- [Voiceover] If you look a little more into the cerebral cortex, it has quite a few different functions. Now these are some of the more general functions, and we'll focus more on each individual lobe in a second. But, memory storage, you can store memories for years and decades sometimes. Abstract thoughts, the awareness of consciousness, as well as the conscious control of your skeletal muscles. All these higher order thinking, all these actions, are from your cerebral cortex. So we start dividing up the lobes. There's four major lobes. We have the occipital lobe, that's located in the back of your brain. It deals with visual information. Yes, I know they eyes are on the front of your head, but believe it or not, that information's relayed all the way to the back of your brain. That's why if you ever got a bump on the back of your head, or got hit in the back of your head, you might have seen kind of these color blurs or stars. Because the very back of your brain is where you process your visual information. Temporal lobe, over by your temple side of your head. The temporal lobe deals with auditory information. It's the interpretation of the sounds coming in. It also helps deal with the comprehension of the spoken and written language. Now, it doesn't matter what language it is, whichever language you learned, or languages you've learned, when they're written down, or when someone speaks them to you, the understanding of that written language, or the spoken word, is interpreted through the temporal lobe. The parietal lobe. Well, the parietal lobes, they're the ones right on the top of your head, pretty much dead center top. These are the ones that are receiving all the sensory input. Now I have here receiving and interpreting sensory information from the skin. Well, it's more than just the skin. A lot of the internal workings, like your organs and muscles, also send sensory information up the parietal lobe. And then frontal lobe. So right where your forehead is, that's your frontal lobe. This is the part that will initiate more activity, the one that will actually cause your muscles to move. Well, it has responsible for speech. Well, I assumed speech was up in the temporal lobe, spoken, written language. That's the comprehension of it. The actual action of making sound or of making speech, that's because the muscles are moving your tongue, your lips, your throat, so all that muscular control is from the frontal lobe, as well as conscious thought. The idea of who are you, of thinking about what's happening next in life. So all this consciousness, pretty much who you are, is up in the frontal lobe. Now, each one of these lobes, occipital, temporal, parietal, frontal, you're gonna have one of each on the left hemisphere, one of each on the right. So even though we're listing off four lobes here, those four lobes are found on the left hemisphere, but those four lobes are also on the right hemisphere, and every one of these lobes, so both sides, all four types, they all deal in memory storage. Helping deal with some short term, as well as long term memory. So look at this picture, this is a brain. See posterior, the yellow back there, that's towards the back of the head. The anterior term is the front of the head. You can kind of notice that the very front of the brain's been cut off so you can see inside of it. Well, we have our right and left cerebral hemispheres, and the four different colors, that purple, blue, yellow, and green, those are indicative of the four different lobes. Then you have that corpus callosum. It's the only way, really, you're connecting the right and left hemispheres, to allowing for massive information transfer between both halves. Cerebral white matter's inside, cerebral gray matter's outside. So here's the brain intact. You can see your frontal lobe. Now, I said the frontal lobe deals with more activity, movements, deals with speech, 'cause that's muscle moving it for speech, as well as your conscious thoughts, where you're thinking about what's happening. That is your frontal lobe working. Here's your parietal lobe, right on the top of your head. This is bringing all the sensory info back into the brain. It's processing the sensory information, and figuring out what to do with it, how do you interpret. Temporal lobe, auditory, so your hearing. Helps with language, but also deals with judgments. Now, I have down here perceptual judgment. Well, because, when someone perceives something, you might judge this to be a proper action, where someone else judges that to be an improper actions. It's all about perception, how you see it. And the occipital lobe at the back of the brain. Visual information's processed here. So even though your eyes are on the very front, it carries all that information to the very back in the occipital lobe. Now, I know this looks kind of like a funny cartoon here, but let's kind of go through and understand what it is. First off, you notice that the red, which you can see that whole red cartoon, but also the red line going across the brain. That is the very back edge of the frontal lobe. We know frontal is motor output. Well, if it's motor, it's controlling movement. So every little fold, every little indent, and upfold, they all control different things. What this is trying to show you is how much different brain matter, or how much space, is dedicated to each part of the body. So you can see how the head, jaws, lips, face, eye, brow, neck, how that one area is taking up almost a third of the entire brain. Look at the hand. Thumb, fingers, hand, wrist, how much that takes up. But then in comparison, look at the elbow, arm, your entire trunk, and your hip, takes up less space than just the hand. Well, why is that the case? Well, let's think about it. How many different movements can your hand and fingers perform? They can really move a lot of different ways. But how many different ways can your arm, elbow, trunk, or hip move? They're quite a bit more limited. Therefore, they have less musculature, not as much movement. So the more movement, the more musculature, the more precision you have in movement, the more area in the brain it takes up. Well, the other side, the blue, that's on the parietal lobe. That's your primary somatosensory area. This is where all of the sensations come into the brain from. You can see how, again, the head takes up a large amount in comparison. The hand's large. That's because they have more sensory receptors, so they have more ability to bring in sensory information. Elbow, arm, neck, trunk, hip, they can still receive sensory information, but they are not as keen, or as sensitive, as the face and hands. Now, if we dive a little deeper down into the brain, we come to this limbic system. The limbic system is referred to as your emotional brain. It's where all your emotions originate. It's where some basic behaviors start. So we have a lot of different neural structures coming together. They help to create your emotions. They help to give you motivational drive, so if you're driven to complete something because of some aspect. Well, that gives you motivational drive. The structure, the hypothalamus, now we looked at that before. That's just above the brain stem. So the hypothalamus is gonna be the gateway. It's how things get into and out of the limbic system. So your emotions, like fear, anger, sorrow, love, now you can go on and on, there's dozens of emotions. Basic behavior, seeking food, satisfying thirst. If you're hungry, you're gonna look for food. The limbic system's controlling that. Satisfying thirst, the limbic system again. And think about it, if you're really hungry, are you in the best of moods? Not typically. So that's a lot of times how it goes with the hunger, or seeking food, with emotions, they're linked together. But the limbic system also deals with sexual gratification. So the feelings from sex go through the limbic system, those emotions from sex. Now, all of these behaviors, though, are not released straight from the limbic system. If they were, the emotions would be too raw, they'd be causing too many problems. So, a lot of these basic behaviors, even some of the emotions, are modified by the cerebral. Modified by the larger brain. They can help to either enhance, or to mitigate, what's occurring. But the limbic system also deals with your short-term memory. So those short-term things, what happened five minutes ago, what happened an hour ago, that short-term memory is also functioning through the limbic system. So everything in green here is the limbic system. You can see how you have some towards the front, or anterior portion of the brain, and also some towards the back. It spans all the way throughout. The cerebrum is the whole outside covering, thalamus is dead center in between. Corpus callosum's also in the middle, but the limbic system is forming all around them. The hypothalamus, let's point out there in kind of that purplish-blue, that is the entry and exit point for all the information into and out of the limbic system. So, how do you store this short-term memory? How do you get the information back? Because sometimes you can remember exactly what you did one hour ago, other times you look back and say, "What did I do 10 minutes ago?" It depends on what was important, what was occurring at the time, and how much has occurred since then. But your short-term memory is your working memory. Usually it's just the past couple hours. It's stored there in the limbic system. So if you remember something from 7:00 at 10:00, well, by the time you hit 11:00 or 12:00, that 7:00 information might already be gone. Only a few hours of information can be stored. If anything is deemed important enough, than that information can go into your long-term storage. Now, long-term can be from a day or two ago to many years ago. Now, this long-term storage actually will change neurons and synapses. It puts them in particular patterns, particular orders, to be able to store this information and keep the information present. Does that mean you'll never lose your long-term memory? No, sometimes over time long-term memory fades. But we definitely have distinction between short-term limbic system, long-term changing the neurons. Now, long-term still involves the limbic system, though, just not the same way the short-term does.