![]() Single-case investigations, group studies and various forms of neuroimaging can all contribute to the resolution of these controversies. Theories of retrograde amnesia have encompassed storage versus access disruption, physiological processes of 'consolidation', the progressive transformation of episodic memories into a more 'semantic' form, and multiple-trace theory. Large frontal and temporal lobe lesions have been postulated as critical in producing retrograde amnesia. ![]() However, the associations of different types of retrograde amnesia are also important, and clarification of these issues is confounded by the fact that retrograde amnesia seems to be particularly vulnerable to psychogenic factors. Within retrograde amnesia, there are various dissociations which have been claimed-for example, between the more autobiographical (episodic) and more semantic components of memory. The severity of retrograde amnesia is not well correlated with that of anterograde amnesia, and there can be disproportionate impairments of either. Retrograde amnesia in neurological disorders is a perplexing and fascinating research topic. The loss of episodic memories in retrograde amnesia: single-case and group studies. After 3-6 months, the fugue patients had improved to normal scores for facts The pattern of autobiographical memory loss differed between the psychogenic groups: fugue cases showed a severe and uniform loss of memories for both facts and events across all time periods, whereas the two focal retrograde amnesia groups showed a 'reversed' temporal gradient with relative sparing of recent memories. However, clinical depression, family/relationship problems, financial/employment problems, and failure to recognize the family were also statistically more common in that group. As anticipated, loss of the sense of personal identity was confined to the psychogenic group. While neurological cases were characterized by relevant neurological symptoms, a history of a past head injury was actually more common in our psychogenic cases (P = 0.012), perhaps reflecting a 'learning episode' predisposing to later psychological amnesia. ![]() We found that our patients with psychogenic memory loss fell into four distinct groups, which we categorized as: (i) fugue state (ii) fugue-to-focal retrograde amnesia (iii) psychogenic focal retrograde amnesia following a minor neurological episode and (iv) patients with gaps in their memories. In particular, we examined the pattern of retrograde amnesia on an assessment of autobiographical memory (the Autobiographical Memory Interview). In the present study, we reviewed the case records and neuropsychological findings in 53 psychogenic amnesia cases (ratio of 3:1, males:females), in comparison with 21 consecutively recruited neurological memory-disordered patients and 14 healthy control subjects. Consequently, the literature on psychogenic amnesia is somewhat fragmented and offers little prognostic value for individual patients. There are very few case series of patients with acute psychogenic memory loss (also known as dissociative/functional amnesia), and still fewer studies of outcome, or comparisons with neurological memory-disordered patients. Harrison, Neil A Johnston, Kate Corno, Federica Casey, Sarah J Friedner, Kimberley Humphreys, Kate Jaldow, Eli J Pitkanen, Mervi Kopelman, Michael D Psychogenic amnesia: syndromes, outcome, and patterns of retrograde amnesia. 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. It is concluded that research on retrograde amnesia research is still in its infancy, as the neural correlates of memory storage are still unknown. 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. The "inability of access hypothesis" is proposed to account for most of both the organic and psychogenic (dissociative) patients with primarily retrograde amnesia. 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. Briefly, brain damage-related etiologies of retrograde amnesia are mentioned. The measurement of retrograde memory is discussed and the dichotomy between "organic" and "psychogenic" retrograde amnesia is questioned. In order to understand the amnesic condition, content-based divisions of memory are defined. 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. Functional (dissociative) retrograde amnesia.
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