 Hey everybody, Dr. O here and this favor is going to cover some of the key structural parts of the outside of the brain here with the cerebrum just so you anatomically know where they are. We'll talk more about function later. So as we said in the last video, the cerebrum is the largest part of your brain controls anything that's conscious, anything you're aware of the fact that I can feel things or I'm initiating the movements of my hands. That's all conscious stuff, which means it comes from my cerebrum. Everything below the cerebrum would be subconscious that you've probably heard that term before. So the actual cortex itself, you'll notice that it has all these hills and valleys. They're there for surface area. If the brain was smooth, we would have profound mental problems. This is the only way that you can cram 100 billion neurons into such a small structure is to have this massive surface area. So you see that the little teeny valleys or depressions there would be called a sulcus or a sulci would be the pleural. The hills or these ridges would be called a gyrus or gyrie. And then if you do have a deep groove called the longitudinal fissure, which I'll show you in a separate video here. So I've already told you what they do. They allow you to have more gray matter to have more neurons. Okay. So as far as let's let's go ahead and look at speaking of gray matter versus white matter. Here's a slice of a brain, probably from a sheep or something. But so gray matter on the outside, white matter on the inside. So I'm obviously grow gray matter is the name of the name of the channel. But the gray matter is where information is processed. So when you think gray matter, think informational processing. That's where the cell bodies of neurons are. White matter, think transportation. White matter carries information to and from your parts of different parts of your nervous system. White matter is white because it's full of fat and fat and the fat is white. And that's because the axons here that are traveling to and fro are myelinated and they're covered with fat. So that's why it's white. So gray matter thinks cell bodies, information processing, white matter, think fat for myelin and think of carrying information. So gray matter is located in two places. We primarily think of it in the cerebral cortex here on the outside, but it's also located inside the brain in an area called the basal nuclei. We won't talk about them much, but just so you know, there is some gray matter like the, you see the caudate and the butamen, those are examples of gray matter inside the brain as well. So that's gray matter and white matter. Here we see that longitudinal phasor I was telling you about. So that deep groove in the middle that separates the right and left cerebral hemispheres. We'll talk about the corpus clausum and the internal structures that connect them in another video. Here we see the actual names of some of these valleys and ridges and why they're important. So to me the most important one is the central sulcus right there because it divides the frontal lobe from the priatal lobe. And the frontal lobe is where you have your primary motor cortex. It's called the pre-central gyrus of the frontal lobe. And the priatal lobe is where you have your primary sensory cortex. It's the post-central gyrus of the priatal lobe. So the central sulcus is the most important one to me here. Then we see we have the lateral sulcus. It separates that frontal lobe from the temporal lobe. The parietal occipital sulcus separates the parietal lobe there from the occipital lobe. Then one area you can't see and I actually don't have a good image for you anywhere. But there's an area called the insula or the insular cortex. Insula means island and it's going to be basically inside underneath that lateral sulcus. If I were able to peel the frontal lobe and the temporal lobe apart, there would be an area called the insula or insular cortex there on the inside. All right, that's everything I had. Like I said, I wish I had a good picture of that. But that is an important lobe. We'll talk about what these lobes do in the next video. I hope this helps. Have a wonderful day. Be blessed.