Broad Area Colloquium For AI-Geometry-Graphics-Robotics-Vision
(CS 528)
Development and Disintegration of Conceptual Knowledge
A case study in Mind, Brain, and Computation
James L, McClelland
Professor of Psychology
Director, Center for Mind, Brain and Computation
Stanford University
May 14, 2007, 4:15PM
TCSeq 200
http://graphics.stanford.edu/ba-colloquium/
Abstract
Over the past several years my collaborators and I have been developing a model of conceptual knowledge representation that attempts to address the development of conceptual knowledge in childhood, the nature of adult conceptual knowledge representation, and the disintegration of conceptual knowledge in a specific brain disorder known as .semantic dementia.. In this talk I will briefly describe some of the key phenomena in developmental psychology and cognitive neuroscience that have attracted our attention. These include differentiation of conceptual knowledge and transitory overgeneralization or .illusory correlations. on the developmental side, and a set of parallel phenomena that occur in semantic dementia: Progressive loss of differentiation, and the re-emergence of overgeneralization and illusory correlations. I will then describe a computational framework for modeling these phenomena, based on principles of parallel distributed processing and on what we know about the areas involved in semantic cognition in the brain. In discussion I will consider how the PDP approach might be seen as providing the neural instantiation of an approximation to a Bayesian model of category learning and representation.