This one was by request and I was sure this had to do with a surgically implanted wearable poop bag. Glad I misread.
Today’s Moment of Science… the corpus callosotomy.
The history of treating epilepsy is fraught with mistakes, bad decisions, and a buttload of yikes. “Excess phlegm in the brain” was theorized to cause the disorder at one point. Exorcisms, medicinal herbs, and bloodletting were all traditionally used. Trepanation, i.e. drilling a fucking hole in your brainbox, was employed from time to time. Most successfully, fasting was used as far back as 500BC. But fasting- as in a complete absence of calories- has a firm time limit before you find yourself looking at the beloved family pet and considering a seasoning mix.
In the early 1900s, it was discovered that an extremely strict low carbohydrate, high fat diet could manage epilepsy. It manipulates the body into some of the same metabolic processes that happen when fasting, specifically the production of ketones. You could now eat something without seizures, which was a drastic improvement.
But also cake is delicious. So when anticonvulsant medications came around, people were happy to ditch the bacon wrapped butter butter sandwiches. Anticonvulsants, along with several other medications, safely and effectively manage most seizure disorders today.
Not all cases of epilepsy are created equally easy to manage though. When you’ve tried and failed all of the above, somewhere a neurosurgeon hears a choir of angels singing and fetches their favorite scalpel.
The corpus callosum is a nerve fiber bundle that connects the two hemispheres of your brain. Dr. William P. van Wagenen was the first to attempt cutting this connection in February of 1939. He noticed tumors that broke the connection between hemispheres led to a reduction in seizure activity for his patients with epilepsy.
I’m just glad the reasoning was a little more complicated than “have we tried unplugging the brain and plugging it back in?”
In his pioneering 1940 paper on the subject, he reported results from ten patients he’d performed those first corpus callosotomy procedures on, all of whom experienced improvement or cessation of their seizures, seemingly without detriment to their faculties. However, van Wagenen has been relegated largely to the footnotes of history for this procedure. It’s unclear why, but he was said to regret what he did, having compared it to butchery.Luckily, the callosotomy wasn’t left to the history books.
It was further researched first in smaller animals by Roger Sperry in the 1950s, concluding that it was safe and helped with seizure activity, but it was producing some interesting cognitive changes in cats.
Then shit got really wild.
In the 1960s, Sperry figured he should have a few chats with the patients with split brains for funsies. Because if it’s making cats act strange, what the fuck is it doing to humans?
Talk to someone before and after a callosotomy, and you can’t tell they’ve had the procedure from their general behavior.
(Most of it.)
Then place an object in their left field of view and ask them what it’s called. You won’t get a word out of them. Place the same object in their left hand with them blindfolded, still nothing. If you ask them to pick the same object out of a group of items, they’ll be able to identify it by touch, but the language center is stuck worse than that goddamn boat in the Suez was.
Now place that same object in their right field of view or right hand, and no problem, they’ll tell you what it is.
Language is processed, largely, in the left side of the brain. So while sensory information like touch and vision from the left side of your body is processed in the right hemisphere, you can generally only dig vocabulary out of the left hemisphere. In many ways the hemispheres are operating like two separate brains now.
Patients have reported their left hand and their right hand fighting against each other. One hand will start to pull the pants up and the other hand, just being a free thinker, will put up a fight for the sanctity of no-pants Wednesday. Being of two minds comes with complications. Post-callosotomy patients have said re-learning to do certain tasks with their hemispheres working independently is a pain in the ass, but the surgery is life changing.
The scope of knowledge gained from the surgical patients who volunteered to be studied shifted our understanding of the brain drastically. Sperry was awarded the Nobel Prize in physiology in 1981, for his “discoveries concerning the functional specialization of the cerebral hemispheres.”
I might eventually not pronounce this the same way as the poop bag thing.
This has been your daily Moment of Science, reminding you that most pop psychology books about the right and left side of your brain are utter bullshit.
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