Cognitive Science 35 (2011) 1–33 Copyright ! 2010 Cognitive Science Society, Inc. All rights reserved. ISSN: 0364-0213 print / 1551-6709 online DOI: 10.1111/j.1551-6709.2010.01142.x The AHA! Experience: Creativity Through Emergent Binding in Neural Networks Paul Thagard, Terrence C. Stewart Department of Psychology, University of Waterloo Received 18 September 2009; received in revised form 25 March 2010; accepted 27 June 2010 Abstract Many kinds of creativity result from combination of mental representations. This paper provides a computational account of how creative thinking can arise from combining neural patterns into ones that are potentially novel and useful. We defend the hypothesis that such combinations arise from mechanisms that bind together neural activity by a process of convolution, a mathematical operation that interweaves structures. We describe computer simulations that show the feasibility of using convolution to produce emergent patterns of neural activity that can support cognitive and emotional processes underlying human creativity. Keywords: Binding; Conceptual combination; Convolution; Creativity; Emotion; Neural engineering framework; Neural networks; Neurocomputation; Representation 1. Creative cognition Creativity is evident in many human activities that generate new and useful ideas, including scientific discovery, technological invention, social innovation, and artistic imagination. Understanding is still lacking of the cognitive mechanisms that enable people to be creative, especially about the neural mechanisms that support creativity in the brain. How do people’s brains come up with new ideas, theories, technologies, organizations, and esthetic accomplishments? What neural processes underlie the wonderful AHA! experiences that creative people sometimes enjoy? We propose that human creativity requires the combination of previously unconnected mental representations constituted by patterns of neural activity. Then creative thinking is a matter of combining neural patterns into ones that are both novel and useful. We advocate Correspondence should be sent to Paul Thagard, Department of Psychology, University of Waterloo, Ontario N2L 3G1 Canada. E-mail:
[email protected] 2 P. Thagard, T. C. Stewart ⁄ Cognitive Science 35 (2011) the hypothesis that such combinations arise from mechanisms that bind together neural patterns by a process of convolution rather than synchronization, which is the currently favored way of understanding binding in neural networks. We describe computer simulations that show the feasibility of using convolution to produce emergent patterns of neural activity of the sort that can support human creativity. One of the advantages of thinking of creativity in terms of neural representations is that they are not limited to the sort of verbal and mathematical representations that have been used in most computational, psychological, and philosophical models of scientific discovery. In addition to words and other linguistic structures, the creative mind can employ a full range of sensory modalities derived from sight, hearing, touch, smell, taste, and motor control. Creative thought also has vital emotional components, including the reaction of pleasure that accompanies novel combinations in the treasured AHA! experience. The generation of new representations involves binding together previously unconnected representations in ways that also generate new emotional bindings. Before getting into neurocomputational details, we illustrate the claim that creative thinking consists of novel combination of representations with examples from science, technology, social innovation, and art. We then show how multimodal representations can be com