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Staniloiu A, Markowitsch HJ. Dissociative Amnesia: Remembrances Under Cover. Top Cogn Sci 2024. [PMID: 38728576 DOI: 10.1111/tops.12734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 03/29/2024] [Accepted: 04/01/2024] [Indexed: 05/12/2024]
Abstract
The existence or questionability of "repressed memories" can be discussed as being a matter of definition. It seems, however, far-fetched to consider all "lost" memories as caused by encoding problems, brain damage, forgetfulness, failure to disclose events, and so on. We argue that dissociative amnesia (DA) (or "psychogenic amnesia," or "functional amnesia," or, as we favor to call it, "mnestic block syndrome") is caused by psychic alterations, but ultimately they can be traced to changes in the physiology of the brain, as we are of the opinion that all memory processes-positive or negative-alter brain functions, sometimes more permanently, sometimes transiently. We have proven this idea using functional imaging techniques, in particular fluoro-deoxy-d-glucose positron emission tomography. Having investigated dozens of patients with severe and long-lasting DA conditions, we believe it to be disrespectful to many (but not to all) of the affected patients to question their disease condition, which can be proven to be not caused by feigning, malingering, or direct brain damage.
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Affiliation(s)
- Angelica Staniloiu
- Department of Physiological Psychology, University of Bielefeld
- Department of Psychology, University of Bucharest
- Psychiatry and Psychosomatics, Oberberg Clinic Hornberg
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2
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Kirschen GW, Shorey ME, Han J, Leppla I, Masear CG, Robinson J. Dissociative identity precipitated by emergence from general anesthesia: A case report and analytical framework. PSYCHIATRY RESEARCH CASE REPORTS 2023; 2:100152. [PMID: 37614702 PMCID: PMC10443949 DOI: 10.1016/j.psycr.2023.100152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Abstract
Background Dissociative identity disorder (DID) is a complex and controversial psychiatric condition in which one person maintains at least two separate and distinct personalities. Patients with DID often report a history of childhood abuse and may have other comorbid psychiatric conditions. Psychosocial stressors may be triggers for DID inception or recurrence. While anesthetic agents, in particular ketamine, may induce a temporary dissociative state, it has not yet been reported that anesthesia can precipitate a dissociative identity. Case report We report a case of a woman with a history of childhood sexual abuse and past suicide attempt who experienced an episode of dissociative identity on emergence from anesthesia. The episode resolved within 90 minutes and the patient was discharged home safely on hospital day two. Conclusion This case adds to the literature of potentially precipitating factors of DID and we provide a unifying mechanistic hypothesis linking anesthesia to functional brain connectivity.
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Affiliation(s)
- Gregory W. Kirschen
- Department of Gynecology & Obstetrics, The Johns Hopkins Hospital, Baltimore, MD, 21287
| | - Mary E. Shorey
- Department of Gynecology & Obstetrics, The Johns Hopkins Hospital, Baltimore, MD, 21287
- Department of Complex Family Planning, Johns Hopkins Bayview Medical Center, Baltimore, MD 21224
| | - Joan Han
- Department of Psychiatry, The Johns Hopkins Hospital, Baltimore, MD, 21287
| | - Idris Leppla
- Department of Psychiatry, The Johns Hopkins Hospital, Baltimore, MD, 21287
| | - Courtney G. Masear
- Department of Anesthesiology, The Johns Hopkins Hospital, Baltimore, MD, 21287
| | - Jennifer Robinson
- Department of Gynecology & Obstetrics, The Johns Hopkins Hospital, Baltimore, MD, 21287
- Department of Complex Family Planning, Johns Hopkins Bayview Medical Center, Baltimore, MD 21224
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3
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Markowitsch HJ, Staniloiu A. Behavioral, neurological, and psychiatric frailty of autobiographical memory. WILEY INTERDISCIPLINARY REVIEWS. COGNITIVE SCIENCE 2023; 14:e1617. [PMID: 35970754 DOI: 10.1002/wcs.1617] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 07/01/2022] [Accepted: 07/03/2022] [Indexed: 05/20/2023]
Abstract
Autobiographical-episodic memory is considered to be the most complex of the five long-term memory systems. It is autonoetic, which means, self-reflective, relies on emotional colorization, and needs the features of place and time; it allows mental time traveling. Compared to the other four long-term memory systems-procedural memory, priming, perceptual, and semantic memory-it develops the latest in phylogeny and ontogeny, and is the most vulnerable of the five systems, being easily impaired by brain damage and psychiatric disorders. Furthermore, it is characterized by its fragility and proneness to distortion due to environmental influences and subsequent information. On the brain level, a distinction has to be made between memory encoding and consolidating, memory storage, and memory retrieval. For encoding, structures of the limbic system, with the hippocampus in its center, are crucial, for storage of widespread cortical networks, and for retrieval again a distributed recollection network, in which the prefrontal cortex plays a crucial role, is engaged. Brain damage and psychiatric diseases can lead to what is called "focal retrograde amnesia." In this context, the clinical picture of dissociative or functional or psychogenic amnesia is central, as it may result in autobiographical-emotional amnesia of the total past with the consequence of an impairment of the self as well. The social environment therefore can have a major impact on the brain and on autobiographical-episodic memory processing. This article is categorized under: Psychology > Memory.
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Affiliation(s)
- Hans J Markowitsch
- Department of Physiological Psychology, University of Bielefeld, Bielefeld, Germany
| | - Angelica Staniloiu
- Department of Physiological Psychology, University of Bielefeld, Bielefeld, Germany
- Oberberg Clinic, Hornberg, Germany
- Department of Psychology, University of Bucharest, Bucharest, Romania
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4
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Taïb S, Yrondi A, Lemesle B, Péran P, Pariente J. What are the neural correlates of dissociative amnesia? A systematic review of the functional neuroimaging literature. Front Psychiatry 2023; 14:1092826. [PMID: 36778638 PMCID: PMC9909275 DOI: 10.3389/fpsyt.2023.1092826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 01/09/2023] [Indexed: 01/27/2023] Open
Abstract
AIM Dissociative amnesia is an emblematic psychiatric condition in which patients experience massive memory loss ranging from focal to global amnesia. This condition remains poorly understood and this review aims to investigate the neuroanatomical feature of this disease. METHODS We conducted a systematic review of the scientific literature available on PubMed, up to December 1, 2022, using a combination of keywords referring to dissociative amnesia. We included every scientific report involving patients undergoing a functional imaging procedure. RESULTS Twenty-two studies met our inclusion criteria (gathering 49 patients). Only one was a controlled study with a large sample. The other 21 were case reports and case series. In resting state, neuroimaging studies mostly showed a hypo-activated right inferolateral prefrontal cortex, associated with limbic hypoactivity and lesser activation of the hippocampal and para-hippocampal structures. The patients also presented abnormal patterns of cerebral activation when performing memory tasks. When testing recognition of memories from the amnestic period, patients showed increased activation across temporal areas (hippocampal and para-hippocampal gyri) and the limbic network. When trying to recollect memories from an amnestic period compared to a non-amnestic period, patients failed to activate these structures efficiently. Most of these patterns tended to return to normal when symptoms resolved. CONCLUSION This review identified a paucity of controlled studies in the field of dissociative amnesia neuroimaging, which restricts the extrapolation of results. Patients with dissociative amnesia present a broad prefronto-temporo-limbic network dysfunction. Some of the brain areas implicated in this network might represent potential targets for innovative treatments.
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Affiliation(s)
- Simon Taïb
- INSERM U1214 Centre d'Imagerie Neuro Toulouse (ToNIC), Toulouse, France.,Service de Psychiatrie, Psychothérapie et Art-Thérapie, Centre Expert du Stress Traumatique, CHU de Toulouse, Toulouse, France
| | - Antoine Yrondi
- INSERM U1214 Centre d'Imagerie Neuro Toulouse (ToNIC), Toulouse, France.,Service Universitaire de Psychiatrie et Psychologie Médicale, CHU de Toulouse, Toulouse, France
| | | | - Patrice Péran
- INSERM U1214 Centre d'Imagerie Neuro Toulouse (ToNIC), Toulouse, France
| | - Jérémie Pariente
- INSERM U1214 Centre d'Imagerie Neuro Toulouse (ToNIC), Toulouse, France.,Pôle Neurosciences, CHU de Toulouse, Toulouse, France
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Huntjens RJC, Otgaar H, Pijnenborg GHM, Wessel I. The elusive search for a biomarker of dissociative amnesia: a reaction to Dimitrova et al. (2021). Psychol Med 2022; 52:2835-2836. [PMID: 35550208 PMCID: PMC9647544 DOI: 10.1017/s0033291722001118] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 03/30/2022] [Accepted: 03/30/2022] [Indexed: 12/30/2022]
Affiliation(s)
- R. J. C. Huntjens
- Clinical Psychology and Experimental Psychopathology, University of Groningen, Groningen, the Netherlands
| | - H. Otgaar
- Clinical Psychological Science, Maastricht University, Maastricht, the Netherlands
- Faculty of Law and Criminology, KU Leuven, Leuven, Belgium
| | - G. H. M. Pijnenborg
- Clinical and Developmental Neuropsychology, University of Groningen, Groningen, the Netherlands
| | - I. Wessel
- Clinical Psychology and Experimental Psychopathology, University of Groningen, Groningen, the Netherlands
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6
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Tsur N, Katz C. "And Then Cinderella Was Lying in My Bed": Dissociation Displays in Forensic Interviews With Children Following Intrafamilial Child Sexual Abuse. JOURNAL OF INTERPERSONAL VIOLENCE 2022; 37:NP15336-NP15358. [PMID: 34000885 DOI: 10.1177/08862605211016347] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Child sexual abuse (CSA) has been implicated in dissociative peritraumatic and post-traumatic symptoms and disorders. Although explicitly relevant to the legal process following alleged CSA, very little is known about dissociative manifestations in the context of forensic interviews with children following abuse. The current study was designed to uncoverperi- and post-traumatic dissociation of abused children as revealed in forensic interviews. The study examines the display of dissociation in 42 forensic interviews with children (29 girls, aged 4-14) following intra familial child sexual abuse (IFCSA). Thematic analysis was used to identify key expressions of dissociation in all of the forensic interviews. The analyses identified depersonalization and derealization in the children's description of the abuse. This was manifested both in an inability to feel things that happened during the incidents or imagination and fantasies that were reported as part of the abusive incidents. The children's interviews also revealed the potential manifestations of dissociative amnesia, which was evident in the children's attempts to communicate their retrieval difficulties to the forensic interviewers. Finally, it was identified that the forensic interviews were a platform in which dissociative post-traumatic reactions were activated and often displayed in sensory flashbacks. The current findings uncover the importance of acknowledging trauma and dissociation in the context of forensic interviews with abused children and the urgent need to implement unique responses to trauma within practical guidelines.
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Affiliation(s)
- Noga Tsur
- Tel Aviv University, Tel Aviv, Israel
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Modesti MN, Rapisarda L, Capriotti G, Del Casale A. Functional Neuroimaging in Dissociative Disorders: A Systematic Review. J Pers Med 2022; 12:jpm12091405. [PMID: 36143190 PMCID: PMC9502311 DOI: 10.3390/jpm12091405] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 08/21/2022] [Accepted: 08/26/2022] [Indexed: 11/16/2022] Open
Abstract
Background: Dissociative disorders encompass loss of integration in essential functions such as memory, consciousness, perception, motor control, and identity. Nevertheless, neuroimaging studies, albeit scarce, have suggested the existence of particular brain activation patterns in patients belonging to this diagnostic category. The aim of this review is to identify the main functional neuroimaging correlates of dissociative disorders. Methods: we searched the PubMed database to identify functional neuroimaging studies conducted on subjects with a diagnosis of a dissociative disorder, following the PRISMA guidelines. In the end, we included 13 studies in this systematic review, conducted on 51 patients with dissociative identity disorder (DID), 28 subjects affected by depersonalization disorder, 24 with dissociative amnesia, and 6 with other or not specified dissociative disorders. Results: Prefrontal cortex dysfunction seems prominent. In addition, changes in the functional neural network of the caudate are related to alterations of identity state and maintenance of an altered mental status in DID. Another role in DID seems to be played by a dysfunction of the anterior cingulate gyrus. Other regions, including parietal, temporal, and insular cortices, and subcortical areas were reported to be dysfunctional in dissociative disorders. Conclusions: Prefrontal dysfunction is frequently reported in dissociative disorders. Functional changes in other cortical and subcortical areas can be correlated with these diagnoses. Further studies are needed to clarify the neurofunctional correlations of each dissociative disorder in affected patients, in order to identify better tailored treatments.
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Affiliation(s)
- Martina Nicole Modesti
- Faculty of Medicine and Psychology, Sapienza University of Rome, Via di Grottarossa 1035, 00189 Rome, Italy
| | - Ludovica Rapisarda
- Faculty of Medicine and Psychology, Sapienza University of Rome, Via di Grottarossa 1035, 00189 Rome, Italy
| | - Gabriela Capriotti
- Unit of Nuclear Medicine, Department of Medical-Surgical Sciences and Translational Medicine, Faculty of Medicine and Psychology, Sant’Andrea University Hospital, Sapienza University of Rome, Via di Grottarossa 1035, 00189 Rome, Italy
| | - Antonio Del Casale
- Unit of Psychiatry, Department of Dynamic and Clinical Psychology, Faculty of Medicine and Psychology, Sant’Andrea University Hospital, Sapienza University of Rome, Via di Grottarossa 1035, 00189 Rome, Italy
- Correspondence:
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Forgetting the Unforgettable: Transient Global Amnesia Part II: A Clinical Road Map. J Clin Med 2022; 11:jcm11143940. [PMID: 35887703 PMCID: PMC9319625 DOI: 10.3390/jcm11143940] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 07/03/2022] [Accepted: 07/05/2022] [Indexed: 12/14/2022] Open
Abstract
Transient global amnesia (TGA) is a clinical syndrome characterized by the sudden onset of a temporary memory disorder with profound anterograde amnesia and a variable impairment of the past memory. Usually, the attacks are preceded by a precipitating event, last up to 24 h and are not associated with other neurological deficits. Diagnosis can be challenging because the identification of TGA requires the exclusion of some acute amnestic syndromes that occur in emergency situations and share structural or functional alterations of memory circuits. Magnetic Resonance Imaging (MRI) studies performed 24–96 h after symptom onset can help to confirm the diagnosis by identifying lesions in the CA1 field of the hippocampal cornu ammonis, but their practical utility in changing the management of patients is a matter of discussion. In this review, we aim to provide a practical approach to early recognition of this condition in daily practice, highlighting both the lights and the shadows of the diagnostic criteria. For this purpose, we summarize current knowledge about the clinical presentation, diagnostic pathways, differential diagnosis, and the expected long-term outcome of TGA.
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9
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Wolf MR, Nochajski TH. ‘Black Holes’ in memory: Childhood autobiographical memory loss in adult survivors of child sexual abuse. EUROPEAN JOURNAL OF TRAUMA & DISSOCIATION 2022. [DOI: 10.1016/j.ejtd.2021.100234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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10
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The Memory-Undermining Effect of Simulated Crime-Related Amnesia and Its Legal Implications: a Review. PSYCHOLOGICAL INJURY & LAW 2021. [DOI: 10.1007/s12207-021-09441-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
AbstractPretending to suffer from amnesia for a mock crime has been shown to lead to memory impairments. Specifically, when people are asked to give up their role of simulators, they typically recall fewer crime-relevant details than those who initially confess to a crime. In the current review, we amassed all experimental work on this subject and assessed the characteristics of the memory-undermining effect of simulated amnesia for a crime procedure (i.e., crime stimuli, simulating amnesia instructions, memory tests, and memory outcomes). We specifically focused on the effect that crime-related amnesia claims may have on offenders’ final memory reports. Our review showed that simulators who initially claimed amnesia might paradoxically experience some sort of forgetting pertaining to crime-related information. This issue could likely lead to legal complications that need be taken into account in crime-related amnesia cases.
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11
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Dodier O. L’amnésie dissociative : limites méthodologiques, limites conceptuelles, et explications alternatives. ANNEE PSYCHOLOGIQUE 2021. [DOI: 10.3917/anpsy1.213.0275] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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12
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Hertrich I, Dietrich S, Blum C, Ackermann H. The Role of the Dorsolateral Prefrontal Cortex for Speech and Language Processing. Front Hum Neurosci 2021; 15:645209. [PMID: 34079444 PMCID: PMC8165195 DOI: 10.3389/fnhum.2021.645209] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Accepted: 04/06/2021] [Indexed: 11/24/2022] Open
Abstract
This review article summarizes various functions of the dorsolateral prefrontal cortex (DLPFC) that are related to language processing. To this end, its connectivity with the left-dominant perisylvian language network was considered, as well as its interaction with other functional networks that, directly or indirectly, contribute to language processing. Language-related functions of the DLPFC comprise various aspects of pragmatic processing such as discourse management, integration of prosody, interpretation of nonliteral meanings, inference making, ambiguity resolution, and error repair. Neurophysiologically, the DLPFC seems to be a key region for implementing functional connectivity between the language network and other functional networks, including cortico-cortical as well as subcortical circuits. Considering clinical aspects, damage to the DLPFC causes psychiatric communication deficits rather than typical aphasic language syndromes. Although the number of well-controlled studies on DLPFC language functions is still limited, the DLPFC might be an important target region for the treatment of pragmatic language disorders.
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Affiliation(s)
- Ingo Hertrich
- Department of Neurology and Stroke, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Susanne Dietrich
- Evolutionary Cognition, Department of Psychology, University of Tübingen, Tübingen, Germany
| | - Corinna Blum
- Department of Neurology and Stroke, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
| | - Hermann Ackermann
- Department of Neurology and Stroke, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
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13
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Trakas M. No trace beyond their name? Affective Memories, a forgotten concept. ANNEE PSYCHOLOGIQUE 2021. [DOI: 10.3917/anpsy1.212.0129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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14
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Piedfort-Marin O, Rignol G, Tarquinio C. Le trouble dissociatif de l’identité : les mythes à l’épreuve des recherches scientifiques. ANNALES MEDICO-PSYCHOLOGIQUES 2021. [DOI: 10.1016/j.amp.2021.02.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Gunasekara R, Chida S, Shahid M, Begum G, Jolayemi A. A Case of Post-Traumatic Retrograde and Anterograde Loss of Autobiographical Memory in the Absence of Medial Temporal Lobe Lesion. Cureus 2020; 12:e11898. [PMID: 33415050 PMCID: PMC7781873 DOI: 10.7759/cureus.11898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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Roydeva MI, Reinders AATS. Biomarkers of Pathological Dissociation: A Systematic Review. Neurosci Biobehav Rev 2020; 123:120-202. [PMID: 33271160 DOI: 10.1016/j.neubiorev.2020.11.019] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 08/20/2020] [Accepted: 11/15/2020] [Indexed: 02/06/2023]
Abstract
Pathological dissociation is a severe, debilitating and transdiagnostic psychiatric symptom. This review identifies biomarkers of pathological dissociation in a transdiagnostic manner to recommend the most promising research and treatment pathways in support of the precision medicine framework. A total of 205 unique studies that met inclusion criteria were included. Studies were divided into four biomarker categories, namely neuroimaging, psychobiological, psychophysiological and genetic biomarkers. The dorsomedial and dorsolateral prefrontal cortex, bilateral superior frontal regions, (anterior) cingulate, posterior association areas and basal ganglia are identified as neurofunctional biomarkers of pathological dissociation and decreased hippocampal, basal ganglia and thalamic volumes as neurostructural biomarkers. Increased oxytocin and prolactin and decreased tumor necrosis factor alpha (TNF-α) are identified as psychobiological markers. Psychophysiological biomarkers, including blood pressure, heart rate and skin conductance, were inconclusive. For the genetic biomarker category studies related to dissociation were limited and no clear directionality of effect was found to warrant identification of a genetic biomarker. Recommendations for future research pathways and possible clinical applicability are provided.
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Affiliation(s)
- Monika I Roydeva
- Department of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, United Kingdom
| | - Antje A T S Reinders
- Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, United Kingdom.
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Zorzo C, Arias JL, Méndez M. Retrieval of allocentric spatial memories is preserved up to thirty days and does not require higher brain metabolic demands. Neurobiol Learn Mem 2020; 175:107312. [DOI: 10.1016/j.nlm.2020.107312] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 07/17/2020] [Accepted: 08/30/2020] [Indexed: 01/13/2023]
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18
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Acute amnestic syndromes. J Neurol Sci 2020; 413:116781. [PMID: 32203745 DOI: 10.1016/j.jns.2020.116781] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 03/09/2020] [Accepted: 03/16/2020] [Indexed: 11/22/2022]
Abstract
Acute amnestic syndromes are usually rare clinical events occurring in emergency situations. Etiological diagnosis can be challenging and underlying causes diverse. They can be transient and totally reversible, or accompanied by other neurological symptoms resulting in serious and irreversible brain damage. Pathophysiology of these syndromes mainly corresponds to structural or functional alteration of memory circuits, including those in the hippocampus. One of the most frequent forms is transient global amnesia (TGA), characterized by sudden onset of anterograde amnesia lasting less than 24 hours, in the absence of other neurological signs or symptoms. Another acute and transient memory disorder is transient epileptic amnesia (TEA), due to focal crisis activity. Stroke injuries occurring at strategic memory-related sites can also present as sudden episodes of amnesia. In addition to neurological etiologies, amnesia may be a symptom of a psychiatric disorder (dissociative amnesia). Traumatic brain injuries, autoimmune encephalitis and acute toxic metabolic disorders can also cause amnesia and should be included among the differential diagnoses. In this review, we summarize the most relevant clinical findings in acute amnestic syndromes, and discuss the different ancillary tests needed to establish a correct diagnosis and management as well the best treatment options. Relevant anatomical and pathophysiological aspects underlying these conditions will be also be presented.
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19
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Staniloiu A, Kordon A, Markowitsch HJ. Stress- and trauma-related blockade of episodic-autobiographical memory processing. Neuropsychologia 2020; 139:107364. [PMID: 32006541 DOI: 10.1016/j.neuropsychologia.2020.107364] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2019] [Revised: 01/14/2020] [Accepted: 01/24/2020] [Indexed: 12/21/2022]
Abstract
Memory disorders without a direct neural substrate still belong to the riddles in neuroscience. Although they were for a while dissociated from research and clinical arenas, risking becoming forgotten diseases, they sparked novel interests, paralleling the refinements in functional neuroimaging and neuropsychology. Although Endel Tulving has not fully embarked himself on exploring this field, he had published at least one article on functional amnesia (Schacter et al., 1982) and ignited a seminal article on amnesia with mixed etiology (Craver et al., 2014). Most importantly, the research of Endel Tulving has provided the researchers and clinicians in the field of dissociative or functional amnesia with the best framework for superiorly understanding these disorders through the lens of his evolving concept of episodic memory and five long term memory systems classification, which he developed and advanced. Herein we use the classification of long-term memory systems of Endel Tulving as well as his concepts and views on autonoetic consciousness, relationships between memory systems and relationship between episodic memory and emotion to describe six cases of dissociative amnesia that put a challenge for researchers and clinicians due to their atypicality. We then discuss their possible triggering and maintaining mechanisms, pointing to their clinical heterogeneity and multifaceted causally explanatory frameworks.
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Affiliation(s)
- Angelica Staniloiu
- University of Bielefeld, Germany; University of Bucharest, Romania; Oberberg Clinic Hornberg, Germany
| | - Andreas Kordon
- Oberberg Clinic Hornberg, Germany; University of Freiburg, Germany
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20
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Abstract
The memory impairment of neurological and psychiatric patients is seen as occurring mainly in the autobiographical-episodic memory domain and this is considered to depend on limbic structures such as the amygdala or the septal nuclei. Especially the amygdala is a hub for giving an emotional flavor to personal memories. Bastin et al. fail to include the amygdala in their integrative memory model.
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21
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Mitsui N, Oyanagi Y, Kako Y, Kusumi I. Natural recovery from long-lasting generalised dissociative amnesia and of cerebral blood flow. BMJ Case Rep 2019; 12:12/12/e231270. [PMID: 31831515 DOI: 10.1136/bcr-2019-231270] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
A 40-year-old man presented with generalised dissociative amnesia. At 2 weeks after onset, N-isopropyl-[123I] p-iodoamphetamine-single-photon emission CT imaging of the brain revealed hypoperfusion in the right medial temporal area. Organic brain damage was ruled out. His inability to recall information was attributed to psychological stress related to his employment. Consistent with this diagnosis, his generalised dissociative amnesia lasted 6 years and 10 months; however, he recovered from amnesia naturally on starting a new job. Perfusion of his right medial temporal area also returned to normal levels. Longitudinal reports for generalised dissociative amnesia with natural recovery are exceedingly rare. It is important to confirm whether dissociative amnesia and cerebral blood flow recover in parallel, even in cases where dissociative amnesia is long-lasting.
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Affiliation(s)
| | - Yuka Oyanagi
- Psychiatry, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Yuki Kako
- Psychiatry, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Ichiro Kusumi
- Psychiatry, Hokkaido University, Sapporo, Hokkaido, Japan
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Abstract
OBJECTIVES In this paper, I review three 'anomalies' or disorders in autobiographical memory: neurological retrograde amnesia (RA), spontaneous confabulation, and psychogenic amnesia. METHODS Existing theories are reviewed, their limitations considered, some of my own empirical findings briefly described, and possible interpretations proposed and interspersed with illustrative case-reports. RESULTS In RA, there may be an important retrieval component to the deficit, and factors at encoding may give rise to the relative preservation of early memories (and the reminiscence bump) which manifests as a temporal gradient. Spontaneous confabulation appears to be associated with a damaged 'filter' in orbitofrontal and ventromedial frontal regions. Consistent with this, an empirical study has shown that both the initial severity of confabulation and its subsequent decline are associated with changes in the executive function (especially in cognitive estimate errors) and inversely with the quantity of accurate autobiographical memories retrieved. Psychogenic amnesia can be 'global' or 'situation-specific'. The former is associated with a precipitating stress, depressed mood, and (often) a past history of a transient neurological amnesia. In these circumstances, frontal control mechanisms can inhibit retrieval of autobiographical memories, and even the sense of 'self' (identity), while compromised medial temporal function prevents subsequent retrieval of what occurred during a 'fugue'. An empirical investigation of psychogenic amnesia and some recent imaging studies have provided findings consistent with this view. CONCLUSIONS Taken together, these various observations point to the importance of frontal 'control' systems (in interaction with medial temporal/hippocampal systems) in the retrieval and, more particularly, the disrupted retrieval of 'old' memories.
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Discourse management during speech perception: A functional magnetic resonance imaging (fMRI) study. Neuroimage 2019; 202:116047. [DOI: 10.1016/j.neuroimage.2019.116047] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 07/09/2019] [Accepted: 07/22/2019] [Indexed: 11/22/2022] Open
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Chechko N, Stickel S, Kellermann T, Kirner A, Habel U, Fernández G, Schneider F, Kohn N. Progressively analogous evidence of covert face recognition from functional magnetic resonance imaging and skin conductance responses studies involving a patient with dissociative amnesia. Eur J Neurosci 2018; 48:1964-1975. [DOI: 10.1111/ejn.14087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 06/04/2018] [Accepted: 06/22/2018] [Indexed: 12/23/2022]
Affiliation(s)
- Natalya Chechko
- Department of Psychiatry, Psychotherapy and Psychosomatics; Medical Faculty; RWTH Aachen; Aachen Germany
- JARA-Institute Brain Structure Function Relationship; Research Center Juelich and RWTH Aachen University; Aachen Germany
- Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10); Research Center Jülich; Jülich Germany
| | - Susanne Stickel
- Department of Psychiatry, Psychotherapy and Psychosomatics; Medical Faculty; RWTH Aachen; Aachen Germany
- JARA-Institute Brain Structure Function Relationship; Research Center Juelich and RWTH Aachen University; Aachen Germany
| | - Thilo Kellermann
- Department of Psychiatry, Psychotherapy and Psychosomatics; Medical Faculty; RWTH Aachen; Aachen Germany
- JARA-Institute Brain Structure Function Relationship; Research Center Juelich and RWTH Aachen University; Aachen Germany
| | - Andre Kirner
- Department of Psychiatry, Psychotherapy and Psychosomatics; Medical Faculty; RWTH Aachen; Aachen Germany
| | - Ute Habel
- Department of Psychiatry, Psychotherapy and Psychosomatics; Medical Faculty; RWTH Aachen; Aachen Germany
- JARA-Institute Brain Structure Function Relationship; Research Center Juelich and RWTH Aachen University; Aachen Germany
- Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10); Research Center Jülich; Jülich Germany
| | - Guillén Fernández
- Department of Cognitive Neuroscience; Radboud University Medical Centre; Donders Institute for Brain, Cognition and Behaviour; Nijmegen The Netherlands
| | - Frank Schneider
- Department of Psychiatry, Psychotherapy and Psychosomatics; Medical Faculty; RWTH Aachen; Aachen Germany
- JARA-Institute Brain Structure Function Relationship; Research Center Juelich and RWTH Aachen University; Aachen Germany
- Institute of Neuroscience and Medicine: JARA-Institute Brain Structure Function Relationship (INM 10); Research Center Jülich; Jülich Germany
| | - Nils Kohn
- Department of Psychiatry, Psychotherapy and Psychosomatics; Medical Faculty; RWTH Aachen; Aachen Germany
- Department of Cognitive Neuroscience; Radboud University Medical Centre; Donders Institute for Brain, Cognition and Behaviour; Nijmegen The Netherlands
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25
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Inserra A. Hypothesis: The Psychedelic Ayahuasca Heals Traumatic Memories via a Sigma 1 Receptor-Mediated Epigenetic-Mnemonic Process. Front Pharmacol 2018; 9:330. [PMID: 29674970 PMCID: PMC5895707 DOI: 10.3389/fphar.2018.00330] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 03/21/2018] [Indexed: 12/21/2022] Open
Abstract
Ayahuasca ingestion modulates brain activity, neurotransmission, gene expression and epigenetic regulation. N,N-Dimethyltryptamine (DMT, one of the alkaloids in Ayahuasca) activates sigma 1 receptor (SIGMAR1) and others. SIGMAR1 is a multi-faceted stress-responsive receptor which promotes cell survival, neuroprotection, neuroplasticity, and neuroimmunomodulation. Simultaneously, monoamine oxidase inhibitors (MAOIs) also present in Ayahuasca prevent the degradation of DMT. One peculiarity of SIGMAR1 activation and MAOI activity is the reversal of mnemonic deficits in pre-clinical models. Since traumatic memories in post-traumatic stress disorder (PTSD) are often characterised by “repression” and PTSD patients ingesting Ayahuasca report the retrieval of such memories, it cannot be excluded that DMT-mediated SIGMAR1 activation and the concomitant MAOIs effects during Ayahuasca ingestion might mediate such “anti-amnesic” process. Here I hypothesise that Ayahuasca, via hyperactivation of trauma and emotional memory-related centres, and via its concomitant SIGMAR1- and MAOIs- induced anti-amnesic effects, facilitates the retrieval of traumatic memories, in turn making them labile (destabilised). As Ayahuasca alkaloids enhance synaptic plasticity, increase neurogenesis and boost dopaminergic neurotransmission, and those processes are involved in memory reconsolidation and fear extinction, the fear response triggered by the memory can be reprogramed and/or extinguished. Subsequently, the memory is stored with this updated significance. To date, it is unclear if new memories replace, co-exist with or bypass old ones. Although the mechanisms involved in memory are still debated, they seem to require the involvement of cellular and molecular events, such as reorganisation of homo and heteroreceptor complexes at the synapse, synaptic plasticity, and epigenetic re-modulation of gene expression. Since SIGMAR1 mobilises synaptic receptor, boosts synaptic plasticity and modulates epigenetic processes, such effects might be involved in the reported healing of traumatic memories in PTSD patients. If this theory proves to be true, Ayahuasca could come to represent the only standing pharmacological treatment which targets traumatic memories in PTSD. Lastly, since SIGMAR1 activation triggers both epigenetic and immunomodulatory programmes, the mechanism here presented could help understanding and treating other conditions in which the cellular memory is dysregulated, such as cancer, diabetes, autoimmune and neurodegenerative pathologies and substance addiction.
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Affiliation(s)
- Antonio Inserra
- Mind and Brain Theme, The South Australian Health and Medical Research Institute, Adelaide, SA, Australia.,Department of Psychiatry, College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia.,Centre for Neuroscience, Flinders University, Adelaide, SA, Australia
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Staniloiu A, Markowitsch HJ, Kordon A. Psychological causes of autobiographical amnesia: A study of 28 cases. Neuropsychologia 2018; 110:134-147. [DOI: 10.1016/j.neuropsychologia.2017.10.017] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 09/26/2017] [Accepted: 10/15/2017] [Indexed: 12/28/2022]
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27
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Staniloiu A, Wahl-Kordon A, Markowitsch HJ. Dissoziative Amnesie und Migration. ZEITSCHRIFT FÜR NEUROPSYCHOLOGIE 2017. [DOI: 10.1024/1016-264x/a000198] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Zusammenfassung. Dissoziative Amnesie verläuft unter Umständen chronisch und kann zu lebenslanger Arbeitsunfähigkeit führen. Die Krankheit tritt gehäuft im Zusammenhang mit Migration auf und verläuft dann schwerer als in anderen Fällen. Sie ist im Grunde reversibel, d. h., der Abruf der Gedächtnisinhalte ist nur blockiert. Betroffen sind Patienten, die nicht verarbeitete Stress- und Traumaerlebnisse als Hintergrund haben und dann ein erneutes Stresserlebnis erfahren, welches zum dissoziativen Amnesiezustand führt. Es wird postuliert, dass in erster Linie Patienten betroffen sind, die im neuen Heimatland nicht ausreichend und ihrem Anspruch entsprechend Fuß fassen konnten. Mangelnde Sprachkenntnisse und eine nicht den Erwartungen entsprechende neue Arbeitssituation sind am ehesten als Gründe anzuführen.
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Affiliation(s)
- Angelica Staniloiu
- Physiologische Psychologie, Universität Bielefeld, Bielefeld
- Sunnybrook Health Sciences Centre, Toronto, Canada
- University of Toronto, Toronto, Canada
- University of Bucharest, Bucharest, Romania
- Oberbergklinik, Hornberg
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28
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Harrison NA, Johnston K, Corno F, Casey SJ, Friedner K, Humphreys K, Jaldow EJ, Pitkanen M, Kopelman MD. Psychogenic amnesia: syndromes, outcome, and patterns of retrograde amnesia. Brain 2017; 140:2498-2510. [DOI: 10.1093/brain/awx186] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 06/15/2017] [Indexed: 11/13/2022] Open
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29
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Dissociative amnesia: Disproportionate retrograde amnesia, stressful experiences and neurological circumstances. Rev Neurol (Paris) 2017; 173:516-520. [DOI: 10.1016/j.neurol.2017.07.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 07/10/2017] [Accepted: 07/12/2017] [Indexed: 01/24/2023]
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30
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Abstract
Retrograde amnesia is described as condition which can occur after direct brain damage, but which occurs more frequently as a result of a psychiatric illness. In order to understand the amnesic condition, content-based divisions of memory are defined. The measurement of retrograde memory is discussed and the dichotomy between "organic" and "psychogenic" retrograde amnesia is questioned. Briefly, brain damage-related etiologies of retrograde amnesia are mentioned. The major portion of the review is devoted to dissociative amnesia (also named psychogenic or functional amnesia) and to the discussion of an overlap between psychogenic and "brain organic" forms of amnesia. The "inability of access hypothesis" is proposed to account for most of both the organic and psychogenic (dissociative) patients with primarily retrograde amnesia. Questions such as why recovery from retrograde amnesia can occur in retrograde (dissociative) amnesia, and why long-term new learning of episodic-autobiographic episodes is possible, are addressed. It is concluded that research on retrograde amnesia research is still in its infancy, as the neural correlates of memory storage are still unknown. It is argued that the recollection of episodic-autobiographic episodes most likely involves frontotemporal regions of the right hemisphere, a region which appears to be hypometabolic in patients with dissociative amnesia.
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Affiliation(s)
- H J Markowitsch
- Department of Physiological Psychology, University of Bielefeld, Bielefeld, Germany.
| | - A Staniloiu
- Department of Physiological Psychology, University of Bielefeld, Bielefeld, Germany; Department of Psychiatry, Sunnybrook Hospital, Toronto, ON, Canada
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31
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Wang JK, Hu LY, Lee YT. The lesson for us in a bipolar disorder patient comorbid with dissociative amnesia. Aust N Z J Psychiatry 2015; 49:1227-8. [PMID: 26238383 DOI: 10.1177/0004867415598012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Jiunn-kae Wang
- Department of Psychiatry, Shuang-Ho Hospital, Taipei Medical University, New Taipei City, Taiwan
| | - Li-Yu Hu
- Department of Psychiatry, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan
| | - Yao-Tung Lee
- Department of Psychiatry, Shuang-Ho Hospital, Taipei Medical University, New Taipei City, Taiwan
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32
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Stone J, Pal S, Blackburn D, Reuber M, Thekkumpurath P, Carson A. Functional (Psychogenic) Cognitive Disorders: A Perspective from the Neurology Clinic. J Alzheimers Dis 2015; 48 Suppl 1:S5-S17. [DOI: 10.3233/jad-150430] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Jon Stone
- Centre for Clinical Brain Sciences, University of Edinburgh, Western General Hospital, Crewe Rd, Edinburgh, UK
| | - Suvankar Pal
- Centre for Clinical Brain Sciences, University of Edinburgh, Western General Hospital, Crewe Rd, Edinburgh, UK
- Anne Rowling Regenerative Neurology Clinic, University of Edinburgh, UK
| | - Daniel Blackburn
- Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Markus Reuber
- Department of Neuroscience, University of Sheffield, Sheffield, UK
| | - Parvez Thekkumpurath
- Centre for Clinical Brain Sciences, University of Edinburgh, Western General Hospital, Crewe Rd, Edinburgh, UK
| | - Alan Carson
- Centre for Clinical Brain Sciences, University of Edinburgh, Western General Hospital, Crewe Rd, Edinburgh, UK
- Department of Rehabilitation Medicine and Department of Clinical Neurosciences, NHS Lothian, Edinburgh, UK
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33
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FDG-PET Contributions to the Pathophysiology of Memory Impairment. Neuropsychol Rev 2015; 25:326-55. [PMID: 26319237 DOI: 10.1007/s11065-015-9297-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 08/04/2015] [Indexed: 10/23/2022]
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34
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Felician O, Tramoni E, Bartolomei F. Transient epileptic amnesia: Update on a slowly emerging epileptic syndrome. Rev Neurol (Paris) 2015; 171:289-97. [DOI: 10.1016/j.neurol.2014.11.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Accepted: 11/11/2014] [Indexed: 11/30/2022]
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35
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Helmes E, Brown JM, Elliott L. A case of dissociative fugue and general amnesia with an 11-year follow-up. J Trauma Dissociation 2015; 16:100-13. [PMID: 25365262 DOI: 10.1080/15299732.2014.969469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Dissociative fugue refers to loss of personal identity, often with the associated loss of memories of events (general amnesia). Here we report on the psychological assessment of a 54-year-old woman with loss of identity and memories of 33 years of her life attributed to dissociative fugue, along with a follow-up 11 years later. Significant levels of personal injury and stress preceded the onset of the amnesia. A detailed neuropsychological assessment was completed at a university psychology clinic, with a follow-up assessment there about 11 years later with an intent to determine whether changes in her cognitive status were associated with better recall of her life and with her emotional state. Psychomotor slowing and low scores on measures of attention and both verbal and visual memory were present initially, along with significant psychological distress associated with the diagnosis of posttraumatic stress disorder. Although memories of her life had not returned by follow-up, distress had abated and memory test scores had improved. The passage of time and a better emotional state did not lead to recovery of lost memories. Contrary to expectations, performance on tests of executive functions was good on both occasions. Multiple stressful events are attributed as having a role in maintaining the loss of memories.
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Affiliation(s)
- Edward Helmes
- a Department of Psychology , James Cook University , Townsville , Australia
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36
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Daniels JK, Gaebler M, Lamke JP, Walter H. Grey matter alterations in patients with depersonalization disorder: a voxel-based morphometry study. J Psychiatry Neurosci 2015; 40:19-27. [PMID: 25285875 PMCID: PMC4275327 DOI: 10.1503/jpn.130284] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND To our knowledge, no whole brain investigation of morphological aberrations in dissociative disorder is available to date. Previous region-of-interest studies focused exclusively on amygdalar, hippocampal and parahippocampal grey matter volumes and did not include patients with depersonalization disorder (DPD). We therefore carried out an explorative whole brain study on structural brain aberrations in patients with DPD. METHODS We acquired whole brain, structural MRI data for patients with DPD and healthy controls. Voxel-based morphometry was carried out to test for group differences, and correlations with symptom severity scores were computed for grey matter volume. RESULTS Our study included 25 patients with DPD and 23 controls. Patients exhibited volume reductions in the right caudate, right thalamus and right cuneus as well as volume increases in the left dorsomedial prefrontal cortex and right somatosensory region that are not a direct function of anxiety or depression symptoms. LIMITATIONS To ensure ecological validity, we included patients with comorbid disorders and patients taking psychotropic medication. CONCLUSION The results of this first whole brain investigation of grey matter volume in patients with a dissociative disorder identified structural alterations in regions subserving the emergence of conscious perception. It remains unknown if these alterations are best understood as risk factors for or results of the disorder.
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Affiliation(s)
- Judith K. Daniels
- Correspondence to: J.K. Daniels, Clinic for Psychosomatic Medicine and Psychotherapy, Otto-von-Guericke University, Magdeburg, Germany;
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37
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Ford JD, Gómez JM. The relationship of psychological trauma and dissociative and posttraumatic stress disorders to nonsuicidal self-injury and suicidality: a review. J Trauma Dissociation 2015; 16:232-71. [PMID: 25758363 DOI: 10.1080/15299732.2015.989563] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
We reviewed research on the relationship between (a) exposure to psychological trauma and (b) nonsuicidal self-injury (NSSI) and suicidality (suicidal ideation [SI] and suicide attempts [SA]) in individuals with dissociative disorders and posttraumatic stress disorder (PTSD). The review provides a context for the special issue of the Journal of Trauma & Dissociation on these topics. Exposure to childhood sexual abuse is the most consistent traumatic antecedent of self-harm, although traumatic violence in childhood (particularly physical abuse) and adulthood (particularly domestic violence) and exposure to multiple types of traumatic stressors also are associated with NSSI and SI/SA. Dissociative disorders and PTSD are consistently associated with increased NSSI and SA/SI. There is preliminary cross-sectional evidence that dissociation and posttraumatic stress disorders may mediate the relationship between psychological trauma and NSSI and SI/SA. Research on emotion dysregulation as a potential cross-cutting mechanism linking dissociation, PTSD, and self-harm is also reviewed. We conclude with a discussion of implications for clinical practice and future directions for scientific research.
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Affiliation(s)
- Julian D Ford
- a Department of Psychiatry , University of Connecticut School of Medicine , Farmington , Connecticut , USA
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38
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Kaphan E, Barbeau E, Royère ML, Guedj E, Pelletier J, Ali Chérif A. Ganser-like syndrome after loss of psychic self-activation syndrome: psychogenic or organic? Arch Clin Neuropsychol 2014; 29:715-23. [PMID: 25280796 DOI: 10.1093/arclin/acu046] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Very few data are available on the long-term changes in the cognitive abilities of patients with loss of psychic self-activation syndrome (LPSAS). Here, we present a 25-year follow-up study on a case of LPSAS resulting from bilateral pallidal lesions caused by carbon monoxide intoxication. Typical signs of LPSAS were observed, showing no changes in severity, but Ganser syndrome (GS) gradually developed and worsened during the follow-up period. GS is generally assumed to be a psychogenic syndrome, but an organic etiology has been suspected by the authors of several case reports. Here, atypical features of GS plead against the independence of GS and LPSAS. DaTSCAN and brain 18FDG-PET were performed. Since left hippocampal hypometabolism has been previously described in patients with functional amnesia, it is possible that long periods of mental inactivity may have psychological consequences, but the atypical features of GS also suggest that an organic mechanism may be involved.
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Affiliation(s)
- Elsa Kaphan
- Service de Neurologie, Pôle de Neurosciences cliniques, AP-HM Timone, Marseille 13005, France
| | - Emmanuel Barbeau
- Service de Neurologie et Neuropsychologie, Faculté de Médecine, Pôle de Neurosciences cliniques, AP-HM Timone and LNN INSERM U751, Marseille 13005, France
| | - Marie L Royère
- Service de Neurologie et Neuropsychologie, Faculté de Médecine, Pôle de Neurosciences cliniques, AP-HM Timone and LNN INSERM U751, Marseille 13005, France
| | - Eric Guedj
- Aix-Marseille Université, CNRS UMR7289, INT, & CERIMED, Marseille13005, France
| | - Jean Pelletier
- Service de Neurologie, Pôle de Neurosciences cliniques, AP-HM Timone, Marseille 13005, France
| | - André Ali Chérif
- Service de Neurologie, Pôle de Neurosciences Cliniques, AP-HM Timone and INCM, UMR 6193, CNRS Aix-Marseille, Aix-Marseille Université, Marseille13005, France
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Abstract
Dissociative amnesia is one of the most enigmatic and controversial psychiatric disorders. In the past two decades, interest in the understanding of its pathophysiology has surged. In this report, we review new data about the epidemiology, neurobiology, and neuroimaging of dissociative amnesia and show how advances in memory research and neurobiology of dissociation inform proposed pathogenetic models of the disorder. Dissociative amnesia is characterised by functional impairment. Additionally, preliminary data suggest that affected people have an increased and possibly underestimated suicide risk. The prevalence of dissociative amnesia differs substantially across countries and populations. Symptoms and disease course also vary, indicating a possibly heterogeneous disorder. The accompanying clinical features differ across cultural groups. Most dissociative amnesias are retrograde, with memory impairments mainly involving the episodic-autobiographical memory domain. Anterograde dissociative amnesia occurring without significant retrograde memory impairments is rare. Functional neuroimaging studies of dissociative amnesia with prevailing retrograde memory impairments show changes in the network that subserves autobiographical memory. At present, no evidence-based treatments are available for dissociative amnesia and no broad framework exists for its rehabilitation. Further research is needed into its neurobiology, course, treatment options, and strategies to improve differential diagnoses.
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40
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Denkova EJ, Manning L. FMRI contributions to addressing autobiographical memory impairment in temporal lobe pathology. World J Radiol 2014; 6:93-105. [PMID: 24778771 PMCID: PMC4000613 DOI: 10.4329/wjr.v6.i4.93] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 02/11/2014] [Accepted: 03/17/2014] [Indexed: 02/06/2023] Open
Abstract
Episodic autobiographical memory (AM) allows one, through the recollection of sensory-perceptual details, thoughts and feelings, to become aware of an event as belonging to one’s own past as well as being able to project into one’s future. Because AM provides a sense of self-continuity, contributes to the integrity of the self, and helps predicting future experiences, any deficit of AM may have debilitating consequences for everyday life functioning. Understanding AM failure and the underlying neural mechanisms has the potential to shed light on brain reorganization mechanisms and engagement of compensatory processes. Functional magnetic resonance imaging (fMRI) provides the most promising imaging method to tackle these issues. We reviewed evidence from the few studies that used fMRI to investigate the functionality of the residual tissue, the neural reorganization and compensatory mechanisms in patients with neurological conditions due to impaired medial temporal lobe. Overall, these studies highlight the importance of the left hippocampus, which when atrophied and not functional leads to AM deficits but its residual functionality may support relatively normal AM recollection. When damaged hippocampal tissue is not functional, other brain regions (e.g., the medial prefrontal cortex) may be involved to compensate impairment, but they appear generally ineffective to support detailed episodic recollection.
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van der Kruijs SJM, Bodde NMG, Carrette E, Lazeron RHC, Vonck KEJ, Boon PAJM, Langereis GR, Cluitmans PJM, Feijs LMG, Hofman PAM, Backes WH, Jansen JFA, Aldenkamp AP. Neurophysiological correlates of dissociative symptoms. J Neurol Neurosurg Psychiatry 2014; 85:174-9. [PMID: 23175855 DOI: 10.1136/jnnp-2012-302905] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE Dissociation is a mental process with psychological and somatoform manifestations, which is closely related to hypnotic suggestibility and essentially shows the ability to obtain distance from reality. An increased tendency to dissociate is a frequently reported characteristic of patients with functional neurological symptoms and syndromes (FNSS), which account for a substantial part of all neurological admissions. This review aims to investigate what heart rate variability (HRV), EEG and neuroimaging data (MRI) reveal about the nature of dissociation and related conditions. METHODS Studies reporting HRV, EEG and neuroimaging data related to hypnosis, dissociation and FNSS were identified by searching the electronic databases Pubmed and ScienceDirect. RESULTS The majority of the identified studies concerned the physiological characteristics of hypnosis; relatively few investigations on dissociation related FNSS were identified. General findings were increased parasympathetic functioning during hypnosis (as measured by HRV), and lower HRV in patients with FNSS. The large variety of EEG and functional MRI investigations with diverse results challenges definite conclusions, but evidence suggests that subcortical as well as (pre)frontal regions serve emotion regulation in dissociative conditions. Functional connectivity analyses suggest the presence of altered brain networks in patients with FNSS, in which limbic areas have an increased influence on motor preparatory regions. CONCLUSIONS HRV, EEG and (functional) MRI are sensitive methods to detect physiological changes related to dissociation and dissociative disorders such as FNSS, and can possibly provide more information about their aetiology. The use of such measures could eventually provide biomarkers for earlier identification of patients at risk and appropriate treatment of dissociative conditions.
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42
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Magnin E, Thomas-Antérion C, Sylvestre G, Haffen S, Magnin-Feysot V, Rumbach L. Conversion, dissociative amnesia, and Ganser syndrome in a case of "chameleon" syndrome: anatomo-functional findings. Neurocase 2014; 20:27-36. [PMID: 23075263 DOI: 10.1080/13554794.2012.732081] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The term "chameleon" was first used in the seventeenth century by Sydenham to describe a patient with a protean semiology. We report a single case of "chameleon" syndrome that challenges the current international criteria for somatoform disorders, dissociative amnesia, and Ganser syndrome. The florid symptoms were as follows: anterograde and retrograde amnesia (including semantic, episodic, and procedural deficits), loss of identity, atypical neuropsychological impairment (approximate answers), left sensitive and motor deficit, and left pseudochoreoathetosis movement disorders. Additional behavioral disorders included the following: anxiety, clouded consciousness, hallucinations, and "belle indifference". A single photon emission computed tomography examination showed bilateral temporal, frontal and a right caudate (in the head of the caudate nucleus) hypoperfusion concordant with a common mechanism of repression in these disorders.
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Affiliation(s)
- Eloi Magnin
- a Department of Neurology , University Hospital of Besançon , Besançon , France
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Nardo D, Högberg G, Lanius RA, Jacobsson H, Jonsson C, Hällström T, Pagani M. Gray matter volume alterations related to trait dissociation in PTSD and traumatized controls. Acta Psychiatr Scand 2013; 128:222-33. [PMID: 23113800 DOI: 10.1111/acps.12026] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/17/2012] [Indexed: 11/30/2022]
Abstract
OBJECTIVE This study used voxel-based morphometry (VBM) to investigate brain structural alterations related to trait dissociation and its relationship with post-traumatic stress disorder (PTSD). METHOD Thirty-two subjects either developing (N = 15) or non-developing (N = 17) PTSD underwent MRI scanning and were assessed with the Dissociative Experience Scale (DES), subscales for pathological (DES-T) and non-pathological trait (DES-A) dissociation, and other clinical measures. Gray matter volume (GMV) was analyzed using VBM as implemented in SPM. PTSD and non-PTSD subjects were compared to assess brain alterations related to PTSD pathology, whereas correlation analyses between dissociation measures and GMV were performed on the whole sample (N = 32), irrespective of PTSD diagnosis, to identify alterations related to trait dissociation. RESULTS As compared to traumatized controls, PTSD subjects showed reduced GMV in the prefrontal cortex, hippocampus and lingual gyrus. Correlations with dissociation measures (DES, DES-T, and DES-A) consistently showed increased GMV in the medial and lateral prefrontal, orbitofrontal, parahippocampal, temporal polar, and inferior parietal cortices. CONCLUSION PTSD and dissociation seem to be associated with opposite volumetric patterns in the prefrontal cortex. Trait dissociation appears to involve increased GMV in prefrontal, paralimbic, and parietal cortices, with negligible differences between pathological and non-pathological dissociation.
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Affiliation(s)
- D Nardo
- Neuroimaging Laboratory, Santa Lucia Foundation, Rome, Italy.
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Egocentric virtual maze learning in adult survivors of childhood abuse with dissociative disorders: evidence from functional magnetic resonance imaging. Psychiatry Res 2013; 212:116-24. [PMID: 23522878 DOI: 10.1016/j.pscychresns.2012.11.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2011] [Revised: 11/01/2012] [Accepted: 11/02/2012] [Indexed: 11/21/2022]
Abstract
Present neuroimaging findings suggest two subtypes of trauma response, one characterized predominantly by hyperarousal and intrusions, and the other primarily by dissociative symptoms. The neural underpinnings of these two subtypes need to be better defined. Fourteen women with childhood abuse and the current diagnosis of dissociative amnesia or dissociative identity disorder but without posttraumatic stress disorder (PTSD) and 14 matched healthy comparison subjects underwent functional magnetic resonance imaging (fMRI) while finding their way in a virtual maze. The virtual maze presented a first-person view (egocentric), lacked any topographical landmarks and could be learned only by using egocentric navigation strategies. Participants with dissociative disorders (DD) were not impaired in learning the virtual maze when compared with controls, and showed a similar, although weaker, pattern of activity changes during egocentric learning when compared with controls. Stronger dissociative disorder severity of participants with DD was related to better virtual maze performance, and to stronger activity increase within the cingulate gyrus and the precuneus. Our results add to the present knowledge of preserved attentional and visuospatial mnemonic functioning in individuals with DD.
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Markowitsch HJ. Memory and self-neuroscientific landscapes. ISRN NEUROSCIENCE 2013; 2013:176027. [PMID: 24967303 PMCID: PMC4045540 DOI: 10.1155/2013/176027] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Accepted: 04/22/2013] [Indexed: 02/07/2023]
Abstract
Relations between memory and the self are framed from a number of perspectives-developmental aspects, forms of memory, interrelations between memory and the brain, and interactions between the environment and memory. The self is seen as dividable into more rudimentary and more advanced aspects. Special emphasis is laid on memory systems and within them on episodic autobiographical memory which is seen as a pure human form of memory that is dependent on a proper ontogenetic development and shaped by the social environment, including culture. Self and episodic autobiographical memory are seen as interlocked in their development and later manifestation. Aside from content-based aspects of memory, time-based aspects are seen along two lines-the division between short-term and long-term memory and anterograde-future-oriented-and retrograde-past-oriented memory. The state dependency of episodic autobiographical is stressed and implications of it-for example, with respect to the occurrence of false memories and forensic aspects-are outlined. For the brain level, structural networks for encoding, consolidation, storage, and retrieval are discussed both by referring to patient data and to data obtained in normal participants with functional brain imaging methods. It is elaborated why descriptions from patients with functional or dissociative amnesia are particularly apt to demonstrate the facets in which memory, self, and personal temporality are interwoven.
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Affiliation(s)
- Hans J. Markowitsch
- Physiological Psychology, University of Bielefeld, Universitaetsstraße 25, 33615 Bielefeld, Germany
- Center of Excellence “Cognitive Interaction Technology” (CITEC), University of Bielefeld, 33615 Bielefeld, Germany
- Hanse Institute of Advanced Science, P. O. Box 1344, 27733 Delmenhorst, Germany
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Pause BM, Zlomuzica A, Kinugawa K, Mariani J, Pietrowsky R, Dere E. Perspectives on episodic-like and episodic memory. Front Behav Neurosci 2013; 7:33. [PMID: 23616754 PMCID: PMC3629296 DOI: 10.3389/fnbeh.2013.00033] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Accepted: 04/06/2013] [Indexed: 11/30/2022] Open
Abstract
Episodic memory refers to the conscious recollection of a personal experience that contains information on what has happened and also where and when it happened. Recollection from episodic memory also implies a kind of first-person subjectivity that has been termed autonoetic consciousness. Episodic memory is extremely sensitive to cerebral aging and neurodegenerative diseases. In Alzheimer’s disease deficits in episodic memory function are among the first cognitive symptoms observed. Furthermore, impaired episodic memory function is also observed in a variety of other neuropsychiatric diseases including dissociative disorders, schizophrenia, and Parkinson disease. Unfortunately, it is quite difficult to induce and measure episodic memories in the laboratory and it is even more difficult to measure it in clinical populations. Presently, the tests used to assess episodic memory function do not comply with even down-sized definitions of episodic-like memory as a memory for what happened, where, and when. They also require sophisticated verbal competences and are difficult to apply to patient populations. In this review, we will summarize the progress made in defining behavioral criteria of episodic-like memory in animals (and humans) as well as the perspectives in developing novel tests of human episodic memory which can also account for phenomenological aspects of episodic memory such as autonoetic awareness. We will also define basic behavioral, procedural, and phenomenological criteria which might be helpful for the development of a valid and reliable clinical test of human episodic memory.
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Affiliation(s)
- Bettina M Pause
- Institute of Experimental Psychology, University of Düsseldorf Düsseldorf, Germany
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Abstract
Transient amnesic syndromes are striking clinical phenomena that are commonly encountered by physicians in acute medical settings. Diagnosis of such syndromes can be challenging, and their causes have been debated for over 50 years. Critical clinical distinctions, such as between transient global amnesia (TGA) and transient epileptic amnesia (TEA), as well as important clues to the underlying pathophysiology, have recently been revealed. TGA is characterized by the sudden onset of a profound anterograde and retrograde amnesia that lasts for up to 24 h, with neuroimaging after an acute TGA event showing transient perturbation of specific hippocampal circuits that are involved in memory processing. Some cases of transient amnesia are attributable to focal seizure activity and are termed TEA, which has a clinical presentation similar to that of TGA, but can be distinguished from the latter by the brevity and frequency of amnesic attacks. Moreover, TEA carries a risk of persistent memory impairment that can be mistaken for dementia. Here, we summarize clinically relevant aspects of transient amnesic syndromes, giving practical recommendations for diagnosis and patient management. We describe results from imaging and epidemiological studies that have shed light on the functional anatomy and pathophysiological mechanisms underlying these conditions.
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An Interesting Case of Barbiturate Automatism and Review of Literature. Case Rep Neurol Med 2013; 2013:713065. [PMID: 24222872 PMCID: PMC3810195 DOI: 10.1155/2013/713065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Accepted: 09/11/2013] [Indexed: 11/17/2022] Open
Abstract
A 48 year old man with a diagnosis of HIV infection since 1993, on highly active anti-retro viral therapy (HAART) with stable CD4 count and undetectable viral load for years and seizure disorder presented with recurrent drowsiness. His seizures were well controlled on phenobarbitone for years. Repeated laboratory evaluation demonstrated toxic levels of phenobarbitone in his blood. A thorough clinical, psychiatric, laboratory and imaging evaluation did not reveal any obvious etiology for the recurrent barbiturate intoxication in this man. Our findings suggest the possible diagnosis of barbiturate drug automatism in this patient. Though drug automatism is a controversial entity, it merits continued attention. There are recent reports of similar phenomenon with newer sedative agents such as Zolpidem. It is important to be aware of this phenomenon as a possible explanation for recurrent intoxication with barbiturates without a clear etiology for drug overdose.
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A rare variant of dissociative amnesia: Back to the past. Kaohsiung J Med Sci 2013; 29:59-60. [DOI: 10.1016/j.kjms.2012.08.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Staniloiu A, Markowitsch HJ. Towards solving the riddle of forgetting in functional amnesia: recent advances and current opinions. Front Psychol 2012; 3:403. [PMID: 23125838 PMCID: PMC3485580 DOI: 10.3389/fpsyg.2012.00403] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Accepted: 09/27/2012] [Indexed: 01/24/2023] Open
Abstract
Remembering the past is a core feature of human beings, enabling them to maintain a sense of wholeness and identity and preparing them for the demands of the future. Forgetting operates in a dynamic neural connection with remembering, allowing the elimination of unnecessary or irrelevant information overload and decreasing interference. Stress and traumatic experiences could affect this connection, resulting in memory disturbances, such as functional amnesia. An overview of clinical, epidemiological, neuropsychological, and neurobiological aspects of functional amnesia is presented, by preponderantly resorting to own data from patients with functional amnesia. Patients were investigated medically, neuropsychologically, and neuroradiologically. A detailed report of a new case is included to illustrate the challenges posed by making an accurate differential diagnosis of functional amnesia, a condition that may encroach on the boundaries between psychiatry and neurology. Several mechanisms may play a role in "forgetting" in functional amnesia, such as retrieval impairments, consolidating defects, motivated forgetting, deficits in binding and reassembling details of the past, deficits in establishing a first person autonoetic connection with personal events, and loss of information. In a substantial number of patients, we observed a synchronization abnormality between a frontal lobe system, important for autonoetic consciousness, and a temporo-amygdalar system, important for evaluation and emotions, which provides empirical support for an underlying mechanism of dissociation (a failure of integration between cognition and emotion). This observation suggests a mnestic blockade in functional amnesia that is triggered by psychological or environmental stress and is underpinned by a stress hormone mediated synchronization abnormality during retrieval between processing of affect-laden events and fact-processing.
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Affiliation(s)
| | - Hans J. Markowitsch
- Physiological Psychology, University of BielefeldBielefeld, Germany
- Center of Excellence Cognitive Interaction Technology, University of BielefeldBielefeld, Germany
- Hanse Institute for Advanced StudyDelmenhorst, Germany
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