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Current time:0:00Total duration:6:38

Video transcript

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 kind of organize 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 to 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 want it here you could say that lower functions and the higher functions or the basic functions and the complex functions but the reasons I like to use these words of it 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 a particular way either really that 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 are 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 in 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 it's a skeletal muscle the main so 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 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 somato sensation and somatosensory parts vibration pain temperature and several others and for each of these categories we'll get into a lot more detail on these and 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 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 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 in 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 coggan mission cognition and people use this word in a number of different ways that 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 there's a 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