Microexpressions in Digital Humans: Perceived Affect, Sincerity, and Trustworthiness

Tastemirova A; Schneider J; Kruse LC; Heinzle S; vom Brocke J

Abstract
Digital agents with human-like characteristics have become ubiquitous in our society and are increasingly relevant in commercial applications. While some of them closely resemble humans in appearance (e.g., digital humans), they still lack many subtle social cues that are important for interacting with humans. Among them are the so-called microexpressions--- facial expressions that are short, subtle, and involuntary. We investigate to what extent microexpressions in digital humans influence people's perceptions and decision-making in order to inform the practices of digital human's design. Our two experiments applied four types of microexpressions based on emotion type (happiness and anger) and intensity (normal and extreme). This paper is among the first to design and evaluate microexpressions with different intensity levels in digital humans. In particular, we leverage the possibilities of digitally (re)designing humans and human perception. These possibilities are feasible only in a digital environment, where it is possible to explore various microexpressions beyond real human beings' physical capabilities.

Keywords
Microexpression; Digital human; Conversational agent; Human–computer interaction