Chapter 37. Sensations, Emotions, and Feelings

Key Topics

• Sensations

• Emotions

• Interfaces for Communicating Emotions

• Portraying Emotions in Games

Emotions arise from complex interactions between the body and the brain. Emotions begin in the body, influenced by stimuli from the environment (such as an explosion). The brain generally responds to these low-level perceptions, which translate into persistent characteristics of the creature (as fear). These emotions can potentially become visible externally via behaviors (running away).

This chapter defines the different concepts involved when creating artificial emotions in animats. The lower-level concepts are presented first as we move toward higher-level emotions.

This chapter covers the following topics:

• A definition of sensations as the brain's reaction to perceptions, which drive emotions

• A description of emotions as a persistent characteristic, with the concepts of moods and feelings derived from emotions

• An interface used by the AI to communicate emotions to the game engine

• (New) ways to portray the emotions in practice within the game world

At the end of this chapter, an understanding of the different aspects of emotions permits the implementation of an emotional system. Extending the animats is possible thanks to new interfaces dedicated to emotions.