Examining the Use of Nonverbal Communication in Virtual Agents

Virtual agents are systems that add a social dimension to computing, often featuring not only natural language input but also an embodiment or avatar. This allows them to take on a more social role and leverage the use of nonverbal communication (NVC). In humans, NVC is used for many purposes, including communicating intent, directing attention, and conveying emotion. As a result, researchers have developed agents that emulate these behaviors. However, challenges pervade the design and development of NVC in agents. Some articles reveal inconsistencies in the benefits of agent NVC; others show signs of difficulties in the process of analyzing and implementing behaviors. Thus, it is unclear what the specific outcomes and effects of incorporating NVC in agents and what outstanding challenges underlie development. This survey seeks to review the uses, outcomes, and development of NVC in virtual agents to identify challenges and themes to improve and motivate the design of future virtual agents.