Mixed reality

Mixed reality (MR) is the spectrum of experiences that blend physical and digital environments, ranging from augmented reality (digital overlays on the physical world) to augmented virtuality (physical objects integrated into virtual spaces). Unlike virtual reality, which replaces the physical environment entirely, mixed reality preserves the user's spatial and bodily relationship to the physical world while adding computational capabilities.

The defining challenge of mixed reality is not technical but perceptual: how to maintain a coherent sensorimotor loop when the user's actions in physical space produce effects that violate physical causality. When a user grasps a virtual object, there is no haptic feedback; when a virtual object occludes a physical one, the depth cues conflict. The brain's predictive processing mechanisms, evolved for a consistent physical world, experience these inconsistencies as cognitive strain.

Mixed reality is the most demanding test case for embodied interaction design: it asks the body to operate simultaneously in two ontologies — the physical and the computational — that obey different rules. The interfaces that succeed will be those that resolve this conflict not by making the virtual more physical, but by making the boundary between them cognitively tractable.