whose side are you on?

In this post, I'd like to do something I rarely do and indulge my dorky fascination with the human body and medicine. Over the past few weeks I've been overindulging in House and dreaming about being a nurse, and through both pastimes I've become reacquainted with various medical subjects that I find fascinating. The one I'd like to talk about today is corpus callosotomy, which is a fancy term for "split-brain surgery".

The human brain is the most sophisticated and advanced thing on the planet, and is very under appreciated. Scientifically, we haven't even begun to understand everything its capable of. Fuck iPhones, your brain is SO much cooler. Its composed of a variety of parts like a big squishy puzzle, and like a puzzle, some of the parts can be removed without compromising the entire picture. 

Before I launch into what exactly corpus callosotomy is, and what is its purpose, there are a few things I should explain about the human brain. First off, your brain is composed of two hemispheres - the left and right. They are joined in the middle by a structure known as the corpus callosum - its kind of like a bridge between the two hemispheres. While some may think of the brain as operating as a whole, the two hemispheres kind of work on an assembly line basis. Each hemisphere processes and sends out different signals, and they send these signals back and forth between each other, enabling you to go about your daily thoughts and functions.

And thats more or less the division there! And what may seem even more surprising is the fact that when you see something say with your left eye, the information is sent to the right side of your brain, and vice versa. And the same thing with your hands. The corpus callosum allows the communication of acquired information between the two hemispheres of your brain. Like when you see a word, and you immediately visualize that word in your head - thats a direct result of the two sides of your brain working together!

Now, corpus callosotomy itself involves the complete  or partial severing of the corpus callosum. Which may sound barbaric and on par with a lobotomy, but its actually very beneficial to some patients. The most typical circumstance for this surgery is when the patient is suffering from epilepsy (may seem extreme, but let me tell you, seizures are not fun!), and is usually only used as a last resort. Since, as I mentioned previously, the corpus callosum is the "bridge" between the two brain hemispheres, communication between them ceases or is extremely minimal after the operation. Memory, control, and attention span are affected after the operation, but one can lead a relatively normal life after the corpus callosum is severed.

And the interesting part - after the surgery, if a split-brain patient is shown an image in their left visual field, they won't be able to name the image that they're seeing, since the mechanisms for speech association are located in the left brain hemisphere - but they can draw a picture of it! But only with their left hand, since that hand is controlled by the right side of the brain. (Right controls left, left controls right).

Thats all, friends! Perhaps soon I'll make another both about fun medical things, and hope that people find it as neat as I do (but probably not, haha).


XO