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Abstract

Virtual reality exposure therapy (VRET) is already used for treatment of phobias like fear of flying, heights and small places. It is shown to be effective in these areas prompting research into new phobia treatment possibilities. Current papers concerned with social phobia and the use of VRET do not seem to focus on person to person interaction. One of the problems that might have caused this is the difficulty of automating the interaction between a human and a computer character. In this thesis the focus lies on evaluating a possible technique for automating the interaction between a human and a computer for use in a therapeutic setting. The chosen method used avatars which behaviour was simulated using various artificial intelligence techniques. Some of the techniques used in this thesis were borrowed from research related to chatbots and embodied conversational agents. Because these type of conversational agents are not used in a therapeutic setting, the techniques had to be altered to fit this extra requirement. This produced a semi-scripted dialogue structure that would be executed. The user was asked a question and in return the computer would respond on the given answer. A speech recognizer was used, to figure out what the user had said in his free speech response, to choose a predefined response fo