Semantic cognition

This groundbreaking monograph offers a mechanistic theory of therepresentation and use of semantic knowledge, integrating the strengths andovercoming many of the weaknesses of hierarchical, categorization-based approaches, similarity-based approaches, and the approach often called "theory theory." Buildingon earlier models by Geoffrey Hinton in the 1980s and David Rumelhart in the early1990s, the authors propose that performance in semantic tasks arises through thepropagation of graded signals in a system of interconnected processing units. Therepresentations used in performing these tasks are patterns of activation acrossunits, governed by weighted connections among them. Semantic knowledge is acquiredthrough the gradual adjustment of the strengths of these connections in the courseof day-to-day experience.The authors show how a simple computational model proposedby Rumelhart exhibits a progressive differentiation of conceptual knowledge, paralleling aspects of cognitive development seen in the work of Frank Keil and JeanMandler. The authors extend the model to address aspects of conceptual knowledgeacquisition in infancy, disintegration of conceptual knowledge in dementia, "basic-level" effects and their interaction with expertise, and many findingsintroduced to support the idea that semantic cognition is guided by naive, domain-specific theories.