hey everyone sorry welcome to professor long's lectures in anatomy and physiology i'm professor bob long we've been going over the anatomy of the brain we're going to continue that there's a lot to know and we're not even getting to all of it if you've been watching my videos you know that these videos are intended for use by students who are enrolled in my class if anyone else out there in youtube land finds them helpful or if you are in my class please hit like hit subscribe so that you get new videos i get some good feedback and we can continue to work together this way now what we're going to be going over is the 12 pairs of cranial nerves now if you're in my class we've been covering the external and internal anatomy of the brain on pages 32 and 33 and they're all spread out over two pages and now we're going to be on page 34 covering the 12 pairs of cranial nerves now i've done this in a drawing in lecture i believe and i could also do it somewhat in a drawing in lab but we really got to identify them on the models and we see them on either one of these two models some of the nerves are tiny and they're crammed together so they're very hard to see but we're going to do our best i'm going to set the brain on the half shell aside and i'm going to pull the puzzle brain out i don't need the cerebellum i'm going to leave it off for now it would be back here so if you were looking at it you would be looking at it something like this okay now i'm going to remove the cerebellum only because it keeps falling off all of these little white lines these little white spots or many of them are our cranial nerves there are 12 pairs of cranial nerves meaning i have 12 on the right half of the brain and 12 on the left half of the brain the only cranial nerve that is associated with the cerebrum is this one right here this is called the olfactory nerve for cranial nerve number one i believe we're going to ask you for the lecture test or the lab test to give us the roman numeral and the name so this would be cranial nerve number one you use roman numerals they're also on the list of things to know it's called the olfactory nerve it actually handles a sense of smell called olfaction it sits in the cribriform plate neurons go through the cribriform plate synapse in there and send action potentials into our brain now if i follow it straight down it looks like it runs into these two bumps but it really doesn't it kind of curves and goes off into the brain these two spots right here would be connected to an eyeball which would be about here and here so these two stumps sticking out are called the optic nerve where the the right and left optic nerve meets is the optic chiasm that little spot is the infundibulum and the two little green dots are the mammillary bodies we've covered those before so olfactory nerve optic nerve cranial nerve number two cranial nerve number three is right here and that one is called the oculomotor nerve the optic nerve does a lot of vision the ocula and controls some pupil size the oculomotor nerve is going to do moving your eyeballs it moves the muscles or it controls the muscles that do eyeball movement so olfactory optic oculomotor okay now in order to see cranial nerve four on this model i actually have to take the model apart so i'm going to do that i'm just going to set the pieces aside because we don't really need them i'm going to get down to nothing but the brain stem and i'm going to put a piece of the frontal lobe back on so now we're just focusing on the cranial nerves olfactory optics oculomotor nerves those two little white stumps they're where the the midbrain and the pons meet now if i rotate all of this there's a little white line that starts just below the corporate quadrigemina and sticks out here it would come all the way off and run somewhere else that is cranial nerve number four that's called the trochlear nerve okay so olfactory it goes olfactory optic oculomotor and trochlear the next nerve is this little white stump that's on either side here of the pons and that is called the trigeminal nerve it has three branches tri and gemini for twins three twin branches so olfactory optic oculomotor trochlear trigeminal trochlear and trigeminal now the next three nerves are all on the base or the bottom edge of the of the pons right where the pawns and medulla meet and it looks like this white nerve is connected to this white piece right here it is not this nerve will go down and then go into the brain so this one right here is cranial nerve number six it's called the abducens nerve the abducens nerve moves your eyeball does abduction of the eye the next nerve right here there's two of them next to each other this one is cranial nerve number seven that's called the facial nerve so olfactory optic oculomotor trochlear trigeminal abducens and facial now cranial nerve number eight is this one right next to the facial nerve i'm sorry yeah called the vestibulocochlear nerve the vestibulocochlear nerve it goes to the vestibule of your ear and to the cochlea it's also called the auditory nerve or the acoustic nerve you can say this tubular cochlear nerve which is harder to spell auditory nerve or acoustic nerve they are all acceptable okay so that's abducens facial vestibulo cochlear now 9 10 and 11 you see this little um oddly colored part and this little ridge right here these two ridges right here are called the pyramids and then that little structure looks like a little piece of an olive that's called the olivery nucleus they're not on our list but between the pyramids and the olives are behind the olives the olive very nucleus there's actually three little nerves here it's hard to see but there's a nerve there there's a nerve there and then there's another long nerve here so this is cranial nerve number nine that's called the glossopharyngeal glossopharyngeal glossa means tongue and ferrex means the upper part of your throat it controls those so facial i'm sorry abducens facial vestibulocochlear glossopharyngeal okay this one is called the vagus nerve number 10 vagus not v-e-g-a-s like las vegas but vegas like v-a-g-u-s when you get into healthcare you'll learn about the vagal reflex or the vasovagal reflex causes people to faint and the vagus nerve controls your heart rate and your breathing to some degree so 6 7 8 9 10 and that's going to be 11. 9 is gloss ovarian gel 10 is vagus and 11 is called the spinal accessory nerve or the accessory nerve excuse me for one second i apologize in their grand wisdom when they designed our classrooms they gave us lights that automatically turn off to save electricity the problem is if i don't move enough they shut off on me so i'm not going to start this video over so six abducens seven facial eight vestibulo cochlear nine is glossopharyngeal 10 is vagus 11 is called the accessory nerve or spinal accessory and then right here on between olivery nucleus and the pyramids is cranial nerve number 12. that one's called the hypoglossal nerve it will come out through the hypoglossal canal goes underneath your tongue so olfactory optic oculomotor one two and three four and five trochlear trigeminal six seven eight abducens facial vestibulo cochlear nine ten eleven that's glossopharyngeal vagus accessory and then i have the hypoglossal number twelve okay now we could ask you on that model or we could ask you on the brain on the half shell the nice thing is on this model one half of the model they are actually numbered for you so that you can find them pretty easily now here i can see the pituitary so it's going to be difficult to see below it but this is the olfactory nerve these two stumps are the optic nerve and then if i can break it open i see the pituitary oh sorry i see the pituitary here the infundibulum this little mass right here that little white spot would be a mammillary body but this little stump right here it has the number 32 on it that would be cranial nerve number three okay that's your oculomotor nerve so olfactory optic oculomotor now on this model on one half let me show you this half olfactory optic the oculomotor is right down here but you see this little thin stem sticking out you can see why it breaks off very easily that's the trochlear nerve number four that's the trigeminal nerve number five there's six seven and eight abducens facial vestibulocochlear this is nine and ten kind of fused together nine is gloss ovarian chill the bottom half ten would be vagus that's the spinal accessory and that's the hypoglossal 1 2 3 4 5 6 7 8 9 10 11 12. learn the roman numerals learn the names of the nerves if i showed it to you on this side it does the same thing it's hard to see four and five but they're 6 7 8 9 10 11 and 12. one two three and four are hard to see there's five six seven eight nine ten eleven twelve i'm going to try to pick the model that shows that the nerve the best but you really have to learn where these 12 pairs of cranial nerves are i also drew them out and gave you an easy way to memorize them it's in one of the videos so thanks for watching i hope you had as much fun as i did oh by the way there's a couple of funny sayings to remember the nerves in order one is on old olympus towering tops a finn and german viewed some hops ooo which would be olfactory optic oculomotor on old olympus towering tops trochlear trigeminal now people can't memorize that one it doesn't relate to anything there's another one that says oh once one takes the anatomy final very good vacations are heavenly o once one olfactory optic oculomotor takes the trochlear trigeminal anatomy abducens final facial facial very vestibular cochlear good glossopharyngeal vacations vagus r accessory heavenly hypoglossal so i hope that's helpful again i hope you had as much fun as i did i hope you learned something do this to you can't stand it do it till you understand it do it till you can teach it to your classmates see you in the next video