Grafting 101

In a previous post I wrote about how an immersive virtual reality (IVR) system would have to work and how many portrayals in popular television and movies get it wrong. I established that such a system would necessarily be invasive, having to connect itself to every neuron in the peripheral nervous system. Warning: What follows is a rather technical discussion rife with medical and engineering terms.

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The crude cables shown in The Matrix, though definitely invasive, do not begin to capture it. To reiterate, every retina cell, every cochlear hair cell, every olfactory sensory neuron, every proprioceptive (joint position) neuron, and every other neuron in peripheral nervous system would have to be freely modulated by such a system. Every channel of sensation would have to be controlled. Anatomically, each of these channels is kept separate until it is highly processed by the brain (separately), and only after each are processed (separately) do specialized areas of the brain integrate them. As a consequence of the channels being processed in parallel, there is no one convergent area that could be targeted or manipulated for the purposes of an IVR system. Thus it has to be the complete peripheral nervous system, i.e. all the neurons comprising the 24 cranial nerves and 62 spinal nerves.

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How might this be accomplished? My own idea, while still fanciful and well beyond current technologies, does have a certain conceptual soundness to it. That is, it would work in theory. I call it a peripheral nervous system graft. Rather than a surgically-installed device, the PNS graft would sprout and grow into the body as a synthetic organism. I imagine an genetically-engineered virus that would ‘infect’ peripheral neurons selectively and transform them into syneurons. The syneurons would function identically to and maintain the same connectivity as the cell from which they were born, but would bud and form new connections with a central hub. As the central processor of the device, the hub would implement the control loop that I described previously. I picture it residing somewhere in the abdomen.

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Thus, sensory input from the real world would be blocked and simulated reality from the hub would be fed in instead. Likewise, motor output from the brain would be captured and applied to the simulated environment (to a virtual body) and the proxy software would generate whatever motor output it was programmed to do for the real body.

Imagine hanging out with your friends in a virtual club while your proxy does a work-out routine with your body in the real world. You could have virtual feasts on simulated food and return to the real world with an empty stomach. Sound good? Here is where one’s imagination can take off.

There is much more to say about devices such as these, but what is particularly interesting to me are the ethical, moral, and societal implications. My novel delves into just a few of them. It is true that, while theoretically sound, the above is just speculation on my part today, but as we see increased use of mobile computing (smart phones and tablets) and augmented-reality devices (Google Glass), we will begin to grapple with many of these issues.