Virtual environments, also referred to as online social spaces, are artificially constructed and allow users to sense a space and artifacts or others in that space apart from the physical environment they are in. This cumulative dissertation explores human interaction with technological artifacts in virtual environments. Specifically, persuasive technologies, which are interactive systems that can influence human attitude or behavior through inscribed cues by reinforcing or changing a target behavior are in the focus of this dissertation. Whether inscribed cues for action are correctly perceived and used by humans, depends on the real (designed) as well as the correctly perceived technology action potentials. In this dissertation, both aspects of persuasive technologies, their capacity to influence behavior and their requirement to be correctly perceived by users are explored in a series of qualitative studies. Accordingly, this dissertation is structured in two research streams, which focus on 1) the influence of digital nudges on user decision-making (research stream one) and 2) aspects influencing user perception of technology action potentials in socio-technical relationships (research stream two). Therefore, two theories, the digital nudging, and affordance theory are used to provide theoretical backgrounds for the empirical observations and explanations for the different forms of influence on human decision-making and perception in virtual environments. In general, digital nudging can be understood as user-interface design elements that influence humans towards a target behavior, while affordances likewise present the material aspects of a technology that offer action potentials to users. Research stream one presents status quo analyses, theoretical discussions, and an empirical assessment of interactive digital nudge design in dynamic virtual choice environments. The digital nudging research conducted in this dissertation contributes to the conceptual clarity of digital nudging theory, integrates ethical considerations in the design of digital nudges, and explores potentials of digital nudges in dynamic choice environments. While digital nudging research (rooted in behavioral economics) shows a long history of research and empirical observations on cognitive aspects of human-artifact interaction in virtual environments, affordance research (rooted in ecological psychology) is largely missing conclusive explanations of changes and factors influencing perception and consequent behavior. Therefore, existing conceptual boundaries of affordance perception are extended in this dissertation to include cognitive aspects of perception in affordance research. Accordingly, research stream two presents theoretical discussions and empirical assessments of the role of in-built IT artifacts as facilitators of affordance perception and the potential of integrating cognition to extend the understanding of perception and consequent behavior in affordance contexts.
