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Hans J. Markowitsch - One of the best experts on this subject based on the ideXlab platform.
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Memory, Time and Autonoetic Consciousness
Procedia - Social and Behavioral Sciences, 2014Co-Authors: Hans J. Markowitsch, Angelica StaniloiuAbstract:Abstract Memory and time have multifaceted links. Along the time axis, memory is divided into short- and long-term memory. Another popular time-dependent distinction is between new and old memories and anterograde and retrograde memory impairments, respectively. Time-embedment characterizes the processing of mnemonic information, which encompasses the stages of registration, encoding, consolidation, and storage. Along the content axis, memory is partitioned into five long-term memory systems (procedural, priming, perceptual, semantic, and episodic), which are regarded to build up on each other from both a phylogenetic and ontogenetic perspective. These memory systems are accompanied by different niveaus of self and levels of consciousness. Among these long-term memory systems, the episodic memory system holds a special connection with time, which we aim to detail. In 2005, Tulving defined the episodic memory system as the conjunction of subjective time, autonoetic consciousness, and the experiencing self. Drawing on this last definition of the episodic memory, which lays an emphasis on the linkage to the self, Markowitsch has subsequently promoted the use of the construct “episodic-autobiographical” memory system. The episodic-autobiographical memory system features mental time travelling, an essential property that enables one individual to flexibly travel in subjective time in his/her past and, in addition, to flexibly project him/herself in the future. This property provides a “glue” for the self, supporting a coherent view of one's own person. According to Tulving and Markowitsch, it is unlikely that non-human animals possess the capacity for mental time travelling and the ability to “look into future” (“proscopy”). Furthermore, Tulving and Markowitsch had proposed that the ability for mental time travelling is dependent on age and intellect. Subsequent studies have confirmed that mental time travelling is one of the last features of the episodic- autobiographical memory system that achieves full functionality in humans and is the first one to be afflicted by old age, Amnesia or neurodegenerative dementias (e.g., Alzheimer's dementia). At the brain level, the emergence of the capacity for mental time travelling is accompanied by ample structural and functional reorganization of elements of the brain networks supporting episodic-autobiographical memory, autonoetic consciousness, and self-referential processing. In human beings, damage to certain brain regions may alter the sense and consciousness of time in quite different ways. Herein, we have the goal to review changes in time perception and consciousness of time, which accompany different forms of Amnesia. Patients with anterograde Amnesia manifest an inability to consciously acquire new information for long-term storage and as a consequence are often “stuck in time”. ‘Chronotaraxis’ may accompany certain forms of preponderantly anterograde Amnesia, as we aim to exemplify by drawing upon own cases, which were investigated medically, neuropsychologically, and with neuroimaging methods. Patients with retrograde Amnesia manifest an inability to consciously retrieve already stored old mnemonic information, usually from the episodic-autobiographical memory domain. They lack the capacity to “ecphorize” old memories. Interestingly, the memory impairments are very similar in the patients with focal traumatic brain injuries and in those with Psychogenic forms of Amnesia: The patients are unable to engage in mental time traveling into their past. In addition, they show an impaired ability to imagine future personal events, being as a consequence trapped in a “noetic existence”. In Psychogenic Amnesia with pronounced retrograde memory impairments, we found (via functional neuroimaging) evidence of defective synchronization during retrieval between processing of affectively loaded personal events (that is presumed to preponderantly engage the right hemisphere) and fact-based processing (that is considered to preferentially recruit the left hemisphere). These data are relevant in the light of studies pointing to a right hemisphere bias for higher forms of consciousness. We conjecture that this synchronization abnormality not only leads to a memory blockade, but also to shrinkage of mental time traveling and loss of autonoetic consciousness in Psychogenic or functional amnesic conditions.
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Psychogenic Amnesia--a malady of the constricted self.
Consciousness and cognition, 2010Co-Authors: Angelica Staniloiu, Hans J. Markowitsch, Matthias BrandAbstract:Autobiographical–episodic memory is the conjunction of subjective time, autonoetic consciousness and the experiencing self. Understanding the neural correlates of autobiographical–episodic memory might therefore be essential for shedding light on the neurobiology underlying the experience of being an autonoetic self. In this contribution we illustrate the intimate relationship between autobiographical–episodic memory and self by reviewing the clinical and neuropsychological features and brain functional imaging correlates of Psychogenic Amnesia – a condition that is usually characterized by severely impaired retrograde memory functioning, in absence of structural brain damage as detected by standard imaging. We demonstrate that in this disorder the autobiographical–episodic memory deficits do not exist in isolation, but occur with impairments of the autonoetic self-consciousness, emotional processing, and theory of mind or executive functions. Furthermore functional and metabolic brain alterations involving regions that are agreed upon to exert crucial roles in memory processes were frequently found to accompany the Psychogenic memory “loss”.
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emotion and consciousness in adolescent Psychogenic Amnesia
Journal of Neuropsychology, 2007Co-Authors: Nadine Reinhold, Hans J. MarkowitschAbstract:Psychogenic Amnesia is characterized by an impaired retrieval process of stored information, while the acquisition of new information is conserved. In addition, patients with this condition may display a state of belle indifference towards their own situation and may manifest deficits in emotional processing. So far, these conditions were noted cursorily in previous case descriptions, but have not been investigated thoroughly. We report data on two female juvenile patients that were examined with neuropsychological, including remote memory tests. No impairments in cognitive or anterograde mnestic functions but, as expected, severe disturbances in remote memory tests were found. Additionally, we administered tests to assess basic and higher emotional processing functions. Both patients showed evidence of impaired higher and, though to a lesser extent, basic emotional processing skills. Finally, we discuss the contribution of (self-)consiousness, the current emotional state and emotional processing skills as possible factors, maintaining the condition of Psychogenic Amnesia.
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massive and persistent anterograde Amnesia in the absence of detectable brain damage anterograde Psychogenic Amnesia or gross reduction in sustained effort
Journal of Clinical and Experimental Neuropsychology, 1997Co-Authors: Josef Kessler, Hans J. Markowitsch, Michael Huber, Elke Kalbe, Gerald Weberluxenburger, Peter KockAbstract:The case of a young patient with severe and persistent anterograde Amnesia of no known cause is reported. Anterograde Amnesia arose within a 1-month period and has persisted for more than 1 year. Although a wide variety of neurological and neuroradiological assessments were completed (EEG, evoked potential recordings, Doppler sonography, MRI, PET), no evidence of brain damage was detected. Neuropsychologically, the patient was of high intelligence, had average to above-average short-term memory, and normal retrograde memory abilities, but severe and persistent anterograde Amnesia in both verbal and nonverbal domains. Furthermore, he demonstrated grossly reduced long-term concentration. It is likely that a complex chain of interacting variables can produce a syndrome that appears phenomenologically as anterograde Amnesia without organically measurable correlates.
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Impaired episodic memory retrieval in a case of probable Psychogenic Amnesia
Psychiatry research, 1997Co-Authors: Hans J. Markowitsch, Pasquale Calabrese, Gereon R. Fink, H. F. Durwen, Josef Kessler, Charlotte Harting, Matthias König, E.b. Mirzaian, Wolf-dieter Heiss, Lothar HeuserAbstract:Abstract A patient with severe, selective retrograde Amnesia for personal material, diagnosed as probable Psychogenic Amnesia, was investigated intensively neuropsychologically with cranial computed tomography (CCT), magnetic resonance imaging (MRI), and single photon emission tomography (SPECT). The patient was of average intelligence and memory with no anterograde Amnesia. No evidence for structural brain damage was detected in CCT and MRI. SPECT, performed about 3 weeks after the onset of symptoms, demonstrated reduced perfusion in right temporal and frontal areas, that is, in areas which have been suggested as critical for episodic memory retrieval. To study episodic memory retrieval, positron-emission-tomography (PET) bloodflow (rCBF) measurements were performed 6 months after the onset of symptoms. During episodic memory retrieval bilateral neuronal activations were observed in the precuneus, the lateral parietal and the right dorsolateral and polar prefrontal cortex. Compared to the results of previous functional imaging studies on episodic memory retrieval, our findings suggest an underlying functional disturbance of brain areas previously demonstrated to be involved in episodic memory retrieval.
Josef Kessler - One of the best experts on this subject based on the ideXlab platform.
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massive and persistent anterograde Amnesia in the absence of detectable brain damage anterograde Psychogenic Amnesia or gross reduction in sustained effort
Journal of Clinical and Experimental Neuropsychology, 1997Co-Authors: Josef Kessler, Hans J. Markowitsch, Michael Huber, Elke Kalbe, Gerald Weberluxenburger, Peter KockAbstract:The case of a young patient with severe and persistent anterograde Amnesia of no known cause is reported. Anterograde Amnesia arose within a 1-month period and has persisted for more than 1 year. Although a wide variety of neurological and neuroradiological assessments were completed (EEG, evoked potential recordings, Doppler sonography, MRI, PET), no evidence of brain damage was detected. Neuropsychologically, the patient was of high intelligence, had average to above-average short-term memory, and normal retrograde memory abilities, but severe and persistent anterograde Amnesia in both verbal and nonverbal domains. Furthermore, he demonstrated grossly reduced long-term concentration. It is likely that a complex chain of interacting variables can produce a syndrome that appears phenomenologically as anterograde Amnesia without organically measurable correlates.
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Impaired episodic memory retrieval in a case of probable Psychogenic Amnesia
Psychiatry research, 1997Co-Authors: Hans J. Markowitsch, Pasquale Calabrese, Gereon R. Fink, H. F. Durwen, Josef Kessler, Charlotte Harting, Matthias König, E.b. Mirzaian, Wolf-dieter Heiss, Lothar HeuserAbstract:Abstract A patient with severe, selective retrograde Amnesia for personal material, diagnosed as probable Psychogenic Amnesia, was investigated intensively neuropsychologically with cranial computed tomography (CCT), magnetic resonance imaging (MRI), and single photon emission tomography (SPECT). The patient was of average intelligence and memory with no anterograde Amnesia. No evidence for structural brain damage was detected in CCT and MRI. SPECT, performed about 3 weeks after the onset of symptoms, demonstrated reduced perfusion in right temporal and frontal areas, that is, in areas which have been suggested as critical for episodic memory retrieval. To study episodic memory retrieval, positron-emission-tomography (PET) bloodflow (rCBF) measurements were performed 6 months after the onset of symptoms. During episodic memory retrieval bilateral neuronal activations were observed in the precuneus, the lateral parietal and the right dorsolateral and polar prefrontal cortex. Compared to the results of previous functional imaging studies on episodic memory retrieval, our findings suggest an underlying functional disturbance of brain areas previously demonstrated to be involved in episodic memory retrieval.
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a pet study of persistent Psychogenic Amnesia covering the whole life span
Cognitive Neuropsychiatry, 1997Co-Authors: Hans J. Markowitsch, Gereon R. Fink, Josef Kessler, Angelika Thone, Wolf-dieter HeissAbstract:A patient with ongoing Psychogenic Amnesia is described. NN lost his personal identity eight months prior to the reported investigation. All physical and neurological examinations, including magnetic resonance imaging, were unremarkable. Neuropsychological testing revealed above-average intelligence and anterograde memory abilities. No retrograde Amnesia for factual knowledge was detected. However, severe persistent Amnesia was found for personal events prior to the Psychogenic fugue (retrograde episodic Amnesia). In contrast, personal episodes subsequent to the fugue were well preserved. For NN, a PET activation study was performed during the following phases: Baseline, a rest or control state; Prefugue, during which sentences containing episodic information of NN's past prior to the fugue were presented; and Postfugue, where episodic information concerned with personal experiences following the fugue was presented. The two activation tasks both led to increases in regional cerebral blood flow in memorya...
Nadia Wager - One of the best experts on this subject based on the ideXlab platform.
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Sexual Revictimization: Double Betrayal and the Risk Associated with Dissociative Amnesia
Journal of Child Sexual Abuse, 2013Co-Authors: Nadia WagerAbstract:This study aimed to identify new treatment targets in order to develop more empirically informed initiatives to prevent sexual revictimization. A retrospective Web-based survey employing a mixed-methods design attracted a self-selecting sample of 481 community respondents, 183 of whom indicated a history of childhood sexual abuse. Seventy-four percent were females whose ages ranged from 16 to 69 years (mean = 31.2 years). Betrayal trauma referred to CSA committed by a trusted perpetrator (often caregivers). Disclosure experiences in childhood were reported though open-dialogue boxes. Double betrayal referred to high-betrayal trauma being combined with a negative response to a disclosure. This was associated with both higher incidences of prior Psychogenic Amnesia for CSA and sexual revictimization in later life. The findings have implications for educating the guardians of children about the prevalence and implications of CSA as well as the importance of early recognition and appropriate responding.
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Psychogenic Amnesia for childhood sexual abuse and risk for sexual revictimisation in both adolescence and adulthood
Sex Education, 2011Co-Authors: Nadia WagerAbstract:Psychogenic Amnesia for childhood sexual abuse and risk for sexual revictimisation in both adolescence and adulthood, Sex Education journal, DOI:10.10.80/14681811.2011.615619
Markowitsch, Hans J. - One of the best experts on this subject based on the ideXlab platform.
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Psychological causes of autobiographical Amnesia: A study of 28 cases
'Elsevier BV', 2018Co-Authors: Staniloiu Angelica, Markowitsch, Hans J., Kordon AndreasAbstract:Staniloiu A, Markowitsch HJ, Kordon A. Psychological causes of autobiographical Amnesia: A study of 28 cases. NEUROPSYCHOLOGIA. 2018;110:134-147.Autobiographical Amnesia is found in patients with focal or diffuse brain damage ("organic Amnesia"), but also without overt brain damage (at least when measured with conventional brain imaging methods). This last condition is usually named dissociative Amnesia at present, and was originally described as hysteria. Classically and traditionally, dissociative Amnesia is seen as a disorder that causes retrograde Amnesia in the autobiographical domain in the aftermath of incidents of major psychological stress or trauma. In the present study one of the probably largest published collections of patients (28) with Psychogenically caused autobiographical Amnesia, who were assessed with comprehensive neuropsychological tests, will be described and documented in order to identify variables which are central for the occurrence of dissociative Amnesia. The presented cases demonstrate that autobiographical Amnesia without direct brain damage can have very mixed clinical presentations, causes and consequences. The described cases of Psychogenic Amnesia are clustered according to a number of manifestations and features, which include a reduced effort to perform cognitively at a normal level, a forensic background, anterograde (instead of retrograde) autobiographical Amnesia, the fugue condition, concurrent somatic diseases, and their appearance in childhood and youth. It is concluded that autobiographical Amnesia of a Psychogenic origin may occur within a variety of symptom pictures. For all patients, it probably serves a protective function by offering them a mechanism to exit a life situation which appears to them unmanageable or adverse
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Retrograde episodic memory and emotion: a perspective from patients with dissociative Amnesia
'Elsevier BV', 2009Co-Authors: Reinhold Nadine, Markowitsch, Hans J.Abstract:Reinhold N, Markowitsch HJ. Retrograde episodic memory and emotion: a perspective from patients with dissociative Amnesia. Neuropsychologia. 2009;47(11):2197-2206.With his recent definition of episodic memory Tulving [Tulving, E. (2005). Episodic memory and autonoesis: Uniquely human? In H. Terrace & J. Metcalfe (Eds.), The missing link in cognition: Evolution of self-knowing consciousness (pp. 3-56). New York: Oxford University Press] claims that this memory system is uniquely human and thereby distinguishes human beings from other, even highly developed, mammals. First we will define the term episodic memory as it is currently used in neuropsychological research by specifying the three underlying concepts of subjective time, autonoetic consciousness, and the self. By doing so, we will strongly focus on retrograde episodic memory and its relation to emotion and self-referential processing. We support this relation with a discussion of autobiographical memory functions in psychiatric disorders such as dissociative Amnesia. To illustrate the connection of emotion and retrograde episodic memory we shortly present neuropsychological data of two cases of dissociative Amnesia. Both cases serve to point to the protective mechanism of a block of self-endangering memories from the episodic memory system, often described as the mnestic block syndrome. On the basis of these cases and supportive results from further cases we will conclude by pointing out similarities and differences of patients with organic and dissociative (Psychogenic) Amnesia
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Emotion and consciousness in adolescent Psychogenic Amnesia
'Wiley', 2007Co-Authors: Reinhold Nadine, Markowitsch, Hans J.Abstract:Reinhold N, Markowitsch HJ. Emotion and consciousness in adolescent Psychogenic Amnesia. JOURNAL OF NEUROPSYCHOLOGY. 2007;1(1):53-64.Psychogenic Amnesia is characterized by an impaired retrieval process of stored information, while the acquisition of new information is conserved. In addition, patients with this condition may display a state of belle indifference towards their own situation and may manifest deficits in emotional processing. So far, these conditions were noted cursorily in previous case descriptions, but have not been investigated thoroughly. We report data on two female juvenile patients that were examined with neuropsychological, including remote memory tests. No impairments in cognitive or anterograde mnestic functions but, as expected, severe disturbances in remote memory tests were found. Additionally, we administered tests to assess basic and higher emotional processing functions. Both patients showed evidence of impaired higher and, though to a lesser extent, basic emotional processing skills. Finally, we discuss the contribution of (self-)consiousness, the current emotional state and emotional processing skills as possible factors, maintaining the condition of Psychogenic Amnesia
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Functional neuroimaging in memory and memory disturbances
'Bentham Science Publishers Ltd.', 2006Co-Authors: Reinhold Nadine, Brand Matthias, Kühnel Sina, Markowitsch, Hans J.Abstract:Reinhold N, Kühnel S, Brand M, Markowitsch HJ. Functional neuroimaging in memory and memory disturbances. CURRENT MEDICAL IMAGING REVIEWS. 2006;2(1):35-57.During the past years brain imaging techniques like positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) became more and more important for gaining new insights into processes of and circuits for memory encoding and retrieval. These findings also had a great impact on a better understanding of memory dysfunctions and their underlying brain mechanisms. In the present review, data on memory dysfunctions are analyzed separately according to whether they are of an organic, or a psychiatric Psychogenic etiology. Studies examining patients with various forms of Amnesia and dementia, for whom functional brain imaging data were available, indicate early functional brain changes. These early changes differ from subsequent structural brain changes and therefore support the clinical and diagnostic use of functional brain imaging techniques in memory disturbances. Furthermore, research outcomes from patients suffering from Psychogenic Amnesias (dissociative Amnesias) and Psychogenic fugue conditions are summarized. Finally, differences and similarities between organic Amnesia and Psychogenic Amnesia are discussed with regard to the present literature and exemplified with two single cases from our lab
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Memory and brain - Neurobiological correlates of memory disturbances
'Georg Thieme Verlag KG', 2003Co-Authors: Calabrese P, Markowitsch, Hans J.Abstract:Calabrese P, Markowitsch HJ. Memory and brain - Neurobiological correlates of memory disturbances. FORTSCHRITTE DER NEUROLOGIE PSYCHIATRIE. 2003;71(4):211-219.A differentiation of memory is possible on the basis of chronological and contents-related aspects. Furthermore, it is possible to make process-specific subdivisions (encoding, transfer, consolidation, retrieval). The time-related division on the one hand refers to the general differentiation into short-term and long-term memory, and, on the other, to that between anterograde and retrograde memory ("new" and "old memory"; measured from a given time point, usually that when brain damage occurred). Anterograde memory means the successful encoding and storing of new information; retrograde the ability to retrieve successfully acquired and/or stored information. On the contents-based level, memory can be divided into five basic long-term systems-episodic memory, the knowledge system, perceptual, procedural and the priming form of memory. Neural correlates for these divisions are discussed with special emphasis of the episodic and the knowledge systems, based both on normal individuals and brain-damaged subjects. It is argued that structures of the limbic system are important for encoding of information and for its transfer into long-term memory. For this, two independent, but interacting memory circuits are proposed-one of them controlling and integrating primarily the emotional, and the other primarily the cognitive components of newly incoming information. For information storage principally neocortical structures are regarded as important and for the recall of information from the episodic and semantic memory systems the combined action of portions of prefrontal and anterior temporal regions is regarded as essential. Within this fronto-temporal agglomerate, a moderate hemispheric-specificity is assumed to exist with the right-hemispheric combination being mainly engaged in episodic memory retrieval and the left-hemispheric in that of semantic information. Evidence for this specialization comes from the results from focally brain-damaged patients as well as from that functional brain imaging in normal human subjects. Comparing results from imaging studies in memory disturbed patients with brain damage and from patients with a psychiatric diagnosis (e.g., Psychogenic Amnesia) revealed that both patient groups demonstrate comparable metabolic changes on the brain level. It can therefore be concluded that in neurological patients distinct, identifiable tissue damage is existent, while in psychiatric patients changes in the brain's biochemistry (release of stress hormones, and transmitters) constitute the physiological bases for the memory disturbances
Peter Kock - One of the best experts on this subject based on the ideXlab platform.
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massive and persistent anterograde Amnesia in the absence of detectable brain damage anterograde Psychogenic Amnesia or gross reduction in sustained effort
Journal of Clinical and Experimental Neuropsychology, 1997Co-Authors: Josef Kessler, Hans J. Markowitsch, Michael Huber, Elke Kalbe, Gerald Weberluxenburger, Peter KockAbstract:The case of a young patient with severe and persistent anterograde Amnesia of no known cause is reported. Anterograde Amnesia arose within a 1-month period and has persisted for more than 1 year. Although a wide variety of neurological and neuroradiological assessments were completed (EEG, evoked potential recordings, Doppler sonography, MRI, PET), no evidence of brain damage was detected. Neuropsychologically, the patient was of high intelligence, had average to above-average short-term memory, and normal retrograde memory abilities, but severe and persistent anterograde Amnesia in both verbal and nonverbal domains. Furthermore, he demonstrated grossly reduced long-term concentration. It is likely that a complex chain of interacting variables can produce a syndrome that appears phenomenologically as anterograde Amnesia without organically measurable correlates.