chapter  13
36 Pages

Environmental influences on autobiographical memory: The mnestic block syndrome

ByMATTHIAS BRAND, HANS J. MARKOWITSCH

Human beings live in an environment that changes from moment to moment. For behaving consistently with one’s own desires and beliefs, it is fundamentally important to remember the past. In addition, the feeling of having an identity or what is called “personality” is also based on past experiences and associated personal beliefs about one’s own self. Remembering events of one’s own biography, including a clear relation to time and space, has been referred to as “episodic memory” for a long time. However, the definition of episodic memory has been changed since the term was introduced by Endel Tulving three decades ago (Tulving, 1972, 1987, 1995). In recent reviews (e.g., Tulving, 2002, 2005), he emphasizes that episodic memory is the conjunction of subjective time, autonoetic consciousness, and the experiencing self and that it is not only confined to events with a clear relation to time and space, as other researchers used the term (e.g., for memory measured by laboratory tasks such as learning a word list). In addition to the core facet of autobiographical memory – that is, autobiographical-episodic memory – retrieving facts of one’s own history (e.g., the date of birth) also constitutes autobiographical memory. Nevertheless, semantic knowledge related to the biography is not stored in the episodic memory system but is part of the general knowledge system. In this contribution, we focus on autobiographicalepisodic memory and its changes linked to environmental influences. After a brief introduction in which we will summarize the brain structures most crucially involved in autobiographical-episodic memory and the processes necessary for building an episodic memory, we will review the main environmental factors influencing autobiographical-episodic memory functioning. Here, we will demonstrate that stress-related and psychogenic factors can severely compromise the ability to remember the past. We will show that even in amnesic conditions without structural brain damage, functional alterations of episodic memory-related brain circuits can be neural correlates of the patients’ amnesia.