Do you remember the film ‘Inception’ with Leonardo Di Caprio starred? In this film he plays the role of an industrial spy who is hired to plant an idea in the mind of a businessman by one of his rivals. There Di Caprio's hero can make one dream within one's dreams in such a way that he/she is unable to distinguish between the reality and the dream fabricated specially for that person.
The conceit of creation of the helmet is similar to the plot of this thriller — it simply makes you feel unable to distinguish between what is real and what isn't.
Let’s see how this wonder works: The equipment mainly includes the glasses with the camera embedded and the headphones. A test person sees the record from the outer camera and the layer record at the same time. The latter was made in the same very room using special equipment. The sound and the image are tuned for the person not to distinguish the border between the real things that take place in the room and the 'artificial reality' record. As reported, people really couldn't make a difference!
Without hesitations, the scientists deserve appraisal and so on. But I fear to imagine what can happen if this helmet will be accessible for other people and used for mercenary motives…