Health and medicine
The nervous system's functions are divided into basic and higher categories. Basic functions, performed by the central and peripheral nervous systems, include motor control, sensory detection, and automatic responses. Higher functions, carried out by the brain, encompass cognition, emotions, and consciousness. Understanding these functions helps identify syndromes, or patterns of abnormalities, in neurological or psychiatric disorders. Created by Matthew Barry Jensen.
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- Are we even certain that consciousness exists? I mean, we're aware of ourselves, but then a combination of cognition and emotion would explain that pretty well.
Unless consciousness is the difference between being awake and dreaming?(17 votes)
- Being responsive to stimuli is one definition of consciousness and I don't think that is what the speaker is referring to in this video. He is referring to a phenomenon that we believe to be uniquely human whereas being responsive to stimuli could be applied to most any animal (and actually in plants as well). Philosophers have been trying for centuries to define consciousness and determine whether or not it exists. In response to the original question, I suppose we do not really know anything for certain, but I think that consciousness is related to being aware of our cognition and emotions. For example, our ability to think about thinking.(31 votes)
- why aren't there any nerves on the face/cheek??(8 votes)
- What category is dreaming in?(10 votes)
- Will it described as "autonomic" rather than automatic in the 3rd category of the basic functions of the nervous system?(7 votes)
- Why is it difficult to define conciousness?(6 votes)
- Consciousness is difficult to define because it exists in more than just the purely physical sense of which science is used to defining. We can't really touch it, we can't see it, we can't feel it, and we certainly can't define it. This is because consciousness, at its core, is more than the mental awareness of the person, the ability to respond to stimuli, to have coherent thoughts, to understand their location, to know who they are and what they are doing, to respond to stimuli, et cetera. It's extraordinarily difficult to define but easy to understand. May I also add that your conscious mind is reading and understanding this? That's one of the great can't-pin-it-down's of neuroscience.(9 votes)
- Where can I find the "parts of the brains"?Do you have a video of that?(7 votes)
- They have an overview on the brain and videos dedicated to some major parts of the brain like the Cerebral Cortex, the Brainstem, and the Cerebrum. They don't go over each and every part of the brain in detail though.(3 votes)
- Isn't it called the autonomic nervous system? I understand that it regulates functions of the body that we do not voluntarily control. But in the video, he called it the automatic nervous system and this confused me a bit.(5 votes)
- It is called the autonomic NS, and autonomic pretty much is synonymous with automatic. I'm very sorry that confused you.(6 votes)
- how do you keep your balance?(4 votes)
- The cerebellum in the back of the brain is responsible for balance and motor movements. The cerebellum of the brain is located near the brain stem.(7 votes)
- Around2:21what does the narrator mean by "tone?"(4 votes)
- "Tone" is the resting tension of muscles. It can be seen with how much mass a muscle has, or how stiff it is.(5 votes)
- I thought that not all of the skeletal muscle was attached to the skeleton? The muscles like the ones to push food down the esophagus is a voluntary action and I don't think that those muscles are attached to the skeleton. Are all smooth muscles not attached to the skeleton?(3 votes)
- Smooth muscles move food through the digestive tract, change the size of blood vessels and the size of the airways, for example.(5 votes)
Voiceover: In this video, I'm going to talk about some of the functions of the nervous system and how I think about these functions and have organized them in my mind. The nervous system performs many functions that allow a person to experience their life and which create their behavior, as well as many necessary functions of the body, for which a person is usually unaware, and these functions can be categorized in different ways. The way I like to think about the functions of the nervous system is first to divide them into two big categories that I think of as the basic functions of the nervous system and the higher functions of the nervous system, and you could use whatever words you wanted here. You could say the lower functions and the higher functions or the basic functions and the complex functions, but the reasons I like to use these words is that the basic functions aren't really that simple. They're actually fairly complex when you start to get into them, and they're not really lower in any particular way either. Really, you need the basic functions and the higher functions. Now, dysfunction of different parts of the nervous system may cause different patterns of abnormalities of the functions of the nervous system, either the basic functions, the higher functions, or both, and patterns of abnormal functions we call syndromes. Let me just write that word down, syndromes, which means patterns of abnormalities, and certain syndromes involving abnormal functions of the nervous system are more common than others, because they're caused by neurological or psychiatric disorders that occur more frequently. The basic functions of the nervous system are performed by many parts of both the central nervous system, which is mainly the brain and the spinal cord, and the peripheral nervous system, which is mainly the nerves. When it comes to the nerves, the cranial nerves primarily perform the basic functions of the head and the neck, whereas the spinal nerves primarily perform the basic functions for the limbs and the trunk, because that's where those nerves generally go. Now, I like to divide up the basic functions of the nervous system into three big categories. The first category I would call motor, and the word motor, in this context, refers to control of skeletal muscle. So, skeletal muscle, the main muscle we have that's all over our body and attached to our skeleton, and by controlling skeletal muscle, the motor functions of the nervous system cause movement, tone, and posture, which are the end results of contraction of skeletal muscle. The next big category of basic functions of the nervous system I like to call sensory functions, and this involves all of the senses, basically anything that the nervous system can detect. And we're used to hearing about five senses, but it actually turns out that if you kind of split them up into finer categories, there's way more than five senses. There's vision, there's hearing, smell, taste. There's a sense from the inner ear, called vestibular sense, and there's multiple senses of the body, called somatosensation, and somatosensation includes the senses of touch, the position of body parts, vibration, pain, temperature, and several others. And for each of these categories, we'll get into a lot more detail on these in later videos, because there's really a lot going on within these categories. And the third big category I think of, when I think of the basic functions of the nervous system, I like to call automatic functions, automatic, and these are things that don't require conscious involvement, and that includes a lot of different things, like reflexes, like when your doctor taps on your knee at the clinic, and your leg kicks out without you telling it to, and there's all sorts of different reflexes of the nervous system, and we'll go over a few of them in later videos, but there's also all sorts of other kind of automatic functions the nervous system does without requiring the involvement of consciousness, including control of a number of the body systems involved and really important things like circulation, respiration, and digestion. So, more on that later too. But now, the higher functions of the nervous system are not performed by huge areas of both the central and the peripheral nervous system. The higher functions are performed by parts of the brain, and like the basic functions of the nervous system, I like to divide up the higher functions of the nervous system into three big categories. The first big category of the higher functions of the nervous system I like to call cognition, cognition, and people use this word in a number of different ways, so it can get confusing when you're reading about cognition, but I like to think of this as kind of the thinking functions of the brain, like thinking, but there's also a whole bunch of other things that we can often put under this term of cognition, including things like learning and memory and language and a group of things we call the executive functions, which involve creating goals and organizing behavior to achieve those goals. So, more on that later, because there's plenty going on there. The next big category of higher functions of the nervous system I call emotions, and emotions, of course, are our feelings, but it turns out there's a lot more to emotions than just kind of what we feel, because emotions play a major role in our experience of life and a lot of other functions of both the nervous system and the rest of the body. And the last category I like to think of under the higher functions of the nervous system is consciousness, and consciousness is a really tough word to define. I don't know that I have a great definition, because people have been trying to come up with a definition everyone can agree with for quite some time, although we all sort of know what consciousness is. The best I can probably come up with is that consciousness is related to the awareness of being a person, of experiencing one's life, and controlling one's actions, and while there's a lot we don't understand about how the nervous system does pretty much all of these functions or categories of functions that I've written out here, consciousness is the one we know the least about, where many many people are doing lots and lots of research to try to understand how this phenomenon of consciousness is created by the nervous system. So, this is how I like to think about the functions of the nervous system and how I like to break them up into some big categories, and like I said, we'll go into the details of lots of these categories in later videos, and if you look in different textbooks and things, you'll see people have organized the functions of the nervous system in lots of different ways, and in some ways, it doesn't really matter how you organize all the different functions of the nervous system, as long as you find some system that makes sense to you, to keep track of it all.