and engineers in this video we're going to talk about the structure of the inner ear alright so what we're going to take a look at just so that before because what we're going to do is we're going to have an individual video on different sections of the inner ear so what we're going to do is we're going to talk about the anatomy of the inner ear and then again we're going to separate each component into individual videos we'll talk about them in great detail so it's go ahead and get some Anatomy down alright so first off what is this big old structure right here called this big old like snail-like looking structure this big old beast right here is called the cochlea okay so this big old structure right here that's nice and windy and twhirl swirly and stuff like that that's called the cochlea now the cochlea is actually broken up into three different chambers that will look into great detail okay so there's three different chambers of it okay one of the chambers is called the skaila vestibuli okay the one in the middle so this is going to be the upper chamber okay so this is the upper chamber in the middle is going to be what's called the skaila media and the scale of media is really important because this is actually going to be a nice little endo lymph like structure okay you're going to also call the scale of media the cochlear duct so another name for the scale of media is called the cochlear duct this is the middle layer okay this is the middle layer then the lower layer the bottom most layer of the cochlea is what's called the scaler tenpin I okay the scale is anpan I and this is the lower chamber what's really important about this is that on the scale of vestibuli you're going to have a really important structure that we talked about within the middle ear we said it was called the oval window it's called oval window remember the state bees the stay bees is tapping on the oval window and when it's tapping on the oval window because of sound waves right the sound waves were actually creating vibrations that were compressing and decompressing the to panic membrane that was moving malleus incus stapes and scape pieces tapping on this old window we're really when it's tapping in the window is tapping on the scale of the skidline why is this important because the scale of the stimuli is filled with a specific type of chemical okay a specific type of fluid which we call perilymph okay it's called perilymph okay which is more of a harder like fluid substance the other one there was a structure that was right inferior to the oval window remember that one was called the round window what was it called it was called the round window and if you remember we said that the round window was important because if you remember some of the sound waves are going to come through the different parts of the scale of the stabiliser scale of medium scales and panel when averaged is some of those sound waves will actually can get lost or scattered throughout the inner ear we don't want that because I can interrupt the actual action potentials going to the brain so what we want to do is we want the round window to prevent the actual scattering of those sound waves we remember with the actual scattering those sound waves into the different parts of the inner ear okay so again the round window is really important and that's actually located within the skaila compan eye and again we'll look at this in a more deeper view when we get to this individual cochlea and we'll talk about the spiral organ of Corti and a whole bunch of other stuff okay but another important thing is the skeleton Panaya is made of what's called perilymph which is more of like a harder fluid like substance with a little bit of calcium and stuff in it okay then a scale of media which is really really important the scale of media are the cochlear duct which is the middle layer is rich with a fluid called endolymph and we're going to talk about in two limbs a lot we're going to talk about what kind of structures are making it into lift what I want you to remember about the end of list is that it is a potassium rich fluid it is a potassium rich fluid located within the skaila media are the cochlear duct so what you're able to notice here is that the scale of media which is filled with in the lymph is surrounded above it it has a scaler vestibuli which is filled with perilymph below it as the skeleton panel which is filled with perilymph perilymph is what's called the outer bony labyrinth okay so if something is made of perilymph it's a part of what's called the outer bony labyrinth so again this one's made of perilymph also so this would be made of this is actually called the outer bony labyrinth and then the structure that's actually made up of endo lymph the structures that consisted in the lymph is actually going to be consistent to be called the inter membranous labyrinth so it's called the inner membrane as' labyrinth so the outer bony labyrinth which is the scale of astable on the skeleton pan i consists inside of it with an inter membranous labyrinth which is made up of in the lift okay all right sweet deal so that covers that part of the cochlea we'll talk about a little bit more detail but if you see right here you see sort of ending point here you can see that the cochlear duct is this nice little blue structure here so we can definitely clearly see here this part there which is called the cochlear duct okay and then we're going to have again two different components we're going to have what's called the oval window and then we're going to have what's called the round window and remember we can have two chambers now this isn't a perfectly formed here but we're going to say that this part up here let's say above the cochlear duct this is going to be what's called the skaila one vestibuli below this is going to be this gala timp an eye and in between is going to be the cochlear duct okay and again if you remember we could say here would be the oval window which will be where the state piece is tapping on and below could actually be the round window and the round window is where the actual preventing of the scout sound waves from being scattered so we deal and if you want to know one more thing this point here at the end which is all the cochlear duct kind of makes this nice little spiral here and it comes to this end point here you see this end point here right there I'm gonna write it here this point here where the actual skaila vestibuli so again what would this one be skaila vestibule is kayla can pan i you see that part where the scale of the stip line of skeleton pan i actually come together and there perilymph combines that's an important structure there and that structure is actually called the helical crema okay so it's where the scaler vestibuli and temp and i perilymph mixes all rights we do that's the helical crema now another thing i will talk about in great details you see this like due to brown kind of like structure here the dude brown like kind of structure is actually called the cochlear branch of the vestibulocochlear nerve okay so if you see this part right here this part right here imagine there's actually nerve fibers coming through here and then actually come through a ganglion which is called the spiral ganglion we'll talk about this in detail but these axons actually going to be a very very important component of the vestibulocochlear nerve so if you see these fibers that are coming out here it's actually going to be important component of the vestibular cochlear nerve okay but this branch here which is coming from the cochlea is what branch it's the cochlear branch of the vestibular cochlear nerve so what branch is it it's the cochlear branch of cranial nerve 8 okay and cranial nerve 8 is going to be called the vestibular cochlear nerve okay so we deal so that covers that part that covers the cochlea now we're gonna talk about the next one which is going to be the vestibule so what is this next part here the vestibule is really important because the vestibule is a pretty decently sized structure here let's actually write it right here this part here is the vestibule okay it's a very kind of like vestibule is kind of like the body okay so this big whole part here I'm gonna kind of like encircle here like this okay you kind of see I'm kind of in circling around it here all of this part here is actually going to be the vestibule okay all that part that I moved around with the purple that's all the best to Buell what's important about the vestibule the vestibule is actually can consist of two important structures it's going to consist of what's called the utricle okay internally so the into vestibules going to consist of a structure called the utricle and it's going to consist of another structure called the saccule okay and again we'll look at these in more detail just let me get you guys introduced to them but what's important to remember is the vestibule is the outer bony part so it's called the outer bony labyrinth so the vestibule which is this whole big structure here it is an outer bony labyrinth so what does that mean that means it's filled with perilymph okay it's filled with perilymph so therefore since as Phillip Perry limpet is the outer bony labyrinth and again inside of the vestibule which is the outer bony labyrinth it consists of the utricle and the utricle is filled with endo lymph okay so this is filled with in the lymph which is potassium rich okay this is potassium rich and this is going to be a d what inner membranous labyrinth okay sweet deal same thing with the sake of the saccule is a little bit smaller see the utricle is actually going to be if you want to see where it's placed here I'll show you where it's placed so let's say that this one right here I'm going to point on with red I'm going to bring him down here that one right there is the utricle okay so this upper one so if you come here for the best ability that this is the inferior portion that's the superior portion the superior portion here is going to be the utricle the inferior portion here is going to be the kyoool so what is this structure here called this one here this is the saccule okay so they have the saccule which is the inferior part and then over here we're going to have the utricle and again the saccule what's important about the saccule he's going to consist of in the lymph which is a potassium rich fluid and he's going to be a part of the inner membrane Asst labyrinth okay now why am i mentioning all this stuff and the reason why is because the saccule and utricle just like the cochlear duct and this endolymph is important because these structures will talk about in way more detail when we get there but they consist of things called hair cells okay they consist of things called hair cells okay and these hair cells are really important because the utricle and the saccule are a part of a larger structure okay so really when we say vestibule vestibule is the outer bony labyrinth and if we really really wanted to be super super picky the vestibule actually consists of this structure here now let's actually come to Magnus it actually consists of a structure called the utricle and saccule but inside of the utricle and the saccule they have a special structure called the macula so they have a special structure here called the macula and we'll talk about this in great detail because the macula is important for static equilibrium which is like whenever you are linearly accelerating so if I'm actually going and I'm in a car and I hit the gas room I'm go ahead moves back or when I hit the brake my head moves forward so when I literally accelerate and I decelerate or when I tilt my head to the side so if I tilt my head to the right side I can activate these guys if I tell them to the left side I can activate these guys or let's say that I'm falling I'm in an elevator and some terrible thing happens and the freakin cord breaks and I'm flying not ah you know I'm flying down that can also activate that so a vertical deceleration could also activate these structures okay it's a sweet deal so again the vestibule is the outer bony labyrinth Philip perilymph consists utricle and saccule which are filled with into live these are the inter membranous labyrinth they can contain a special structure which are consisting of these hair cells but these hair cells as well with other structures here you'll see them later they're called an otolithic membrane with Auto Konya okay little creek calcium carbonate crystals they make up what's called the macula which is a special detector for what type of equilibrium we said this is for static equilibrium okay like I said we'll go into this in more detail when we get there and then since we covered this part over here the scale of media are the cochlear duct it has a special detector so it has special hair cells covered with us called a tectorial membrane and these hair cells with the tectorial membrane make up another really important structure called the spiral organ of Corti okay and this is interesting for sound okay so whenever you actually I'm talking to you guys right now the sound wave that you guys are hearing is carried out by the spiral organ of Corti okay so auditory information is going to be picked up by the Spiro organ of Corti alright so we did we did that next thing you see these suckers here these canals these canals we have three of them okay we have three canals this one right here is called the anterior semicircular canal oh it's really you there for some reason circular canal this one in the back so it's coming here and it's moving posterior lis this one here is called the posterior semicircular canal and then you have one imagine it coming out at me like it's punching me in the face okay so imagine this bad boy is coming at me to punch me in the face this is coming out laterally okay because remember this is an internal structure so when this is poking out remember we said that this is actually a little depression within the middle ear cavity or the Topanga cavity the medial wall so this guy is trying to come out words they're trying to go outwards towards the ear so this is actually going to be lateral semicircular canal okay so now that we got that the semicircular canals what's important about these guys the semicircular canals are going to be the outer bony labyrinth so outside of this again imagine kind of like I'm kind of highlighting it right here you see all this stuff that I'm trying to like move in with like little lines that part there is the outer bony labyrinth which is made up of hairy lymph okay now why am I telling you that so the outer bony labyrinth here which is made up of perilymph so it's consisting of perilymph so this is the outer bony labyrinth inside of it there's this nice little blue structure there what is that blue structure they're called the blue structure inside of this is called the semicircular ducts semi circular ducts another important thing is this semicircular ducts so this is a whole semi circular duct here this is the semicircular coming back and this is the semicircular duct going this way all right but these semicircular ducts dump into a nice dilated region which I'm going to have a highlight here in pink I'm saying that this one right here kind of dilates right here this kind of dilates this kind of dilates and that kind of dilates those little dilations at the end part of the semicircular canal tears it's reading getting ready to go into the vestibule area these little dilated regions are called the ampulla of the semicircular canals so what is this part right here called what do we say this was this little dilated regions here any tile ated regions here called the ampulla of semi circular canals all right so it's the ampulla so that dilated region there it's consisting of a very very special structure so at the ampulla the semicircular canals that dilated region right there there's semicircular duct right there that so the semicircular ducts are moving all the way around but they have a little dilated regions right there that dilated region which is in the ampulla is a very very special detector that special detector which is in the ampulla it consists of these hair cells that are covered with like a collagen Asst gelatinous membrane called the cupula okay and that basically makes up a very very special detector called the cristae and Valeris and the crista ambulators is important for what's called dynamic equilibrium okay what do I mean if I decide to turn my head to the right turn my head to the left or I decide to do circles this guy is really important because he's helping to maintain my balance my posture my equilibrium whenever I'm doing head rotations or angular acceleration so he is good for Krista Bueller is important for angular acceleration where is the macula which is consisting of the utricle and the saccule that's important for static equilibrium or linear acceleration okay whether it be horizontal or vertical and then the last one which was the cochlea which is consisting of the cochlear duct these hair cells are important because the spiral organ according is detecting sound waves vibrations in the air okay and turning that into electrical potentials for us to perceive okay so in this video we covered that now one other part here let's do this one and this color here you see this part here this is actually another branch of vestibular cochlea of crane and r8 but this branch is coming from the vestibule and it's coming from me what it's coming from the actual semicircular canals but I guess maybe they don't have much love for the semicircular canals but they are coming off the best of you but they call this branch that's moving with the vestibular cochlear nerve they call it the vestibular branch of the vestibular cochlear nerve so what is this branch here called holy crap get rid of that one this is called the vestibular branch vestibular branch of cranial nerve eight or the vestibular cochlear nerve and just like I said this had spiral ganglion okay these also have a gang run along the way it's actually part of it's called Scarpas ganglion okay so these are the sudha pseudo unipolar cell bodies which have the peripheral process coming out here to the vestibule in the semi surgeon canals and their central process is going into the central nervous system same thing here spiral ganglion have their peripheral processes coming out to the cochlear duct and they have their central process going into the central nervous system alright and they'll take these informations into the cochlear nuclei and we'll have that Pat well I'll talk about that in the actual auditory pathway okay whereas the vestibular branch will take it to other structures called the vestibular nuclei and again we'll have another video on that arson engineers we covered basically the anatomy of the inner ear what we're going to do is we're actually going to have individual videos where we're going to focus on the vestibule and it's the structures inside we're gonna have another video on the semicircular canals and the structures that are inside those special detectors and then we're gonna have another video on the cochlea and the structures that are inside and we're going to talk about how static equilibrium is being affected how dynamic equilibrium is going to be affected and how sound waves are sound is actually going to be effective so if you guys need any extra help with a little bit more of the actual ear anatomy we're going to have another video that you guys can click out on the corner of the video it's going to be talking goin over the external ear the middle ear and the inner ear and actually taking a model an Anatomy model and you guys can see them a little bit more depth if you guys need a little bit more help with that all right but ninjaroos other than that I hope this made sense I really do hope that you guys enjoyed it you guys did please hit the like button comment on the comment section and please subscribe as always engineers until next time