what's up Ninja nerds in this video we're going to talk about the ear so to start it all off we got to look at the external ear so this right here is a part of the external ear it's actually called The Oracle or the Pina and it's actually made up of an elastic cartilage which allows for the ear to be able to be flexible and to be you know be able to stretch and recoil right so that's the that's the Oracle of the peenut it's a component of the external ear then if you actually look I'm stabbing this pointer out to the guy's like uh ear there's a little tube here a little tube that I can follow all the way down it's called the external acoustic or auditory meatus so it's a little Canal that allows for sound waves to pass through um another thing inside of this external acoustic or auditor meatus is little things called ceruminous glands which are modified aicr glands and what they do is they produce chemical called seramin and that substance helps to be able to deter insects or things from getting into the ear right if we follow the external auditory meatus we're going to hit a little barrier boom that little guy right there that connective tissue membrane structure that's actually called the tanic membrane so the tanic membrane is this little separating structure between what two cavities the external ear and this cavity over here which is called the middle ear cavity okay so we covered the external ear now let's go ahead and talk about the middle ear now so the middle ear again is actually I said we can actually call it uh remember the Panic membrane separates the external ear from the middle ear well here in the middle ear you'll notice this little tube you see this tube that drains all the way down here that little tube there that drains the middle ear into What's called the nasal cavity it actually drains it into What's called the nasal far um it's actually helpful for being able to equalize the pressure between the atmosphere and the middle ear so you'll notice that whenever you're flying at high altitudes you want to be able to your ears feels like they're plugged so when sometimes you open your mouth to be able to equalize that pressure right to try to pop your ears so that's what this little tube here is doing it's helping to equalize the pressure with the atmosphere in your middle cavity so it's really important if you look here you can see number 30 number 30 right there is a skeletal muscle structure it's actually called the tensor tempani so he's also a part of the middle ear what I'm going to do now is I'm going to pull this little tanic membrane out so that you guys can see it I want to talk about a couple little bones that are present in here called ticles all right guys so now if look here we got the tanic membrane so this is actually going to be the part of the tanic membrane that's actually next to or on the side of the external ear so this is the part of the tanic membrane that's on the side of the external ear now if I go ahead and flip it to the other side which is actually going to be pointing towards the middle ear part okay so this is now the view from the middle ear you're going to see again this is the connective tissue part here which is actually going to be a part of the tanic membrane but then I told you there's some really important bones that are actually on this called ticles These are the tiniest little bones in your body if you notice they're going to go in order of uh whenever the tpan tanic membrane compresses and decompresses these little ticles vibrate and they vibrate in order if you notice 25 is actually called malus okay so 25 is malus 26 is incus and then there's a little bone that actually comes off of this part like it's actually coming out at you there's a little bone that's actually attached to this little piece here at incus and that's called stapes and the stapes is the last part of the ticle that actually Taps on a little inner ear stru structure which is called the oval window okay so now that we looked at the tanic membrane we're going to put it back in there take another look inside the tanic um cavity or the middle ear cavity and then we're going to work to the inner ear all right guys so a little bit of orientation here you can actually see the tanic membrane right here and again I told you it's what separates the external ear from the middle ear if you look there's that little muscle that actually connects to that really important bone and this little muscle is called the stied is and the stiped is is actually connecting to this little bone right here little bone right there is actually called stapes it literally looks like a stirrup like when you have the saddle like you put your foot into the Little Stirrup there that's what the stapes looks like and whenever he vibrates he Taps on What's called the oval window um and actually helps to create fluid fill vibrations so again stapedius muscle right there stapes right here and then again this is the whole middle ear cavity here and then again you got like your ustan tube or your auditory your Fring oranic tube and again tanic membrane set separates the external ear from the middle ear all right so now what we're going to do guys we're going to go ahead and take a look at the inner ear all right guys so in order for us to be able to get a better look at the inner ear I need to take this little part of the bone off all right guys so now taking a look at the inner ear before we actually do that I wanted to show you guys you could actually see a part of the middle ear here so again 25 is malas 26 over there is incus and again those were the little ticles that were connected to the tanic membrane right all right so now looking here at the inner ear you see this whole bunch of structures here we're going to go through them piece by piece in kind of like an order so the first thing we're going to talk about is these semicircular canals so if you look here you'll kind of see all of them so like there's a half a circle there's a half a circle over here and there's a half a circle over there these are your semicircular canals and they're actually an outer bony Labyrinth which is made of peril lymph okay so again this is actually you know specifically you can say this is the anterior semicircular Canal this one over here is the lateral semicircular canal and then this one actually back here is the posterior semicircular canal and again they're the outer bony Labyrinth which is made of per lymph now inside of the semicircular canals you have these little things called Ducks so you see these little blue structures here inside of the semicircular canals these are actually called your semicircular Ducks and the semicircular ducks are actually going to be an intermembranous Labyrinth filled with what's called endolymph okay so again semicircular canoun is the outer white part but this inner blue part here is the in it's called the semicircular Ducks made of endolymph at the end part here you can actually see a dilated region of the semicircular duct right here this right there is actually called the ampula of the semicircular Ducks the ampula of the semicircular ducts has a specialized structure found in it called the christe ampuis and the christe ulis is actually helpful for being able to detect what's called dynamic equilibrium okay so again that's that and enough shell semicircular canals anterior lateral posterior and they're the outer bony Labyrinth which is made of peril lymph inside of them is an intermembranous Labyrinth made of endolymph and that's called the semicircular ducks and right there this dilated region right there is called the ampula of the semicircular duct and it consists of the chiste ampuis which detects dynamic equilibrium all right guys so now we're going to take a look at another component of the inner ear and it's actually called the vestibule you can actually see it it's right there number 31 and it's that little thick white part there it actually kind of looks like the it's the base structure from which the semicircular canals are coming off of okay so again 31 is the vestibule and the vestibule is actually going to be the outer bony Labyrinth which is made of peril lymph now inside of the vestibule you have these two little like uh fluid filled parts right here so you see this right there 43 is called the utricle and then 42 down here below it is called the SACU now again one more time the vestibules the outer bony Labyrinth which is filled with Peril lymph inside of it is these inner membranous labyrinths which are filled with endolymph and again what are those structures called first one is 43 which is the urical below it 42 is the sacul that makes up the actual vestib in the inner structures another thing guys and we'll talk about in the actual vestibular physiology but inside of this actual utricle and sacle you have a specialized detector called the macula uh interesting uh Point here inside the immaculate you have these little things called oolith crystals and they're actually made like calcium carbonate crystals and sometimes in people who have what's called benign proxis positional vertigo those calcium carbonate crystals can actually get dislodged and get stuck inside of these little semicircular ducts here and can throw off the person's equilibrium and balance and produce what's called vertigo so sometimes they have to do what's called a calth repositioning procedure or you know give them antivert as a medication to treat it okay so again just a little clinical correlation so again utricle sacul have a structure inside of them called the macula and he's helping to be able to maintain what's called Static equilibrium all right guys so all I'm doing here is I'm just kind of positioning the inner ear so it's easier for you guys to be able to see all the anatomical structures all right so the first thing that I want to talk about is these two little Windows here so you see 32 that's actually called the oval window now the oval window is important because that's what the stapes Taps on remember I told you guys that that the the stapes is tapping on the oval window and creating these fluid fil vibrations okay so he's really important for whenever the stapes Taps on him he creates these fluid fill vibrations within the CA and we'll talk about that and then over here this little guy over there is actually called the round window the round window is important because whenever these fluid fill vibrations are occurring you want to prevent the actual vibrations from being scattered out into the inner air and being lost so the round window helps to be able to prevent the scattering of those actual uh vibrational impulses okay so he an important structure for that next thing we're going to do now is we're going to take a look at the CIA and the three chambers all right guys so now what we're going to do is we're going to take a look at all three chambers of the ca so the upper chamber is this top chamber right there is actually called the scale of vestibuli it's an outer bony Labyrinth which is filled with per lymph again okay then there's a Middle Chamber I'll show you guys here in a second it's actually called the clear duct or the Scala media it's the inner membranous Labyrinth which is filled with endolymph okay and then there's a lower chamber called the SK Scala tempani and the Scala tempani is actually going to be another it's the lower chamber and it's the outer bony Labyrinth which is filled with pery so real quick recap before I show you guys again scale of auli is outer bony Labyrinth with per lymph this the Scala Media or the ccar duct is an inner membranous Labyrinth filled with Indo lymph and then the lower chamber is the skeleton panai which is the outer bony Labyrinth filled with Peril lymph so now let's take a look at these structures so the first one I'm going to take a look at is the scale of auli let me take this little piece here off so that you guys can see inside of it what it looks like okay so again this is going to be the little inner chamber here called the Scala vestibuli okay and it's made of Perry lymph now let's get that out of the way and I'm going to show you guys another structure here so if you look here you can see number 50 50 kind of is like it looks like this all this like uh white and red structure here kind of going all the way around so I'm going to follow it up like a little Loop here loopy loopy loop right so 50 all that right there is called the clear duct and again that's going to be the inner membranous Labyrinth which is filled with endolymph inside of this structure on What's called the bacillar membrane you have a special detector called the spiral organ of Cy and it helps to be able to pick up sound waves and those sound waves will then be sent okay to our primary uh auditory cortex which help us to be able to perceive those sounds in different ways Okay so so again clear duct the special detector is the spiral organ of Cy picks up sound waves now the lower chamber is a little tough to see it's actually 40 here it's actually that's what we're trying to denote it as but it's underneath the CER duct so if you could imagine this chamber a lower chamber underneath this actual clear duct that would be the Scala tempani okay and again that's actually going to be an outer bony Labyrinth which is filled with Peril lymph okay now that we've covered all the chambers we're going to put the inner ear back together and in place so that we can take a look at the vestibular cocar nerve all right so if you guys look here we're going to have the vestibular cocar nerve which is again cranial nerve 8 so if you look here it's this whole whole chunk here this whole chunk here if you can look 45 is trying to represent it as from this chunk here all the way down to this whole chunk here okay so that's the vestibular clear nerve or cranial nerve 8 and it actually runs through this little little divot here that you see called the internal AC tic or auditory meatus so again there's two branches of the vestibular cocar nerve this whole Branch right here which is actually coming from the CIA so it's called the clear branch of the vestibular clear nerve then there's another branch which is actually one's coming from over here and then this whole part over here that whole Branch there coming this way is the vestibular branch of the vestibular clear Nerf okay that's taking up information from the semicircular uh Ducks specifically the ampula and it's also taking this information from the immacula inside the utricle and the sacul and you can actually see they actually run through a Gangland this little pink little Gummy structure right there it's actually called the vestibular gangon uh sometimes they even call it Scarpa ganglion so again vestibular gangon there and then there another pink gummy structure right there called the vestibular ganglion or again you can call it Scarpas gangon okay guys so now to wrap it all off we're going to do a quick recap of falling sound waves all the way through the ear and then how that actually gets carried on the vestibular cogar nerve all right ninja ner so let's go ahead and finish this all up so if we follow sound waves all the way from the actual atmosphere so let's say there're sound waves so someone's like me talking to you guys what happens is those sound waves are traveling in through the external acoustic or auditory meatus then as those sound waves travel through the external acoustic or auditory meatus they actually hit the tanic membrane and when they hit the tanic membrane the tanic membrane actually undergos what's called compression first and then it actually decompresses after it compresses and decompresses it has a little vibration of those little bony oses remember those so the first one that it'll vibrate is actually called malus the second one that will vibrate as a result is incus and then incus will actually cause the vibration of stapes and then stapes will tap on that oval window if you guys remember now whenever the oval window is tapped on it creates fluid filled vibrations and what happens is the vibrations actually move through what's actually called the scale of vestibuli that upper chamber and then it moves downwards and bends the basill membrane and the basill membrane is a membrane that separates the clear duct if you guys remember that from What's called the scalan which was the chamber underneath when it bends the basill membrane or changes that causes uh fluid F vibrations within that clear duct what happens is it stimulates little hair cells that stimulate What's called the spiral organ of Cy when it stimulates the spiral organ of Cy those hair cells when they're stimulated it sends Action potentials down that clear branch of the vestibular clear nerve and then what happens is that'll take that information to eventually the primary auditory cortex in the temporal lobe and that helps us to be able to allow for understanding or perceiving those different types of sound waves right all right Engineers so in this video we covered a lot about the ear I really hope it made sense I hope you guys enjoy wa it until next time