05/16/2005] [Indexed: 10/25/2022]
Abstract
Using an experimentally based, computer-presented task, this study assessed cognitive inhibition and interference in individuals from the dissociative identity disorder (DID; n=12), generalized anxiety disorder (GAD; n=12) and non-clinical (n=12) populations. Participants were assessed in a neutral and emotionally negative (anxiety provoking) context, manipulated by experimental instructions and word stimuli. The DID sample displayed effective cognitive inhibition in the neutral but not the anxious context. The GAD sample displayed the opposite findings. However, the interaction between group and context failed to reach significance. There was no indication of an attentional bias to non-schema specific negative words in any sample. Results are discussed in terms of the potential benefit of weakened cognitive inhibition during anxious arousal in dissociative individuals.
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Affiliation(s)
- Martin J Dorahy
- Trauma Resource Centre, North and West Belfast HSS Trust, Northern Ireland; School of Psychology, The Queen's University of Belfast, Northern Ireland.
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Huntjens RJC, Postma A, Woertman L, van der Hart O, Peters ML. Procedural memory in dissociative identity disorder: When can inter-identity amnesia be truly established? Conscious Cogn 2005; 14:377-89. [PMID: 15950888 DOI: 10.1016/j.concog.2004.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2003] [Revised: 01/21/2004] [Accepted: 10/04/2004] [Indexed: 10/26/2022]
Abstract
In a serial reaction time task, procedural memory was examined in Dissociative Identity Disorder (DID). Thirty-one DID patients were tested for inter-identity transfer of procedural learning and their memory performance was compared with 25 normal controls and 25 controls instructed to simulate DID. Results of patients seemed to indicate a pattern of inter-identity amnesia. Simulators, however, were able to mimic a pattern of inter-identity amnesia, rendering the results of patients impossible to interpret as either a pattern of amnesia or a pattern of simulation. It is argued that studies not including DID-simulators or simulation-free memory tasks, should not be taken as evidence for (or against) amnesia in DID.
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Affiliation(s)
- Rafaële J C Huntjens
- Department of Clinical Psychology, Research Institute for Psychology and Health, Faculty of Social Sciences, Utrecht University, P.O. Box 80.140, 3508 TC, Utrecht, The Netherlands.
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Huntjens RJC, Peters ML, Postma A, Woertman L, Effting M, van der Hart O. Transfer of newly acquired stimulus valence between identities in dissociative identity disorder (DID). Behav Res Ther 2005; 43:243-55. [PMID: 15629753 DOI: 10.1016/j.brat.2004.01.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2003] [Revised: 12/22/2003] [Accepted: 01/20/2004] [Indexed: 11/15/2022]
Abstract
Patients with Dissociative Identity Disorder (DID) frequently report episodes of interidentity amnesia, that is amnesia for events experienced by other identities. The goal of the present experiment was to test the implicit transfer of trauma-related information between identities in DID. We hypothesized that whereas declarative information may transfer from one identity to another, the emotional connotation of the memory may be dissociated, especially in the case of negative, trauma-related emotional valence. An evaluative conditioning procedure was combined with an affective priming procedure, both performed by different identities. In the evaluative conditioning procedure, previously neutral stimuli come to refer to a negative or positive connotation. The affective priming procedure was used to test the transfer of this acquired valence to an identity reporting interidentity amnesia. Results indicated activation of stimulus valence in the affective priming task, that is transfer of emotional material between identities.
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Affiliation(s)
- Rafaële J C Huntjens
- Department of Clinical Psychology, Faculty of Social Sciences, Utrecht University, P.O. Box 80.140, Utrecht 3508 TC, The Netherlands.
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Abstract
We start by assuming that the self is implemented in the brain as a functional unit, with a definite set of properties. We deduce the fundamental properties of the self from an analysis of neurological disorders and from introspection. We formulate a functionalist concept of the self based on these properties reduced to constraints. We use the formalism of schemas in our functionalist analysis, i.e. a symbolic level description of brain dynamics. We then reformulate the functionalist model at a connectionist level and address the emergent "context shifting" problem. We suggest how the model might be mapped onto the functional neuroanatomy of the brain, and how it could be used to give an account of a range of neurological disorders, including hippocampal amnesia, various forms of schizophrenia, multiple personality, autism, PTSD, hemineglect, and reversible anosognosia. Finally, we briefly discuss future perspectives and possible applications of computer implementations of the model.
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Affiliation(s)
- Alexei V Samsonovich
- Krasnow Institute for Advanced Study, George Mason University, Fairfax, VA 22030-4444, USA.
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20
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Dorahy MJ, Irwin HJ, Middleton W. Assessing markers of working memory function in dissociative identity disorder using neutral stimuli: a comparison with clinical and general population samples. Aust N Z J Psychiatry 2004; 38:47-55. [PMID: 14731194 DOI: 10.1177/000486740403800101] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVES Memory functioning is a central conceptual and phenomenological aspect of dissociative identity disorder (DID). Most empirical work on memory functions in DID has focused on retrieval deficits either within or between dissociated identities. The current study attempted to remedy the scant attention given to working memory functioning. METHOD In samples representing the DID, non-clinical, depressed, posttraumatic stress disorder (PTSD) and psychosis populations (n = 10 per group), neutral stimuli were used to examine three markers of working memory functioning: one measuring inhibition; one assessing facilitation; and one measuring interference. RESULTS With the exception of the psychosis sample all groups displayed significant negative priming in the distractor inhibition condition. Facilitation effects were demonstrated by the DID and PTSD groups only. Interference effects were evident in all samples, though the DID and non-clinical groups demonstrated significantly more interference than the psychosis cohort. Distractor inhibition was related to overall schizotypy scores, and dissociation was related to scores in the facilitation condition. CONCLUSIONS The DID sample displayed a completely distinct functional working memory profile to the psychosis sample when assessed with emotionally neutral stimuli. However, the working memory profile in the DID sample was not entirely dissimilar to the other comparison groups.
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Affiliation(s)
- Martin J Dorahy
- Psychologist, Clinical Psychology Program, School of Psychology, Queens University, David Keir Building, Malone Road, Belfast, BT9 5BP, Northern Ireland.
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Huntjens RJC, Postma A, Peters ML, Woertman L, van der Hart O. Interidentity amnesia for neutral, episodic information in dissociative identity disorder. JOURNAL OF ABNORMAL PSYCHOLOGY 2003; 112:290-7. [PMID: 12784839 DOI: 10.1037/0021-843x.112.2.290] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Interidentity amnesia is considered a hallmark of dissociative identity disorder (DID) in clinical practice. In this study, objective methods of testing episodic memory transfer between identities were used. Tests of both recall (interference paradigm) and recognition were used. A sample of 31 DID patients was included. Additionally, 50 control subjects participated, half functioning as normal controls and the other half simulating interidentity amnesia. Twenty-one patients subjectively reported complete one-way amnesia for the learning episode. However, objectively, neither recall nor recognition scores of patients were different from those of normal controls. It is suggested that clinical models of amnesia in DID may be specified to exclude episodic memory impairments for emotionally neutral material.
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Affiliation(s)
- Rafaële J C Huntjens
- Department of Clinical Psychology and Reseach Institute for Psychology and Health, Utrecht University, The Netherlands.
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22
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Elzinga BM, Phaf RH, Ardon AM, van Dyck R. Directed forgetting between, but not within, dissociative personality states. JOURNAL OF ABNORMAL PSYCHOLOGY 2003; 112:237-43. [PMID: 12784833 DOI: 10.1037/0021-843x.112.2.237] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
To investigate amnesia between identities in dissociative identity disorder (DID), the authors assessed explicit and implicit memory performance on a directed-forgetting task in 12 DID patients who switched from one state to an "amnesic" state between presentation and memory testing. DID patients were instructed either to remember or to forget neutral and emotional words. Besides an overall decrease in explicit memory, patients demonstrated selective forgetting of to-be-forgotten, but not of to-be-remembered words in the amnesic state. Patients did not exhibit any directed forgetting within the same state. Implicit memory was fully preserved across states. Independent of state, patients recalled more emotional than neutral information. These results may extend the conceptualization of memory processes in DID, suggesting an important role for retrieval inhibition.
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Affiliation(s)
- Bernet M Elzinga
- Section of Clinical and Health Psychology, University of Leiden, The Netherlands.
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Huntjens RJC, Postma A, Hamaker EL, Woertman L, van der Hart O, Peters M. Perceptual and conceptual priming in patients with dissociative identity disorder. Mem Cognit 2002; 30:1033-43. [PMID: 12507368 DOI: 10.3758/bf03194321] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The present study examined implicit memory transfer in patients with dissociative identity disorder (DID). To determine priming impairments in DID, we included both several perceptual priming tasks and a conceptual priming task using neutral material. We tested a large sample of DID patients (n = 31), in addition to 25 controls and 25 DID simulators, comparable on sex, age, and education. Controls replicated conceptual priming results of Vriezen, Moscovitch, and Bellos (1995) by showing that conceptual priming seems to require the formation of domain-specific semantic representations, denoting either sensory or functional object attributes. We extended a study performed by Schacter, Cooper, and Delaney (1990) by demonstrating priming for impossible object using the sensitive priming index of response times. The simulators in the study were not able to simulate interidentity amnesia on the implicit memory tasks employed. Partly in contrast to participants in previous studies, DID patients showed evidence of perceptual priming as well as conceptual priming comparable to that of controls. DID patients thus displayed normal implicit memory performance.
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Affiliation(s)
- Rafaële J C Huntjens
- Department of Clinical Psychology, Faculty of Social Sciences, Utrecht University, Utrecht, The Netherlands.
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Lucchelli F, Spinnler H. The "psychogenic" versus "organic" conundrum of pure retrograde amnesia: is it still worth pursuing? Cortex 2002; 38:665-9. [PMID: 12465679 DOI: 10.1016/s0010-9452(08)70033-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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25
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Merckelbach H, Devilly GJ, Rassin E. Alters in dissociative identity disorder. Metaphors or genuine entities? Clin Psychol Rev 2002; 22:481-97. [PMID: 12094508 DOI: 10.1016/s0272-7358(01)00115-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
How should the different identities (i.e., alters) that are thought to be typical for dissociative identity disorder (DID) be interpreted? Are they just metaphors for different emotional states or are they truly autonomous entities that are capable of willful action? This issue is important because it has implications for the way in which courts may handle cases that involve DID patients. Referring to studies demonstrating that alters of DID patients differ in their memory performance or physiological profile, some authors have concluded that alters are more than just metaphors. We argue that such line of reasoning is highly problematic. There is little consensus among authors about the degree to which various types of memory information (implicit, explicit, procedural) may leak from one to the other alter. Without such theoretical accord, any given outcome of memory studies on DID may be taken as support for the assumption that alters are in some sense "real." As physiological studies on alter activity often lack proper control conditions, most of them are inconclusive as to the status of alters. To date, neither memory studies nor psychobiological studies have delivered compelling evidence that alters of DID patients exist in a factual sense. As a matter of fact, results of these studies are open to multiple interpretations and in no way refute an interpretation of alters in terms of metaphors for different emotional states.
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Affiliation(s)
- Harald Merckelbach
- Department of Experimental Psychology, Faculty of Law, University of Maastricht, P.O. Box 616, 6200 MD, Maastricht, The Netherlands.
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Forrest KA. Toward an etiology of dissociative identity disorder: a neurodevelopmental approach. Conscious Cogn 2001; 10:259-93. [PMID: 11697866 DOI: 10.1006/ccog.2001.0493] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This article elaborates on Putnam's "discrete behavioral states" model of dissociative identity disorder (Putnam, 1997) by proposing the involvement of the orbitalfrontal cortex in the development of DID and suggesting a potential neurodevelopmental mechanism responsible for the development of multiple representations of self. The proposed "orbitalfrontal" model integrates and elaborates on theory and research from four domains: the neurobiology of the orbitalfrontal cortex and its protective inhibitory role in the temporal organization of behavior, the development of emotion regulation, the development of the self, and experience-dependent reorganizing neocortical processes. The hypothesis being proposed is that the experience-dependent maturation of the orbitalfrontal cortex in early abusive environments, characterized by discontinuity in dyadic socioaffective interactions between the infant and the caregiver, may be responsible for a pattern of lateral inhibition between conflicting subsets of self-representations which are normally integrated into a unified self. The basic idea is that the discontinuity in the early caretaking environment is manifested in the discontinuity in the organization of the developing child's self.
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Affiliation(s)
- K A Forrest
- University of Washington, Bothell, Washington, USA.
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Dorahy MJ. Dissociative identity disorder and memory dysfunction: the current state of experimental research and its future directions. Clin Psychol Rev 2001; 21:771-95. [PMID: 11434230 DOI: 10.1016/s0272-7358(00)00068-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Memory dysfunction is a central feature of dissociative identity disorder (DID). Following the memorial anomalies outlined by Putnam [Putnam, F. W. (1994). Dissociation and disturbances of self. In: D. Cicchetti & S. L. Toth (Eds.), Disorders and dysfunctions of the self, vol. 5 (pp. 251-265). Rochester, NY: University of Rochester Press; Putnam, F. W. (1995). Development of dissociative disorders. In: D. Chicchetti & D. J. Cohen (Eds.), Developmental psychopathology, vol. 2 (pp. 581-608). New York: Wiley], the experimental research using DID case studies and samples is reviewed. As a whole, research suggests that amnesic barriers between alter personalities are typically impervious to explicit stimuli, as well as conceptually driven implicit stimuli. Autobiographical memory deficits are also experimentally evident in DID. Although no experimental studies have addressed the issue of source amnesia or pseudomemories, there is some evidence that pseudomemories are an infrequent but real phenomenon in DID patients. Finally, potential deficits in working memory are outlined, including those relating to cognitive inhibition. Research directions are discussed throughout to further elucidate the nature of memory dysfunction in DID.
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Affiliation(s)
- M J Dorahy
- School of Psychology, University of New England, Armidale, 2351, NSW, Australia.
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Perry W, Light GA, Davis H, Braff DL. Schizophrenia patients demonstrate a dissociation on declarative and non-declarative memory tests. Schizophr Res 2000; 46:167-74. [PMID: 11120428 DOI: 10.1016/s0920-9964(99)00229-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Declarative memory refers to the recall and recognition of factual information. In contrast, non-declarative memory entails a facilitation of memory based on prior exposure and is typically assessed with priming and perceptual-motor sequencing tasks. In this study, schizophrenia patients were compared to normal comparison subjects on two computerized memory tasks: the Word-stem Priming Test (n=30) and the Pattern Sequence Learning Test (n=20). Word-stem Priming includes recall, recognition (declarative) and priming (non-declarative) components of memory. The schizophrenia patients demonstrated an impaired performance on recall of words with relative improvement during the recognition portion of the test. Furthermore, they performed normally on the priming portion of the test. Thus, on tests of declarative memory, the patients had retrieval deficits with intact performance on the non-declarative memory component. The Pattern Sequence Learning Test utilizes a serial reaction time paradigm to assess non-declarative memory. The schizophrenia patients' serial reaction time was significantly slower than that of comparison subjects. However, the patients' rate of acquisition was not different from the normal comparison group. The data suggest that patients with schizophrenia process more slowly than normal, but have an intact non-declarative memory. The schizophrenia patients' dissociation on declarative vs. non-declarative memory tests is discussed in terms of possible underlying structural impairment.
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Affiliation(s)
- W Perry
- University of California, Department of Psychiatry, 9500 Gilman drive, La Yolla, San Diego, CA 92093-8620, USA.
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Peters ML, Uyterlinde SA, Consemulder J, van der Hart O. Apparent amnesia on experimental memory tests in dissociative identity disorder: an exploratory study. Conscious Cogn 1998; 7:27-41. [PMID: 9521830 DOI: 10.1006/ccog.1997.0323] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Dissociative identity disorder (DID; called multiple personality disorder in DSMIII-R) is a psychiatric condition in which two or more identity states recurrently take control of the person's behavior. A characteristic feature of DID is the occurrence of apparently severe amnestic symptoms. This paper is concerned with experimental research of memory function in DID and focuses on between-identity transfer of newly learned neutral material. Previous studies on this subject are reviewed and a pilot study with four subjects is described. This study is specifically concerned with the question whether self-reported asymmetries in between-identity transfer can be replicated on experimental memory tests. A secondary aim was to examine whether, in the absence of explicit transfer, implicit transfer of information would occur. The results showed that the apparent amnestic asymmetry for explicit information was substantiated in the laboratory, although at least some leakage was present between the apparently amnestic identities. No evidence was found for better performance on implicit than on explicit memory tests in the apparently amnestic identities. In the discussion, parallels between apparent amnesia in DID and state-dependent memory are drawn, and the question of simulated amnesia is addressed.
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Affiliation(s)
- M L Peters
- Department of Clinical and Health Psychology, Utrecht University, The Netherlands.
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Campodonico JR, Rediess S. Dissociation of implicit and explicit knowledge in a case of psychogenic retrograde amnesia. J Int Neuropsychol Soc 1996; 2:146-58. [PMID: 9375200 DOI: 10.1017/s1355617700001004] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
There have been few studies of psychogenic amnesia based on a cognitive or neuropsychological framework. In the present study, a patient with acute onset of profound psychogenic retrograde amnesia was examined. Although her performance on neuropsychological tasks revealed intact anterograde memory, language functioning, visuospatial and constructional skills, and mental speed and flexibility, she displayed severe impairments on a variety of retrograde memory tasks. Furthermore, initial observations revealed inconsistencies between the patient's recall of semantic knowledge on direct questioning and her ability to demonstrate the use of this knowledge on indirect tasks. To test this formally, we devised an indirect remote knowledge task to examine a possible dissociation between explicit and implicit memory. Two healthy subjects matched for age, gender, education, occupation, and estimated IQ were also tested. As predicted, the findings demonstrate implicit knowledge despite impaired explicit recall for the same material.
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Affiliation(s)
- J R Campodonico
- Department of Psychiatry, University of Rochester School of Medicine, USA
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Parks ED, Balon R. Autobiographical memory for childhood events: patterns of recall in psychiatric patients with a history of alleged trauma. Psychiatry 1995; 58:199-208. [PMID: 8539301 DOI: 10.1080/00332747.1995.11024726] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Social scientists are currently being pressed upon by the legal and scientific communities to provide more definitive explanations regarding the nature and functions of memory (Loftus 1993). At the forefront of this debate is autobiographical memory. Autobiographical memory is a subclassification of memory within the declarative memory system and signifies memory for one's own personal life experiences in the recent and/or remote past. This study investigates the relationship between early trauma and memory for childhood events in adult psychiatric patients. The findings suggest that patients with an alleged history of trauma have a measurably different pattern of recall for early events than the patient and nonpatient comparison groups.
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Affiliation(s)
- E D Parks
- Department of Psychiatry, Wayne State University School of Medicine, MI, USA
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32
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Freyd JJ. Betrayal Trauma: Traumatic Amnesia as an Adaptive Response to Childhood Abuse. ETHICS & BEHAVIOR 1994. [DOI: 10.1207/s15327019eb0404_1] [Citation(s) in RCA: 220] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Armstrong JG. Reflections on multiple personality disorder as a developmentally complex adaptation. PSYCHOANALYTIC STUDY OF THE CHILD 1994; 49:349-64. [PMID: 7809294 DOI: 10.1080/00797308.1994.11823068] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Recent advances in the understanding of multiple personality disorder provide the groundwork for its creative reconciliation with psychoanalysis. This paper uses psychoanalytic, modern developmental, and psychological assessment perspectives to conceptualize multiple personality disorder as a developmentally protective response to chronic childhood trauma. Implications of this theory for clinical work with these patients are discussed.
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Affiliation(s)
- J G Armstrong
- Dissociative Disorders Program, Sheppard and Enoch Pratt Hospital
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Demitrack MA, Putnam FW, Rubinow DR, Pigott TA, Altemus M, Krahn DD, Gold PW. Relation of dissociative phenomena to levels of cerebrospinal fluid monoamine metabolites and beta-endorphin in patients with eating disorders: a pilot study. Psychiatry Res 1993; 49:1-10. [PMID: 7511247 DOI: 10.1016/0165-1781(93)90026-d] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Dissociation is made manifest by a failure to integrate thoughts, feelings, memories, and actions into a unified sense of consciousness. Although dissociation is presumed to be a special state of consciousness manifested by state-dependent memory and physiology, the psychobiology of dissociation is poorly understood. In this study, we examined cerebrospinal fluid levels of the major monoamine metabolites and beta-endorphin in patients with eating disorders (11 with anorexia nervosa, 16 with bulimia nervosa), while they were acutely ill. Dissociative capacity was measured using the Dissociative Experiences Scale (DES). We provide evidence that neurochemical changes in dopaminergic, serotonergic, and opioid systems may be associated with the clinical expression of dissociation in patients with eating disorders during the acute phase of their illness. These preliminary results are compatible with previous studies of neurochemical disturbances in the eating disorders and suggest that future work in dissociation should specifically include examination of these neurobiologic systems.
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Affiliation(s)
- M A Demitrack
- Department of Psychiatry, University of Michigan, Ann Arbor
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Abstract
Although there is a general consensus among concerned professionals that exposure to community violence is likely to be stressful and may contribute significantly to immediate and long-term mental health problems, there is virtually no empirical research on either its acute or enduring effects. In the absence of data, investigators planning research in this area must look to other studies of the impact of chronic environmental trauma on children, including the effects of war and child maltreatment. Research on child abuse provides an important source of information on the effects of trauma on children because it draws on both prospective and retrospective studies crossing a variety of theoretical perspectives and disciplines. The existence of data on both the acute impact of abuse on children and its chronic effects and outcomes in adults informs the generation of developmentally based psychological and biological hypotheses. This paper utilizes data from research on the acute and chronic effects of sexual abuse to discuss three broad hypotheses that may be relevant to the study of the effects of community violence on children.
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Affiliation(s)
- F W Putnam
- Laboratory of Developmental Psychology, National Institute of Mental Health, Bethesda, MD 20892
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Putnam FW. Dissociative disorders in children: behavioral profiles and problems. CHILD ABUSE & NEGLECT 1993; 17:39-45. [PMID: 8435785 DOI: 10.1016/0145-2134(93)90006-q] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Transient dissociative episodes are a common and normative phenomenon during childhood that generally decrease during adolescence to relatively low levels in adults. Retrospective clinical research has firmly established a connection between childhood trauma and the development of dissociative disorders in adults. A growing number of clinicians are now identifying dissociative symptoms in abused children, and there is increasing evidence that dissociative disorders represent a significant and hitherto unrecognized form of psychopathology in traumatized children. Pathological dissociation is a complex psychobiological process that results in a failure to integrate information into the normal stream of consciousness. It produces a range of symptoms and behaviors including: (a) amnesias; (b) disturbances in sense of self; (c) trance-like states; (d) rapid shifts in mood and behavior; (e) perplexing shifts in access to knowledge, memory, and skills; (f) auditory and visual hallucinations; and (g) vivid imaginary companionship in children and adolescents. Many of these symptoms and behaviors are misdiagnosed as attention, learning or conduct problems, or even psychoses. Early identification and therapeutic intervention appear to be particularly efficacious in children in contrast to adults, although systematic studies of treatment and outcome are presently lacking.
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Affiliation(s)
- F W Putnam
- National Institute of Mental Health, Bethesda, MD 20895
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Abstract
The cardinal feature of multiple personality disorder (MPD) is the existence of two or more alter personality states that exchange control over the behaviour of an individual. Numerous clinical reports suggest that these alter personality states exhibit distinct physiological differences. We investigated differential autonomic nervous system (ANS) activity across nine subjects with MPD and five controls, who produced "alter" personality states by simulation and by hypnosis or deep relaxation. Eight of the nine MPD subjects consistently manifested physiologically distinct alter personality states. Three of the five controls were also produced physiologically distinct states, but these differed from those of the MPD subjects. A habituation paradigm demonstrated carryover effects at the ANS levels from one state to the next for both groups.
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Affiliation(s)
- F W Putnam
- Unit on Dissociative Disorders, National Institute of Mental Health, Bethesda, MD 20892
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