There she sat, quietly watching TV with her 77 years, when suddenly in her eye corner something appeared.It was a hand, her hand, who started stroking her cheek and her. This was not her will, the hand did this from herself! 30 disturbing minutes passed after which her left hand again did what she wanted.
Our brain, our beautiful complex brain.
There is a lot going on in our head, information being processed, we see the world, make choices, move our bodies. The brain is where the most part of “You” is, which makes you the person you are. So…. Let us throw that brain over.
The concept of “consciousness” is a tricky one, especially with subjects where biology and psychology mix with a subjective experience.We feel like ourselves, though that is a bit of an illusion, a little one that our brain tells us.
You are no more the same person than 10 years ago, in 10 years you are no longer the same person than now, yourself reading this text changed who you are.Yet you always feel like yourself, your whole life long.
At this time, the subjective experience, “you”, can move your left hand and right hand.You control your body, move your hands because you want it. In Real “Wanting” is a little more complex and there is a chance that this whole movement will be determined before “you” know it, but that is another story.
That left hand is controlled by your right hemisphere, while you get right-hand commandos from your left hemisphere.These two halves chat with each other and tune everything together. Links know what’s right and visa versa.
So that goes with a lot of things.
Your eyes cross, movement, feeling, emotions, language. A lot of functions travel through the brain, from front to back, from left to right. It is a complex organ. Much of the communication between left and right goes through the Corpus Callosum, a thick bundle of nerves in the middle, a kind of highway.
Let’s cut that highway once… What now?Sounds scary, it is also, worse still it is not a hypothetical situation. These types of interventions have been used in the past to help people with severe epilepsy. It was quite successful, but luckily we have better methods nowadays.
Our epilepsy patient has traditionally suffered less from seizures, but the left and right hemisphere can no longer communicate as well as first.The patient is what is known as a Split-Brain patient, and we have been able to learn a lot from these patients.
The most disturbing thing that can happen to these patients is called Alien Hand Syndrome, and it’s pretty spooky (not always happened anyway).In this syndrome, patients lose control of their left hand (the hand controlled by the right hemisphere).
Stories you hear is that they are close to their shirt, that their right hand makes the buttons close and the left hand opens the buttons.Sometimes the behavior is a bit shameful, that the left hand suddenly groped someone inappropriate or even a blow out. It can also be a little scarier, that the hand throws a drawer with the other hand in it, or even a left hand that grabs to its own throat.
Often, however, it is less scary, but disturbing.
The example I mentioned in the beginning, of a 77-year-old woman (no split-brain incidentally but another condition) was watching nice TV. This lasted about half an hour, after which she got the control back but had less feeling in her arm.
In All these cases, the communication between the two cerebral hemispheres is broken.Links do not remember what right does and right do not know what left wants. That is why the lady in the story only noticed something when her hand came into her visual field. The fact that her hand was moving was processed by her right hemisphere, but could not be passed on to the left, only when she saw it and that visual information came in the left half, she became aware of it.
Behavior is no longer aligned, allowing legal things to do without modifying or stopping links.Now it is that our language is left, our subjective experience therefore seems to be left too because there is the talking half.
Another strange side effect has to do with how you see it.You may have heard that your left eye is going right and your right eye to the left. That’s not entirely true, it’s your visual fields that cross. The left side of both eyes goes to the right and vice versa.
With split brain the information no longer arrives in both cerebral hemispheres.Normally you notice little of this, we see with a lot of overlap, we move, so eventually both sides see enough. In The lab we have some more control and we can show something to just the right side.
Let’s see a pen on the right, the screen goes out and questions what they saw.The patient has no idea, on the right the picture of the pen cannot be forwarded to the left where the word is. Then we ask the patient to feel some objects with the left hand (without seeing this). The word never came out, but the left hand can pick that pen out flawlessly, even objects that only have something to do with a pen. Right had seen it for sure, knew what it was, could pinpoint it. Left had no idea because it did not have all that information.
After a while the brain find a new way, left and right can communicate again, and strange symptoms like Alien Hand Syndrome disappear.
It does give us an interesting look into the functioning of the brain, it is not all as simple as that it feels.
A split brain works independently.Are these also two separate persons? I don’t think so, it’s both you, just another part of you. “You” are then split up and communication is only possible with the talking half, half with the brain function to communicate. The other half of “You” is also there, which now works independently with the information it has.
Your brain is great information processing machines (Scrabble Word!), you use the whole body to process data every day, all day, and to reach conclusions.If we divide the thing, we also split the processing process. Often, left and right come to the same conclusion, but sometimes (as with Alien Hand Syndrome) There are two different conclusions.
With the same input from the outside, links says “Close buttons” while right thinks “buttons open”, internally they may have access to other additional information, which will send the choice a different side.How that is in each other, no idea, so far we are not yet. Philosophically, you can also think about whether “you” exists, but I’m not going to do that, I only do nice brain thingies.
Would you stop the two halves in another body (provided you can clone the brain parts that cannot be split or something like that), then you have a slightly different situation.
I imagine that as if you spontaneously get twins, “You” are now two people (both with a different handicap) and as time passes those two people will gain other experiences and become something other people (also, how did you ask the split Makes).