Preserved ability to recognize keywords related to remote events in the absence of retrieval of relevant knowledge: A case of postencephalitic amnesia

• Published in: Brain and cognition 2003-02, Vol.51 (1), p.1-11
• Main Authors: Tsukiura, Takashi, Ohtake, Hiroya, Fujii, Toshikatsu, Miura, Rina, Ogawa, Tatsuji, Yamadori, Atsushi
• Format: Article
• Language: English
• Subjects: Adult and adolescent clinical studies; Amnesia; Amnesia - diagnosis; Amnesia - etiology; Autobiography as Topic; Biological and medical sciences; Cerebral Cortex - pathology; Cognition; Cues; Encephalitis, Herpes Simplex - complications; Encephalitis, Herpes Simplex - pathology; Female; Gyrus Cinguli - pathology; Hippocampal formation; Hippocampus - pathology; Humans; Life Change Events; Magnetic Resonance Imaging; Medial temporal lobe; Medical sciences; Middle Aged; Organic mental disorders. Neuropsychology; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Recognition (Psychology); Retrograde amnesia; Severity of Illness Index; Temporal Lobe - pathology; Vocabulary; Wechsler Scales
• ISSN: 0278-2626; 1090-2147
• DOI: 10.1016/S0278-2626(02)00529-8

We describe a case of severe anterograde and retrograde amnesia resulting from herpes simplex encephalitis. Magnetic resonance imaging revealed pathological changes in the bilateral hippocampi, parahippocampal gyri, fusiform gyri, medial temporal poles, posterior part of the cingulate gyri, and insula. The patient showed severe amnesia for autobiographical episodic memory in relation to events that had occurred throughout her life, but temporally graded amnesia for autobiographical semantic memory, and severe amnesia without a temporal gradient for public events and famous people. However, using a multiple-choice method, she showed a high level of accuracy when choosing keywords related to public or personal events, although this did not prompt her recollection of the events. An important indication of these results is that, even with severe retrograde amnesia, memories of past events are not completely lost. We propose that an event may be stored in a fragmented form, consisting of many components, and that normal recall of an event may require recombination or reconstruction of these components.