Virtual Reality for Assessment of Episodic Memory in Normal and Pathological Aging
Résumé
Memory is one of the most important cognitive functions in a person’s life. Memory is essential for recalling personal memories and for performing many everyday tasks, such as reading, playing music, returning home, and planning future actions, and, more generally, memory is crucial for interacting with the world. Determining how humans encode, store, and retrieve memories has a long scientific history, beginning with the classical research by Ebbinghaus in the late 20th century (Ebbinghaus, 1964). Since this seminal work, the large number of papers published in the domain of memory testifies that understanding memory is one of the most important challenges in cognitive neurosciences. With population growth and population aging, understanding memory failures both in the healthy elderly and in neurological and psychiatric conditions is a major societal issue. A substantial body of evidence, mainly from double dissociations observed in neuropsychological patients, has led researchers to consider memory not as a unique entity but as comprising several forms with distinct neuroanatomical substrates (Squire, 2004). With reference to long-term memory, episodic memory may be described as the conscious recollection of personal events combined with their phenomenological and spatiotemporal encoding contexts, such as recollecting one’s wedding day with all the contextual details (Tulving, 2002). Episodic memory is typically opposed to semantic memory, which is viewed as a system dedicated to the storage of facts and general decontextualized knowledge (e.g., Paris is the capital of France), including also the mental lexicon. Episodic memory was initially defined by Tulving as a memory system specialized in storing specific experiences in terms of what happened and where and when it happened (Tulving, 1972). Later, phenomenological processes were associated with the retrieval of memories (Tulving, 2002). Episodic memory is assumed to depend on the self, and involves mental time travel and a sense of reliving the original encoding context that includes autonoetic awareness (i.e., the awareness that this experience happened to oneself, is not happening now, and is part of one’s personal history).