Neuroprosthetics

This post is the result of a hypothetical asked by Miss Kim, who runs one of my favorite places to watch girls swing around a pole. She asked: “Would you rather lose your hands or your eyes?” I sort of lack the ability to just answer a hypothetical question like a normal human being; I must seek solutions. Naturally, my response to that was it depends on which one technology is more likely to be able to remedy sooner (and if both are possible, I’ll take both. It’ll further my plan to eventually become a badass cyborg.)

     Based on all the extensive research I was able to accomplish (over the course of a longish lunch). I’ve got to go with eyes. They’ve had reasonable retinal implant prototypes since the early 2000s. They aren’t quite the high resolution images granted by “traditional retinas,” but they’re working on it. The prosthesis is essentially a camera that transmits wirelessly to an implant that stimulates (through microelectrode arrays) optic nerves. The major limiting factor right now is the number of microelectrode arrays (the more you’ve got, the higher the resolution). Also, because this is transmitted wirelessly, you also have to worry about efficient this transfer is (better than the Wi-Fi in my hotel hopefully). Then you have the standard issues with any electrical implant: heat dissipation (no one likes cooked brain matter, except for classy, civilized zombies) and battery life (no one wants to risk brain damage every few months to get their batteries changed).

     Despite these problems, I’m optimistic. The number of microelectrode arrays has been greatly improved upon in the last decade, and wireless technology is rapidly improving. According to a commercial at the theater last night, the new Samsung phones can transfer data amongst one another almost instantly by being held in close contact. I stream video wirelessly on my iPad constantly. Heat dissipation and battery life in all electronics are constantly being improved. There is even research into creating a biochemical battery that’s charged (somehow, I didn’t research it at all) by our bodies. Another option is charging them through wireless energy transfer. It gets exponentially inefficient at range, but if it’s only got to go through a few inches of skull and brain it’s a viable option.

Then again, I have an instantaneous solution for three of the four problems: It doesn’t have to be an implant. Glasses are not an implant, and we get by with them just fine. Hell, in Star Trek the Next Generation which is supposed to be in the 24^th Century, Geordi La Forge had to use his visor, rather than an internal visual prosthetic. This simple design from the 24^th century (ok, actually the late 80’s) makes battery changing/charging a simple task, allows for wired connections to internal implants, and can be air-cooled. Plus, with all that space, I bet you could stick a lot of extra stuff in it. You could have options to see electromagnetic fields and light in the IR and UV spectrums. Magnification and night vision would be a breeze. Plus, if I’m going to be a badass cyborg, I’d want to make sure the humans know it. I want portions of my head incased in metal and scary glowing red eyes like the Terminator (oh, and an HDMI input so I can play video games/watch amusing YouTube videos in my head).

Hand implants are a little farther off. The major factor with hand (or any other limb) implants is that there has to be data transfer in both directions for true functionality. Making prosthesis that respond to nerve impulses is possible, but providing artificial muscle feedback to let you know how hard you’re pushing/pulling/squeezing etc. is the problem. Imagine trying to pick up an egg without being able to feel how much pressure you’re putting on it? Or what if you’re interrogating a space pirate and you only want to choke them enough to get information without killing them? I shudder to consider the risks associated with using such a prosthetic hand for certain discreet adult activities (ouch!!).

So really, you need the sensory feedback. There is some promise in attempts to do this, but it’s tricky and solutions are probably a decade or two off. However, I think other forms of feedback could be used in the meantime. We frequently perform manual tasks with only non-physical feedback, and we rapidly learn to respond in a near instantaneous fashion. Think about video games (I usually am). Responding only to visual and audio feedback (and the occasional vibration on newer systems) we manage to perform some pretty complex motions with our fingers and thumbs. Also consider how rapidly our brain remaps those motions. We aren’t thinking “lift thumb, move forward and to the right, now press down,” we’re thinking “B,” or even “Melee attack” (or more likely “beat down that damn dirty alien.”) The even more amazing thing is how quickly our brains can remap these controls. Sure, immediately after switching from Mass Effect, to Modern Warfare I may have accidentally thrown a flash bang when I wanted to change weapons, but within fifteen to thirty minutes, I had no problems. For all you weird, non-gamer people, a reasonable example might be driving a car. When you want to turn right, you don’t think “pull downward with right arm while simultaneously pushing up with left arm, release right arm, continue pulling to the right and eventually down with left arm” you just think “go right.” With experience, our brain essentially bundles actions into a single process. In both cases we’re operating primarily on feedback from our other senses, rather than responses from our muscles.

Because of the brain’s ability to control muscle (and thus prosthesis) movement based on other forms of sensory input, it seems like we could come up with other forms of feedback to effectively operate prosthetics. Maybe a light or vibration that lets you know how much pressure you’re applying could work. In the case of badass cyborgs, it’d be easy to superimpose various meters in the lower corners of the visual input. I’d find the sweet-spot for safely picking up an egg or non-lethally strangling a space pirate just as quickly as I mastered jump shots on NBA Live. Speaking of video games, I could probably even make it so that I can hook straight up to the Xbox, without even using the controllers. Plus, there have to be options for attachments. I’m thinking Gatling-gun arm like Barrett in Final Fantasy 7, or at very least a combination cork-screw/bottle opener.

So I guess, to answer the original question: BOTH (but not for ten to twenty years, when the technology catches up). I wonder when they’ll be able to do robot legs . . .