Virtual reality: How much immersion is enough?

Immersive VR-complex technologies that replace real-world sensory information with synthetic stimuli such as 3D visual imagery, spatialized sound, and force or tactile feedback-has generated much excitement. The goal of immersive virtual environments is to let users experience a computer-generated world as if it were real, producing a sense of presence, or being there, in the user's mind. To a large degree, VR researchers have succeeded in achieving this goal. Clearly, immersive VR is unique, but practitioners are using a relatively few examples of immersive VR systems in the real world. Even so, the technology has already provided success stories in fields such as military training, phobia therapy, and entertainment.