COMPUTATIONAL MODELLING OF EMOTION AND REASONING Suzanne C. Lewis and Darryl N. Davis NEAT Group Department of Computer Science University of Hull, Cottingham Road Hull, UK S.C.Lewis@dcs.hull.ac.uk Abstract CRIBB (Children’s Reasoning about Intentions, Beliefs and Behaviour) is a computational model of belief-desire reasoning. This paper presents an analysis of CRIBB and the initial design for an extension that involves the implementation of a model of emotions. The impetus for this research is evidence that emotion plays a fundamental role in a variety of cognitive functions such as decision-making, learning and perception. We consider theories of emotion, perception and reasoning and also the affect that emotion has on these cognitive processes. We discuss how these theories can be modelled and integrated into the CRIBB model and present a proposed initial design for an emotional model. Keywords Emotion, Computational Models, Perception, Reasoning. Introduction The question of what an emotion is has been addressed by psychologists, philosophers and neuroscientists over many years. However, no consensus has yet been reached. The lack of an objective measure to conclusively establish whether a person is experiencing an emotion has led to many contrasting theories and views of emotion being formed. The traditional perspective of emotion is of something that is irrational and detracts us from reasoning. But, scientists have recently learned of many surprising roles played by human emotions especially in cognitive processes such as perception, decision-making and memory. This evidence leads us to believe that emotions are an essential part of human intelligence, including rational decision-making and learning. Therefore, emotions are believed to be a vital part of any system that attempts to imitate human intelligence computationally. The aim of this research is to investigate theories of emotion and how they can used to form a better computational model of reasoning. This paper describes the analysis and initial design for the integration of an emotional model into an architecture for belief-desire reasoning. Theories of emotion, perception and reasoning will be discussed along with how emotion affects both these cognitive processes. This leads a description a belief-desire model and the design of how emotion can be incorporated into it. Psychology and Emotions Emotions and their nature have been studied for a large number of years and throughout this time psychologists have proposed a wide-range of diverse theories of emotion. Darwin’s [6] theory has an evolutionary basis in which he claims that emotions are a by-product of evolutionary history. Emotions are either simply dependent on how the nervous system is ‘wired-up’ or possibly are remnants of old habits. He also maintains that facial expressions of emotions are merely something that occurs in conjunction with emotion and serve no communicative function. The James-Lange theory, based on a physiological approach, is one of the best known theories of emotion and presents an entirely different view to emotion. James proposed that bodily changes directly follow perception and these bodily changes then lead to the feeling of emotion [21]. His theory of bodily patterns affecting emotions lead to research and theories which stress the importance of facial and bodily expressions in emotion. Ekman is one of the investigators researching into this area. He derived six basic emotions from research performed into universal facial expressions: fear, anger, disgust, happiness, sadness and surprise [9]. Ekman believes that there are three differentiated but interrelated systems involved in the elicitation of emotion: cognition, facial expression and ANS (autonomic nervous system) activity, with an emphasis on facial expression. The appraisal approach has cognition as the core element in emotion. The OCC (Ortony, Clore and Collins) model [18] synthesises emotions as outcomes to situations. Emotions occur from a valanced reaction to situations consisting of events, objects and agents. The emotion type elicited is dependent upon appraisals made at each branch of the model. It also allows for an emotional state to be a situation itself, so emotions can trigger additional emotions or the same one repeatedly.