Oh this lecture video is going to be on a brain and cranial nerves so again let me get some PowerPoint you you you okay so this is the other half of deep central nervous system remember central nervous system or CN NS has two part spinal cord and brain so we already discussed the spinal cord and in detail hopefully watch that video over and over come to now we're going to talk about brain okay it is obviously one of the largest organ the body it's weighed like three pounds you don't feel it that you have like three parts right there and walking all day long on three bumps on your head back there are some other reason egg why do you feel that because it's like it's kind of floating in CSF cerebrospinal fluid which I won't mention literal okay so brain controls your sensation they have memory motion decision-making AVR all these things controlled by a brain this is the most upper and complicated level of your complete thought process so there are regulatory process in other words this is the outer structure so in order to understand the brain really well basically you have to first go to the embryonic development stage going there but before we go a couple of simple thing that I'm going to mention here is unlike spinal cord where gray matter is inside and outside is like white matter here the outside part is the white matter meaning most cell bodies that's why I deput inquiry and if you want to see the some white tracks it should be inside the brains of you if you cut it open if you make a like a sagittal section the brain then only you can see that okay so these are up send downs of deploying those are the up region is up area or my pointer is right now is called gyrus join us as the world gyrus is singular gyri is hello okay and the group this group on the shallow part it's called sulcus that is the word sulcus or the pure will be Southside this humongous part which is like almost like eighty-three percent of the brain volume so this humongous part is considered grow that's a lot Sarah and this is Sarah Ella this is cerebellum the bottom most part right here this is you can call it brain stem with a different part of the brain stem you can see the entire brain stem starting from here if you open the bridge so if we go back to the previous picture you can see brain stem up to here so that's brain stem commonly known as okay and this is cerebrum this whole big thing and this is cerebellar then the main part of brain like only to a new study the function of the brain as well as structure even deeper than a Tamiya to understand this is the cerebrum then this portion right here in Columbus and right below this is hypothalamus together this area we can tally encephalon diamonds through so diencephalon so this is basically a relay Center where all the information goes up to the prey and all the information come through there okay then this region like starting from here all the way down we call them brainstem brain stem as midbrain middle portion of the print and the pons that you can remember and to is is like a letter P right there or plants it means bridge like this pons it's a bridge so that's the bridge between the lower part of the brain and the upper part of the brain and this is medulla oblongata medulla means inside so if this is the outside all the way inside is this dependable means rectangular so this is the middle of longer than say the rectangular inside area and this is cerebellum right could be attached at the bottom of the frame right there it looks like a like a nice mouth piece of broccoli attached that's the cerebellum okay so now how do we approach this chakra the chapter you're going to approach actually you have two things to study okay well okay three things to start so basically you need to know the anatomy very well so when you go detail anatomy that's your lab portion of the study and now in this part you are going to know the different parts of the brain and their function as well as 12 pairs of cranial nerves so 12 pairs of cranial nerve singing that's remember 31 pairs in case of spinal cord here 12 years so 12 pairs of cranial nerve known as like C and one cranial nerve one one Roman numeral and C until creamy alert to CN 3 thin yellow 3 and so on but those have specific name such as cranial nerve one is all packed arena cranial nerve to is optic nerve cranial nerve three is oculomotor nerve cranial nerve or is trochlear nerve cranial nerve 5 trigeminal nerve cranial nerve 6 abducens nerve finland 7 facial nerve cranial nerve 8 vestibulocochlear nerve pineal nerve 9 glossopharyngeal nerve cranial nerve 10 vagus nerve cranial nerve 11 accessory nerve and cranial nerve 12 is hypoglossal nerve so what I did I put a separate document by saying all this cleaner I just saved that I decided at length all these connealy nerves their name their time because north can be three types we know one is called a donor one is called sensory nerve to motor nerves bring out the information censoring of bringing the information and another is the mixed mixed means that nerve has both kind of trapped so subtract going in that will sensory some trapped coming out in smaller together we call mixed now so nerve those are the three types of nerve sensory motor and mixed so all these twelve pairs of now some of them are sensory some of them are motor and some of them are mixed so you need to know that and then obviously their function and what happen it that get damaged so a for example just a simple one so all factory nerve so that is a sensory nerve because this brings in the information is right here on the load it brings in the information to the brain which is known as cranial nerve one and so its main functional smell so obviously if it is damaged you are not going to have smell so that means you have impaired sense of smell so that's how you have to memorize so you have you ever smell so impaired sense of melts when the olfactory nerve is not working and so on so what I did I made a chart I made a chart for you the entire table is posted as well so so mom if you if you whenever you get a chance you download that and memorize that chart that is extremely important and that needs some writing and that means some reading so I would recommend you read that and then take a piece of paper and write that over and over at least two to three times because not wholly or really meet that for your lab practical but also you'll need to go to need a lab quizzes and but also we are going to meet that for lecture exam for so in the lectures are all you are going to get at least three to four minimum of three to four questions from that area only so this like as I said it's a simple thing I gave you the strategy I'm you believe you note and now it's up to you so make sure you read that thoroughly and know exactly all the cranial complex of north they are function their time in detail ok and I'm going to mention of them a little bit in this lecture as well ok so Sony so we only study the structure of the brain the first thing that we should study is the embryonic development of the bird so what does that mean that means how the brain is formed so initially our our nervous system will begin with a neural tube like this so like this let's say this is a new multi don't that - if this neural tube has to grow they will grow this way in this way you draw on the side says that God it's like a tree so when you plant it a tiny or one like a tiny plant and when it becomes a tree it goes it goes all the way that it goes on the top of those the hood goes down it becomes bigger so this new world - if you look at this neural tube then it become like this my arm so it becomes like big 12 but here is the problem the problem is when this is happening at the same time the skull has formed that our skull has formed so then this new route you would you want to grow does not have room so they are basically stuck right here and it becomes in my opinion like a bone saw meaning it does not go this way it becomes like this and that muscle head that you see that's basically this so that could not grow because your skull is very strong should they become like a mushroom so this is the top part so called the brain that we are talking about this is the bottom part of way and so where is the middle one middle party cannot see because it is kind of on top of this so this is the middle portion the top part is covering so in order to see this you have to remove this order to come so if we carry on the side or is like a sagittal wait then this is the middle part that you can see so you can see the top or you can see the bottom part but the middle part is kind of heated so when you instead it is embryonic development so one more time so the neural tube now couple names the roster per the word roster means towards the nose and word quite an or postilions towards the chin so basically what happened you know we studied the brain in like a rat like a rodent model all the time so that's how the name came and we continued but he can call this like a roster site means towards the towards this side and the quadrants that means toward that side you can't think that way so the rostral side or the anterior side they become pros encephalo close in settle on and then Mason Mason means middle to mesencephalon suppose encephalon for break the top part that mesencephalon is basically the middle portion of the brain and ramen or the tail part the talons rhombencephalon - telly telly tell part is basically the hind part of it the bottom portion of the bridge so that's a top portion of the brain that's a middle portion of the brain that's bottom puttin out the top person when they're growing they become telencephalon and diencephalon so these are protein Cephalon now bifurcated into tellen and diencephalon the telencephalon eventually becomes cerebro so the telencephalon eventually become that cerebrum so I have a brain motive right here so so this is the part so this part this is the telencephalon this is the terms of dying this is becoming cerebro okay so now the diencephalon you can only see if you open that part so you can open that part this portion is like a diencephalon the middle right here the middle portion that's is the diencephalon so diencephalon are all these telomers hypothalamus and epithalamus area so this is like a thalamus area this is hypothalamus area and epital of us is the top previous these become the diencephalon so this Airy Brunt become the telencephalon become the cerebrum diencephalon become the thalamus then this portion right here detail be able to learn later on the other to me this portion right here that's the mesencephalon which becomes the brain stem or maybe portion of the brain and then comes a whole bottom part like this whole section of the bottom part so that basically mitten and my lens have a lot so mitten Cephalon become brain stem or the pons and the portion and the cerebellum so this is the pons that region is the pons and this is cerebellar this - that's mitten Cephalon and myelin Cephalon this portion which has become spire middle oblongata and followed by spinal cord all about spinal cord okay so that that is basically the from the embryonic structure how we get to the full brain beast it has to be near head otherwise it can't really follow this chapter so the neural tube when they're growing up they have no room just remember but they become like a mushroom head that is the top part so that's basically it is that such as I just showed you that's silly silly prom and then right underneath it is all the thalamus hypothalamus and epithalamus area that's a little really center mainly income the brainstem of the midbrain portion then becomes pons and cerebellum and finally metal so now when you're approaching to leave this chakra you basically need to know cerebrum diencephalon brainstem like midbrain portion pons cerebellum and medulla oblongata what they do what is their function in recap okay they're going to go there but we put there this is basically exactly the what I just said is right here so this is how we're going to study them in detail but before that there are two other aspect of the brain number one the brain has been trickles ventricle means chamber number two about cerebrospinal fluid the fluid that circulate the tawny brain but also spinal cord now being bring like bring like this spinal cord also covered by mini jizz is exactly the same way we learn in spinal cord meninges a same as spinal cord meaning they are three layers in diameter arachnoid mater and fireman so fire murder adheres close to the brain then next is arachnoid mater and then outside is the strongest one is like a tuba matter it's same layer of many days they can be on the brain and the brain and the spinal cord so this layer if you imagine this is your layer that goes around in the brain and then continue to the spinal cord okay the same covering been through tons of debris rain has four ventricles the word ventricle means chamber it has four chambers now when you look at the city from when you look at the Senate from one more time I'll show you the model when they look at the cerebrum this is the humongous cherrybrook they have literally a huge fissure a long crew that did that actually died that actually break this data to create the two parts of the cerebrum we call them hemisphere so this is a one hemisphere or right here it's the right hemisphere and the other half is the left hemisphere so brain the cerebrum has two independent area these longitudinal fissure which runs so right in the middle that actually divided the cerebrum into two independent hemisphere same thing here so when you're looking at this cerebrum this is one hemisphere that one hemisphere the reason I'm mentioning this because one ventricle is right here the other ventricle is right here instead of calling the 1 & 2 or 1 & 2 we just call them lateral ventricles so lateral ventricle of the left hemisphere lateral ventricle of the right hemisphere so we have two lateral ventricles then right in the middle right in the middle we have a third ventricle now third ventricle and lateral ventricles they are connected but two lateral ventricles within them they don't have connection so they are connected through the third ventricles this tiny aperture like a tiny hole that's called ETA ventricular for our men for amendments hole in a bone chapter we learned that so interventricular foramen that opening right there should they connect lateral to the third they can--it lateral to the third again now then third suit we have three already so two lateral ventricles and well third then there is a pipeline that's called cephalic aqueducts mason mintz middle or you can call cerebral aqueduct cerebral aqueduct or mesencephalon aqueduct that connect this third ventricle to the fourth ventricle so forth when trickle which is actually at the base of cerebellum that's the our number four ventricle so we have two lateral one third one fourth ventricle and then that continue to become central canal of the spinal cord yes our four ventricles so our four ventricles are two natural ventricles one third ventricle one one fourth ventricle two lateral ventricles are not connected they are connected through the third ventricle using the opening called interventricular foramen pyrrole will be intraventricular for a minute and then this is med encephalic aqueduct or cerebral aqueduct which connects third and fourth ventricle then fourth ventricle continue in the spinal cord become the central canal of the spinal cord so what is in the ventricle inside the ventricles he have cerebral spinal cord there is commonly known as vivid form is like CSF cerebrospinal fluid so voluntary spinal fluid meaning that fluid is in the cerebral which is our brain as well as in spinal cord so they're approximately eighty two hundred fifty hundred 60ml but every day body is producing almost close to 500 ml upset it was spinal fluid so the fluid mainly comes from the the to the blood-brain barrier from the blood and then we maintain the particular amount of glucose proteins and ionic parents who just basically has a tremendous function for all the nerve cells and supporting cells so what they do they have three distinctive functionality mechanical protection chemical production and circulation so obviously nutrients and waste products are going back and forth remember we learned that astrocytes they create the blood-brain barrier so the blood directly has no contact with the nerve cells this is the contract cerebral spinal fluid is the contact between them so they get the nutrients delivered to the nerve cell and they take the whisper of breath the blood stream then obviously chemical protection referred to that they create an ideal environment so that the nerve cell can work best to produce carry the action potentials or the signals between them and finally mechanical protection remember at the beginning I said be about three pounds weight or breathe like a nerve tissue you don't feel it he feels like 50 grams like instead of 1.5 kilogram the pounds feel like 50 grand why because it is like floating in the CSF it is floating in the sea so for example like if you want to if you want to pick up somebody you know in land that person could feel like really heavy but if you both are in the swimming pool or in a lake and if you want to pick up that person in the swimming pool you feel like very light same thing it's called Wannsee so basically that cerebrospinal fluid think they're they're everywhere the brain is floating in there so not only they are you know protecting the brain tissue because all these nerve tissue other is going to be damaged if you're a three-pound sitting on the top particularly the lower portion but also when there is a you know impact comes onto the skull that softens down to these CSF that softens down to the CSF so the brain does not get that much mechanical damage okay so sherry for spinal fluid has a lot of function this is the summary mechanical protection chemical protection and obviously circulation now where'd they form and how the circular these are the two things we need to answer to where they form they form in the ventricles they form mainly in the ventricles one because in the ventricles there are some modified ependymal cells ependymal cells one of the supporting cells in the CNS and these are modified because they create a network of colorful cells is that so it's called choroid plexus plexus means network or oeid means colorful to all the blood capillaries covered by the ependymal cells and where are they we are in the lateral ventricles there for carpentry tell them the whole vertical so the ventricles they have these things and that's why they're making our lots of CSF as I said we can make as much as like 500ml of CSF but everything absorb all the time so almost 150 160 ml circulating throughout your spinal cord and the brain all the time the question is how do circulated this is how they circulate so I think this is the better slide that this is how the circle it meaning she is a former in the lateral ventricles we just learnt they go through the interventricular foramen ER from the third letter to the from the lateral ventricle they come to the third ventricle card is in the middle that relates on the side in the two hemisphere so they come in the third ventricle then from the third ventricle to the aqueduct which encephalic equator or cerebral acquitted they could be the fourth ventricle therefore can't result from there is also two aperture like two opening like lateral and medial a purchase I don't have a picture for it it should be right there so those aperture allowed them to go to the subarachnoid space and then subarachnoid space they go around the brain and the spinal cord everywhere and finally they go to the venous blood this part we are going to learn in a and B tube so venous blood being on the vein they collect the blood they go take that blood to the heart and then the heart send that blood to the lung so that lump you defiled and purify me they get rid of the carbon dioxide they put oxygen back into the blood that blood come back to the heart again that's why it said heart and lung and then it goes to the artery and when they pump into the artery that artery branches into the brain and they bring it to the correct axis again so this part obviously whether how brain artery heart lung works you don't need to know detail because that is mp2 material but right from here you should know from all the ventricles plexuses the CSF goes to the corresponding respective pen to them and then that's how they travel so CSF what is CSF what is their function and how they travel these are the three things you know as well as the ventricles octave a break through their four ventricles to stack now let me explain first how these slides how I did this slide of the remaining one remaining one is I'm going to go through with you but it is a really simple way I designed it right here so I started from bottom of the brain to the top so we are going to learn me to love longer if you like constant like a midbrain and then thalamus is and then the city back this way because the lower part of the brain to learn more autonomic function autonomic function when even I have any conscious control on that and the more you go to be a more complicated functions like memory motion music language all these complicated things come right here so we are gonna start from the bottom so this the slide when you see these kind of picture that green area representing me to la Blanca that this is what a little study right now so medulla Blanca recipe said this is the summary part so as I said he says all autonomic function so basically there are five cranial nerves 5 of them 5 2011 12 11 10 9 and 8 this 8 through 12 these 5 cranial nerves are in the middle of like that and there this area this area mainly due to cranial nerves we are going to talk about individual functional bit later but this is you know they are mainly cardiovascular and respiratory set the main can also reflect Center for scuffing which is amazing swallowing etc but this is really cardiovascular and respiratory what does that mean and in this area control your heart so that heart when they're pumping the blood goes to the artery and then the kulluk back with the green that pumping as well as the a matter of the blood vessel that control is right here cardi restless and how they do it to not it you know because that's the NP - so cardiovascular center is located at medulla oblongata meaning that is the area they control your heartbeat and obviously our movement of the blood to D blood vessels they also have a rhythmic area for the respiratory Center like basic breathing like inspiration exhalation inspiration excess it that's basic breathing rhythm that's here but ponts has a little bit extra work on so on the respiratory Center and apart from this fire premium lab so now basically we are going to talk about those buy premium nurse so these is right here in the middle of Vanguard those 5 cranial nerves you're going to talk about as I said 8 through 12 all the like 12 11 10 9 8 those five that so basically what you need to do you can refer to that chart again that I discussed with you earlier that chart has the detail of cranial nerves go back there and study them again so this is the last one called high for class although the number 12 high populist anger hypoglossal nerve they are more alert - lesson and they're more alert so they are made controlling to control what control muscles for speech so if you're hypoglossal nerve cannot function properly you will have an impaired speech by the way there are a lot of other nerve also involve you but this is the main