Seminar: 4/6 - Jay McClelland
11:00 to 12:30 PM at:
Department of Psychology and Director, Center for Mind Brain and Computation
"Differentiation and Disintegration of Conceptual Knowledge: A Parallel-Distributed Processing Approach"
I will describe a model of human semantic cognition, based on the ideas of distributed representation and gradual incremental learning inherent in the Parallel-Distributed Processing (PDP) framework. The model addresses progressive differentiation of conceptual knowledge in development and progressive disintegration of conceptual knowledge in semantic dementia, a rare condition affecting the anterior and lateral portions of the temporal lobes. In addition, the model addresses primacy of basic level naming responses in development and dementia, as well as typicality, frequency, and expertise effects, providing a broad framework for understanding development, adult cognitive performance, and deterioration of conceptual knowledge in dementia. The model also addresses many of the phenomena that some have taken as supporting the idea that human semantic knowledge takes the form of naive, implicit domain theories, including category coherence effects, differential importance of different properties for different domains, and reorganization of conceptual knowledge in development. It suggests how domain specific constraints on the interpretation of new information may arise from prior experience, providing an alternative to nativist approaches to the origins of such constraints on cognition.