We go beyond gaming to explore how VR works, what it's being used for (from treating a fear of spiders, to training young doctors) and ask if it's yet making any compelling case to be in every home.

From treating a fear of spiders to training young doctors - how real is the promise of Virtual Reality and how is it being used today?

Virtual reality, or VR, tricks our brains to immerse us in any reality we can imagine. It was originally developed by the US military in the 1960s, but today it's gamers who are the early adopters driving demand and innovation.

Meanwhile, the biggest companies in the world are banking on VR hitting the big time - but no one has yet found that 'killer app' to propel this technology into the mainstream. Will it take another blockbuster game like Pokémon Go, or could VR's uptake be driven by the fact that most of the new smartphones in production today are VR-enabled?

What is VR

The easiest way to understand VR is to place a finger in front of your eyes, then quickly open and close your right and left eyes; you should see the finger move. Well, it's this movement, or the difference between these images, that provides the 3D quality to images in VR. So a bit like a 3D film, VR shows each eye a different image, and then your brain does all the work to give images depth and create a 3D effect.

Dr Wendy Powell is a Reader in Virtual Reality at the University of Portsmouth in the UK. She says that VR revolves around replacing our senses with content that is generated by a computer.

"Our most dominant senses are our senses of sight and hearing, so in virtual reality, your vision - and usually your hearing - is completely surrounded by computer-generated content, sometimes even your sense of touch as well. Everything you see and hear isn't real, but because it is dominating your vision and your hearing you believe that it is real, and you engage with it is like it is real because you want to believe that it is."

Professor Rob Lindeman leads the Human Interface Technology Lab at the University of Canterbury. "Virtual Reality is really this tight coupling between actions by the user and reaction of the system", he says. "So as I turn my head the screens will update what I see ... If the brain receives signals it is expecting, then typically you have an effective virtual experience."

Our brains are designed to fill in patterns and missing information, so if you can feed the senses with enough of an experience from a visual and auditory point of view, then our brains will try to complete the picture by filling in what we expect to see…

Go to this episode on rnz.co.nz for more details