Extended Reality Technologies: Expanding Therapeutic Approaches for PTSD.

FIGURE 1. (A) Extended-reality (XR) platform elements. XR (i.e., virtual reality [VR], augmented reality [AR], and mixed reality [MR]) is an emerging imaging paradigm characterized by varying levels of a user’s immersion, interaction, and presence. Immersion refers to the sensation of physical existence within the extended reality environment, where a user is isolated from the real world. Interaction is described as the capacity to act and receive feedback within the digital environment. Presence appeals to the perception of connection to the artificial environment, evoking the illusion of being present within it (1, 2). (B) XR technology platform. In VR, the user experiences a full immersion into a nonnatural digital world, facilitated by a head-mounted display (HMD) that provides sensory input (i.e., images, sound) (3). In AR, the user is partially immersed into an artificial environment but can interact with the real world, as well as with virtual elements in the digital world concurrently. Different from VR, an AR user can always experience his or her own reality in real-time (4). MR poses as a subclass of VR, combining real and virtual milieus along a “virtuality continuum,” seamlessly integrating real-world and artificial digital scenes with a superior level of connectivity and higher computer-user interactions (3, 5).