Friday, 30 September 2016

If you can’t find you limbs

We all know our five senses. But, we have many more senses than just those five. We have the sense of proprioception, for example, that helps you keep track of where your body parts are. But, what if you lack that?

Where’s my nose?
Proprioception is, the sense that allows you to touch your nose with your eyes closed, or type without looking at your hands. The reason for this is that your brain knows where your hands and nose are without necessarily having to look at them. And that’s what proprioception does. But what if you don’t have that sense? What if you’re blind, but instead of lacking sight, your proprioception did not work.

Hard to find that sense
Well, it’s quite hard to study that. Because the symptoms of lacking proprioception aren’t as clear as, say, lacking hearing. Another things is that the sense isn’t located at one point in your body, unlike, for example, your eyes. Eyes have a specific place and you know exactly what they do; they see. But with proprioception, the location isn’t really clear. The sense is working all over your body. So you know where all your body parts are hanging out. But this makes it really hard to study this sense.

9 and 19
Fortunately, Carsten Bönnemann and his team have found two people; a nine-year-old girl and a nineteen-year-old woman who totally lack proprioception. With their eyes closed, they can’t tell where they limbs are, or in which way their joints are being moved. With their eyes open, they can tell, but they can only do so if they actually see what’s happening. The researchers considered the situation of the woman and the girl to be so weird that they did a genetic test on both of them. The scientists discovered that both of them have an extreme mutation in a gene called PIEZO2. Scientists already linked this gene to our sense of touch earlier, which made Carsten Bönnemann and his team think that PIEZO2 plays an important role in proprioception.

Whoops, I didn’t mean to…
The discovery of this gene also has another advantage, especially when you’re a bit clumsy. Clumsiness has already been linked to your sense of proprioception not working perfectly. Since proprioception is linked to the PIEZO2 gene, this means that, if you’re clumsy, you may have a mutation in that gene. It doesn’t have to be extreme to the point that you totally lack the sense. But if it malfunctions a bit, this could also be reason enough for you to tip over glasses of water a little more often. So don’t worry, it’s not your fault, it’s just your genetics.

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