Emotion plays several important roles in the cognition of human beings and other life forms, and is therefore a legitimate inspiration for providing situated agents with adaptability and autonomy. However, there is no unified theory of emotion and many discoveries are yet to be made in its applicability to situated agents. One function of emotion commonly identified by psychologists is to signal to other cognitive processes that the current situation requires an adaptation. The main purposes of this chapter are to highlight the usefulness of this signaling function of emotion for situated agents and to present an artificial model of anger and fear based on mismatch theories of emotion, which aims at replicating this function. Collective foraging simulations are used to demonstrate the feasibility of the model and to characterize its influence on a decision-making architecture.
Psychology is a natural inspiration when designing a model of artificial emotions. However, to clarify its possible contributions to a model, it is useful to classify different theories coexisting. Frijda (1986) proposes such a classification based on three main categories: specific-stimulus theories, intensity theories, and match-mismatch theories.
Key Terms in this Chapter
Concerns: Dispositional entities representing states of the world, which should be attained and which are present in the system prior to the encounter of an event. Needs, motives, goals, expectations, and commitments are concerns.
Coordination: Managing dependencies of activities and goals of agents working together towards a mutual objective.
Adaptability: Ability to autonomously modify its decision-making mechanism to make it relevant in an unforeseen situation.
Discrepancy: Difference between what is perceived and what is expected. Expectations coming from biological evolution or learning. Discrepancies imply a response, an arousal in the sympathetic nervous system and are thus part of the emotion process.
Situated Agent: Physical or virtual entity which is situated in a dynamic, quasi-continuous environment, which it perceive through sensors and into which it operates autonomously.
Intention: State of the world which is the purpose of an agent action. Action tendency towards a goal.
Autonomy: For a situated agent: freedom from human guidance during operation. Ability to adapt to variations of its environment without human action.