Structure of Semantic MemorySemantic memory is our knowledge of the world and language and how it can be seen as our internal dictionary and encyclopedia together as a single entity. Since its origins, semantic memory has been compared to episodic memory. In contrast, episodic memory refers to temporary or spatial knowledge, identified in terms of personal experiences. Within these two systems there are many different models. I will discuss Eleanor Rosch's prototype approach feature comparison model, Anderson's ACT-R model, Collins and Loftus' network model, and the exemplar model. I will seek to define each of the models using characterization methods, discuss the issues within each model, and also explain which model I like the most. In 1970, Eleanor Rosch developed a prototype theory very different from the original semantics. This led to the set-theoretic approach to extensional or intentional semantics which evolved into a more definition-based model. (Rosch et al, 1976) According to Rosch, the term prototype was defined during the study "Natural Categories" in 1973 and was first defined as a stimulus. A stimulus occupies an important place in the formation of a category because it is the first stimulus associated with this category. She later redefined it as the most central member of a category. “For example, when asked to give an example of the concept of furniture, the chair is more frequently cited than, say, the stool. Prototype theory also plays a central role in linguistics, in the context of mapping phonological structure to semantics. (Rosch et al, 1976) I like his model the most because it actually deals with real life scenarios and real objects instead of dealing with representations f...... middle of paper . .....c. Erlbaum: PsychologyMcCloskey, M. & Glucksberg, S. (1979). Decision processes in verifying category membership claims: Implications for models of semantic memory. Cognitive Psychology, 11(1), 1-37.McNamara, TP and Holbrook, JB 2003. Semantic memory and priming. Textbook of psychology. 445–474.Rumelhart, DE, Hinton, GE, & McClelland, JL (1986). A general framework for parallel distributed processing. In Rumelhart, DE, & McClelland, JL and the PDP Research Group (1986) Eds. Parallel distributed processing: explorations of the microstructure of cognition. Volume 1: Foundations. MIT Press: Cambridge, MA. Tulving, E. and Schacter, D.L. (1990). Bootstrapping and human memory systems. Bum.Science, 247, 301 – 306McCloskey, ME and Glucksberg, S. (1978). Natural categories: well-defined or fuzzy sets? Memory and cognition, 6(4), 462-472