Understanding the Impact of the Reality-Virtuality Continuum on Visual Search using Physiological Measures

While Mixed Reality allows the seamless blending of digital content in their surroundings, it is not clear if such a fusion of digital and physical information impacts users' perceptual and cognitive resources differently. While the fusion of real and virtual objects provides numerous opportunities to present additional information, it also introduces undesirable side effects, such as split attention and increased visual complexity. We conducted a visual search study in three manifestations of mixed reality to understand the effects of the environment on visual search behavior. We conducted a multimodal evaluation using EEG and eye-tracking correlates of search efficiency, distractor suppression, attention allocation, and behavioral measures. We found that, independently of the perceptual load, Augmented Reality environments reduce users' capacity to identify target information and suppress irrelevant stimuli. Participants reported AR as more demanding and distracting. We discuss design implications for MR interfaces based on physiological inputs for adaptive interactions.