So welcome back to the Brain Boost channel. Today we're going to be talking about the split brain syndrome and the cause of that, how that arises, what that means for someone with split brain. So let's just jump right into the video.
So just to put everything into context for you, when we're talking about split brain, we're looking at the cerebral cortex, which is where information processing occurs, and there's something called the corpus callosum. which is a nerve fiber bundle that is found underneath the cerebral cortex, and it's going to connect your left and right hemispheres to each other, right? So it's kind of like the relay center, the highway between the left and right brain, and it transfers information between both to the other.
So if you were to sever this, it's as if your left... Side and your right side of the brain cannot necessarily talk to each other. So that's what split brain is.
It's when you have damage to your corpus callosum or if it's severed for whatever reason. So a common, or maybe not so common, but an example of severing the corpus callosum would be during epilepsy. An epileptic might get a seizure.
that starts in one part of their brain and it travels to the other half, which will exacerbate the seizure. So if you cut or you sever the corpus callosum, you are basically preventing this information to pass through to the other side of the brain. So that is supposed to help with epilepsy. So just to present another form of imagery so you can see what I'm talking about. If we slice into our brain here, we can see the corpus callosum right there in the middle that is transferring information between both hemispheres, the left side and the right side.
And something that you should notice or remember is that there is some localization of a function in the left hemisphere and the right hemisphere. So the left brain is controlling speech for the most part. Right brain is controlling perception and spatial relationships.
So we're going to see how these two functions play out when someone is split-brained. So here's another visual for us to better understand and get a little more background information on split-brain syndrome. So as you can see, the eyes are a little bit more complicated than we think when it comes to our visual field. In that we have hemifields. So our left eye for example technically has a right and left hemifield that get processed and it crosses over and it also feeds back into this side here and the same thing goes for the right side.
So one thing I want you to see is that we have the corpus callosum here which we are going to theoretically sever and we're going to see what happens when we do that but something you should remember is that the brain is contralateral. So the left hemisphere of our brain technically controls our right side, and our right hemisphere of the brain is controlling our left side. So let's just see what happens. Okay, so this is an example of split brain.
So let's just see how this goes down. So we have a patient, and we ask them to look at this line in front of them, okay? If we were to ask them... What did you see? Okay, and we put a baseball image there.
Remember, the left side of the brain controls speech, the right side controls perception, spatial relationships, and we have a contralateral brain. In this case, the patient is going to say, I saw a baseball. The left side is processing the information, and he is saying, yeah, I see a baseball, because that is the speech side. Control of speech is the left side, right?
If we put a screwdriver here and ask them to pick it up, they're going to pick it up. And it's because the right side, which is in charge of perception and spatial relationships, is processing that information. So he's going to pick it up, right? Remember, we have a contralateral brain.
So it's telling you to pick it up. The right side of the brain controls your left side of the body. So that's why he can pick it up. and the information is being processed on the right.
Now, if you put a screwdriver here and asked him, what did you see? You're basically, this is being, you know, processed by the right brain, and the left brain is what is in charge of speech, and the right brain is in charge of perception and spatial relationships, if we remember correctly, right? So he's gonna say, I saw nothing, I- don't see anything here as you can see.
He's going to say I saw nothing. So normally what happens someone that isn't split-brained will see that image right they're going to process it and it's going to be sent over to the other side here and then he's going to say yeah I see a screwdriver on the left but he is split-brained so he saw nothing. This is his non-verbal right side and this is his verbal left side.
So That's essentially what split brain looks like. So that's it for today's video. Be sure to subscribe to the channel, like this video, and comment with any questions or any other video topics that you would like Brain Boost to cover and you will see that in a follow-up video.