Trois populations ont été étudiées : des patient∙e∙s présentant un ictus amnésique idiopathique, des patients∙e∙s avec une amnésie dissociative et des personnes exposées à un trauma (les attaques du à Paris) présentant ou non un trouble de stress post-traumatique (TSPT). Ces travaux concernent la compréhension des liens entre la conscience de soi et les formes de mémoire associées au self (mémoire épisodique et autobiographique) des patients et des patientes présentant des troubles de la mémoire associés au stress. La conscience de soi permet à un individu de se connaître et de réaliser son action sur le monde. Nevertheless, despite the recent progress in the identification of the biological mechanisms underlying this disorder, the research cannot be considered as completed and further investigation is needed. As a result, current research indicates that neurobiological mechanisms at least partially explain mechanisms of dissociative amnesia. Yet, individual differences in the predisposition to the occurrence of dissociative amnesia might be an important factor in developing this disorder such as the predisposition to overreact to distressing factors. Meanwhile, the amygdalae primarily regulate the intensity of an emotional reaction to a traumatic event, and hence affect the arousal of other brain structures. Too rapid or too long secretion of stress hormones may lead to an excessive arousal of the hippocampus, which may then lead to hippocampus damage. As a result of the exposure to stress factors, stress hormones are secreted, which leads to an arousal of the hippocampus. The hip-pocampus is a very flexible structure, yet highly vulnerable. In the case of an excessive arousal, its functions become deregulated, which results in the inability to register the received stimuli. The prefrontal cortex is a structure, which integrates internal and external experience. Research on this phenomenon indicated that the main biological factors that trigger dissociative amnesia are an excessive arousal of the prefrontal cortex, hippocampus and amygdalae. Although the classification criteria of dissociative amnesia are based solely on the clinical image and do not refer to biological mechanisms, recent neurobiolo-gical studies using applied modern brain imaging techniques suggest that biological mechanisms play a crucial role in this disorder. Dissociative amnesia is defined as the retrograde memory loss in the absence of detectable structural brain damage caused by disassociation.
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