Attribute Memory Model and Behavioral Neurophysiology of Memory

Theories have been proposed to account for the multiple memory systems in the brain. Among those, the attribute theory for memory was originally proposed by Kesner. According to the theory, there are six major attributes for defining key aspects of an event. The event, once experienced, leaves its memory in the brain for short term and later becomes consolidated into a long-term memory. The attribute memory model proposes that the former type is processed by an event-based memory system and the latter type is handled by a knowledge-based memory system. The model also proposes a rule-based memory system (which is argued in this chapter as a subsystem of the knowledge-based memory system). The attribute memory model describes how different attributes recruit specific brain regions and how they interact. Computational information processes such as pattern separation and completion have also been proposed by the theory along with their associated subfields in the hippocampus. The model has always been tested in Kesner-style memory tasks, that is, goal-directed memory tasks using positive rewards. Such goal-directed tasks have provided great insights into how different memory systems and associated brain regions work in natural settings. Finding neurophysiological correlates of behavioral measures in these “freely moving” animals, however, poses a great technical challenge when one wants to record single-unit activity at the same time. As a means to continuing the Kesner-style behavioral probing in freely moving animals while analyzing single-unit activity rigorously, one needs some artful modifications in original behavioral paradigms to accommodate both behavioral and electrophysiological components. Once successfully implemented, such modifications would help physiologically test the attribute model of memory.