Thursday, September 14, 2006

We Can Rebuild Her

It's been raining here today, off and on, so any hope we had of making progress in ridding our back yard of the last of the excavation dirt pile was in vain. The pile o' dirt remains. Instead we've been hanging cabinets in the Disneyland-in-the-making-for-people-who-like-power-tools that is our new garage. They are cabinets, I might add, that we got for free when somebody started a kitchen remodel project. The "for free" part is especially gratifying. This building project was by no means cheap. The cabinets weren't cheap either, but somebody bore the cost for them that wasn't us. A happy thing in Meowville.

So anyway, my husband is off rescuing my stranded mother (car trouble), and I turned to my favorite down-time activity. If you don't know what that is, this is clearly your first time visiting my particular bit of Internet real estate. I'm catching up on a little reading. Almost any kind of reading material would do, except for communist propaganda, or the kind of magazines that used to come with brown wrappers over them, but today what caught my eye is a bit of tech talk.

Having recently had both my arms very actively engaged in holding cabinets overhead while my Kedley attached them to the wall, it struck me personally when I came across an article which talked about the first woman to receive a bionic arm. I couldn't help thinking about all the ways in life that we (most of us anyway) depend on the fact we have two working appendages, with all the appropriate moving parts. The Washington Post article, by David Brown, tells the story of Claudia Mitchell, who lost her left arm at the shoulder, in a motorcycle accident, and says that the first time she "peeled a banana one-handed, she cried." Obviously, the situation really is personal to her, and not just a mental "wow, arms are really important" moment. Her whole life was transformed with that accident, and how could that ever be made better?

What's amazing is that, while she's not growing a new arm, or anything, to replace the one she lost (science hasn't progressed that far, although when they do get there, I'm sure it will involve carbon nano-tubes), she has been given a reasonably-functioning replacement to the limb she came with at birth. When I said earlier that her new arm was bionic, I meant it. This isn't just a prosthetic part with no real function. Doctors actually moved nerve clusters to different muscles than they were originally connected to, making this new arm respond to Mitchell's thoughts.

Apparently, even when an arm is lost at the shoulder, higher up toward the brain the nerves still exist which transmit messages from the brain to our limbs. Those nerves can be adapted to trigger impulses to other muscles than the ones they originally controlled, so Mitchells' "hand and arm" nerves were attached to chest muscle, which twitches when she thinks about moving her hand, or elbow, or whatnot. That muscular motion is sensed by electrodes that let a computer in the bionic arm know which motors to activate to move in response to Mitchell's thoughts. By this method, she can grab things with her "hand" and move the arm at will. Right now, there are three motors in her arm. They're working on one that will have six, and allow her to reach overhead for things that she can't get to currently, which could be very useful if she ever needs to put up overhead cabinets. Wouldn't that be absolutely amazing?

According to Brown, the part of the chest muscle that has been wired to the hand nerve cluster actually feels as if it were her hand:

The person also ends up with a patch of skin about the width of a baseball that, when stroked, warmed or pricked, feels like a hand rather than part of the chest.
What's really cool about this is that eventually the signals will go both ways. Not only will Mitchell's mind send signals to the hand, but the hand will send signals to the brain as well. Sensors in the hand will transmit to the brain, through those nerve impulses that are now routed through the chest muscle, allowing her arm to send messages that "...will be perceived as sensation." Astounding, isn't it? The Bionic Woman is a reality. Brown says Mitchell is the first woman, and only the fourth person ever, to receive this kind of arm--the thought-controlled variety.

There are lots of things still being worked out, but the implications are mind-blowing. As this technology improves, accident victims and soldiers will be increasingly able to face future life with hope that whatever injured them won't be a permanently life-altering event. Who knows where this will lead? Scientists are constantly pushing the boundaries, and finding new wells of genius from which to draw. I find myself wondering if the day will come when bionic limbs will have such functionality and appearance that no one else even knows that the person playing tennis with them lost an arm, or a leg. Amazing, astounding, and mind-blowing. I'm running out of superlatives.

Hat tip: Futurismic