When Does Virtual Embodiment Change Our Minds: Stanford VHIL Study
(This study by Bailey, J.O., Bailenson, J.N., & Casasanto, D., was originally published on Stanford University's Virtual Human Interaction Lab website in Oct. 2016. Read full study here. )
Can an avatar’s body movements change a person’s perception of good and bad? We discuss virtual embodiment according to theories of embodied cognition (EC), and afferent and sensorimotor correspondences. We present an example study using virtual reality (VR) to test EC theory, testing the effect of altered virtual embodiment on perception. Participants either controlled an avatar whose arm movements were similar to their own or reflected the mirror opposite of their arm movements. We measured their associations of “good” and “bad” with the left and right (i.e. space-valence associations). This study demonstrated how VR could be used to examine the possible ways that systems of the body (i.e. visual, motor) may interact to influence cognition. The implications of this research suggest that visual feedback alone is not enough to alter space-valence associations. Multiple sensory experiences of media (i.e. sensorimotor feedback) may be necessary to influence cognition, not simply visual feedback.
From being swept away by characters in a book, or feeling heart palpitations while playing a first-person shooter videogame, users’ minds and bodies connect with mediated environments. Media-technology provides users with dynamic interactive experiences. An embodied cognition (EC) framework may explain why humans get absorbed in mediated experiences in sensory (e.g., visual feedback on a screen) and non-sensory environments (e.g., text in a physical book). According to an EC approach, cognition is grounded in the body and in the body’s relationship to the environment. Mental representations are stored through a multimodal system (various systems of the body) that integrates memory, perception (e.g. vision), action (e.g. movement), and introspection (e.g. emotion; Barsalou, 2008; Barsalou, 2010). Humans spend substantial portions of their day navigating highly interactive media environments. The capabilities of new media-technology allow for greater mapping of interfaces to human body movements. For example, using a home video game console system is no longer a static experience involving abstract motions (i.e., a button press) that simulate movement in a virtual environment. Instead, game play can reflect the user’s body movements in real-time with controls that capture the player’s body movements. Phone and tablet interfaces have become more user-friendly by employing direct motions for control, such as a simple flick of the wrist, or a swipe of a few fingertips. Integrating interface control into the body not only provides ease, but also could have psychologically effects on the user’s experience. Research studies show that more natural mapping in video games can increase users’ psychological presence in and enjoyment of the virtual game (Kim & Sundar, 2013; McGloin & Farrar, 2011; Schmierbach, Limperos, & Woolley, 2012; Skalski, Tamborini, Shelton, Buncher, & Lindmark, 2011; Tamborini & Bowman, 2010). Leveraging virtual embodiment, immersive virtual reality technologies provide unique opportunities to empirically explore EC theory (Banakou, Groten, & Slater, 2013; Maister, Slater, Sanchez-Vies, & Tsakiris, 2015; Romano, Llobera, & Blanke, 2016; Schubert, Friedmann, & Regenbrecht, 1999). Users map their body schema onto the affordances of their virtual bodies and consider them to be extensions of the self, creating an embodiment illusion (Biocca, 1997; IJsselsteijn, de Kort, & Haans, 2006; Lenggenhager, et al., 2007; Petkova, & Ehrsson, 2008; Slater, et al., 2009; Slater, Spanlang, Sanchez-Vives, & Blanke, 2010). Through immersive virtual reality, users can interact with an environment in ways that are unusual or impossible in the physical world. Imagine, as a human, controlling an avatar with a tail (Steptoe, Steed & Slater, 2013) or having the capability of three arms to complete a task (Won, Bailenson, Lee, & Lanier, 2015), and then imagine how these experiences could impact your perception view of the outside world. Given the development of interfaces with natural physical mapping, and the connections people form with their digital representations, how can the movements of an avatar alter how people think, feel, and act in their own bodies outside of the virtual environment? This paper describes how mental representations of mediated interactions may be rooted in the body, and presents some of the psychophysiological effects of virtual embodiment on users’ behaviors and attitudes. An example of experimental research with immersive virtual reality is presented to illustrate how to utilize VR to test EC theory. The study examines the influence of virtual embodiment on perception, specifically associations of “good” and “bad” with the left and right. Finally, we discuss what the study results could mean for virtual embodiment and interface design.
Read full study here.