How much of your body can you consciously control?
Wiggle your toes. Breathe in and out. Lift your arm above your head and wave. These are all comfortable motions for us, minute muscular manipulations that we perform, unthinkingly, everyday. Evolution has gifted us with an astonishing degree of control over these fleshy vessels our brains call home. No nerve is just an ending — our skeleto-muscular system is an intricate and intricately-connected network of muscles, tendons and ligaments all interwoven and hooked up to our spinal chord and hypothalamus.
These parts of our nervous system are in charge of coordination, and translate multiple tiny movements into what seems like a relatively simple action, like grabbing a drink or scratching your nose. Next time you whack yourself in the face or trip over your own feet, you know what to blame!
But how much conscious control do we really possess?
Of course we’re limited on the one hand by the physical restrictions of our joints. We can no more bend our knees backwards than an owl can rotate its head a full 360° (the most they can achieve without cutting off the blood to their brain is 270°). You can swivel the ball-and-socket joint of your shoulder every which way but you can’t raise your arm without executing an awkward shrug like some B-grade 1960’s Frankenstein’s monster. There are also motions that are inextricably linked — you can wiggle your big toe well enough and perform a stumpy little sidestep with your pinky toe, but the best trick the ones in between have is a funny little three-toe waggling salute.
Then again, it’s not fair to bemoan our physical limitations without acknowledging those joints which enable humans to achieve such staggering feats as texting while walking. And so I propose a toast to everyone’s most favorite of joints, the opposable thumb! Oh mighty thumb, it was you who gripped the ropes that built the Pyramids, you who plucked the sweet soft strings of Schumann’s soulful second, you who clutched the One Ring and cast it into the fires of Mt. Doom!
Among the entire animal kingdom it is little coincidence that a species as naturally helpless and vulnerable as Homo sapiens sapiens should inherit the earth. Sure, a charging rhino’s scary and its tough, grey hide is thick, but we’ve got jetpacks (even if they fall short of our sci-fi dreams)! I’d like to see Mr. Tough Guy Rhino work one of those (no, I really would — submit your .gif or fan art below).
As I write this, I’m sitting by a pool in Phan Thiet in Vietnam. I mention this not as a boast but to point out that there’s nowhere you’re more acutely aware of the control you have over your muscles than when you’re in the water. The pressure of the water you’ve displaced as it desperately tries to return from whence it came slows everything down and exaggerates every motion — you have to actively strain each muscle against the weight, and as a result you become very conscious of which bits belong to you and which to your body. I expect floating in the vacuum of space would have a similar effect, although in that case it would come about as a result of your muscles compensating for the lack of ordinary atmospheric pressure — anti-pressure, if you will.
Some functions in your body are off-limits and not able to be directly controlled, in much the same way that the average computer user can’t directly access their system processor core. Now, it’s neither necessary nor even useful to have this functionality — you wouldn’t want to constantly have to tell your processor how much attention to devote a particular task, because it would be both tedious and counter-productive.
I sometimes imagine an awful world where I’m given full control over my own heart muscles. Not only would I have to deliberately clench my chambers in an endless, monotonous cycle, I would probably screw it up and make the blood circulate uselessly, with predictably disastrous results. Still, it’s not some totally foreign function, operating wholly without my input — I can indirectly affect my heart rate by, say, dashing through traffic or facing down Mr. Tough Guy Jetpack Rhino from before. In the processor core analogy, I can do the same thing by double-clicking on a program shortcut twenty-three times in succession in the (extremely futile) hope that it will launch faster.
And so we come to the functions that are semi-autonomous, straddling the line between. The easiest example of this is breathing, but there are many others — blinking comes to mind — functions that are mostly automatic but which we can seize control of if necessary. These always make me feel weird, because they’re a bit like the famous phenomenon where you tell someone not to think about an elephant, and then naturally the first thing that comes into their mind is an elephant, and they can’t get rid of it. Once you become aware of your breathing, it’s very hard to push the conscious rise and fall of your chest aside (distraction from conscious existence is incidentally why online video streaming was invented).
The ultimate in semi-autonomous corporeal entities, though, has to be your brain, or more specifically your thoughts. We like to think that we’re rational creatures, that we’re in full control of our thoughts apart from the occasional rush of emotion or stray intrusion from our subconscious, but this is shockingly far from the truth. Consider songs that get stuck in your head, ones that you find yourself humming incessantly for entire weeks, or that surface suddenly three months after you heard them. Ideas like these are memes, a term shortened from the Ancient Greek mimema, meaning “imitated thing”.
Memes are very interesting because they seem to follow the same kind of selection pressures that are present in biological evolution — if they’re catchy and possess some form of staying power, memes are successful. They don’t have to “do” anything, because just like in biology their only raison d’etre is to replicate. The strange and mildly terrifying part is that we really have no conscious control over the presence of a meme in our mind. We don’t choose what sticks and what doesn’t, not really, which explains why the chorus to Nicki Minaj’s “Starships” has been playing on repeat in my brain for about four years now. The best we can do is occasionally suppress a thought for a brief period of time, or shove it violently into our subconscious only for it to re-emerge later unprompted, like Rosencrantz and Guildenstern in Hamlet.
Our control over our body is, in a lot of ways, rather tenuous. Go take a swim and really think about what parts of your body you’re directly moving, and which are doing their own thing under the guise of following orders. It can be pretty unsettling, but I suppose as long as I have these nifty opposable thumbs it’s hard to complain too much.
Image credit Kurrutra on DeviantArt