Electrical Signals of Memory and of the Awareness of Remembering

Learning factual information and accurately remembering specific experiences from the past are central to human intellectual and social life. These extraordinary abilities require computations on diverse sorts of information represented in the brain. Networks of neurons in the cerebral cortex are specialized for analyzing and representing such information, whereas the storage of facts and events within these networks depends fundamentally on linking multiple representational fragments together. This cross-cortical linking function is disrupted in patients with amnesia. Electrical measures of the brain in action, obtained while people perform feats of memory in laboratory settings, have been used to investigate the storage and retrieval of facts and episodes. Electrical signals associated with specific aspects of memory processing have been identified through research that constitutes part of a larger scientific endeavor aimed at understanding memory, the subjective experience of remembering that can accompany retrieval, and disorders of memory that can result from brain damage. KEYWORDS—declarative memory; priming; event-related potentials; ERPs; amnesia What happens in your brain to allow you to remember a recent acquaintance, your favorite film, your last summer vacation, or your first kiss? Contemporary investigations of such phenomena are founded on systems for classifying types of memory. Many investigators focus on the category known as declarative memory, the ability to remember prior autobiographical episodes and complex facts (Squire, 1987). This ability can be demonstrated when an individual either retrieves learned information in a recall test or discriminates learned information from new information in a recognition test. Declarative memory provides each of us with a vast but imperfect storehouse of information, and a basis for our own life story. What would constitute a comprehensive scientific understanding of declarative memory? Relevant research concerning declarative memory spans the gamut from neurobiological studies in animals to cognitive modeling in computers. A long-standing and venerable approach to exploring both the neural and the psychological underpinnings of memory is to investigate memory deficits in neurological patients. NEUROCOGNITIVE FOUNDATIONS OF