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as well. Um, there's a problem with the event on Facebook. I have no idea what happened, but it's like not there anymore. So towards the end, up with the middle link, um, in the tract, Um, and you'll consign up for that lecture is happening tomorrow. It's gonna be on the cerebellum. Um, and yeah, I think I'll just past understand. And you saw everybody. My name science. They'll be talking to you about the anatomy of the brain stem. Hopefully, you can see my screen. You can see my screen, right? Yep, yep. So the as it's offset brain stem was quite daunting when we did it back in the day, but I try to make it as easy as I can. So just to go back on what it started mentioned tomorrow we will have another lecture on the cerebellum. Same time. Um so, yeah. So what I what I would be coming today include the embryology off the brain, stem the brain stem in general, the features of them, and then we'll have to quizzes. So the immunology of the brain stem, as we all know, from your first cases in some three at four weeks of gestation. You have the neural tube, it comfortable notochord and give you three outpouchings the President Cephalon. The medicines are flowing the rhombencephalon on and then at eight weeks of gestation, you'll have the division off. These three hours apart brings the presence. Avalon becomes a talent stuff long that diencephalon which become your Sarah Sarah Bella hemispheres and your D brain structures. And then you have the wrong been stuff along the divides into your medicines Cephalon and my islands, as long your metenkefalin becomes your palms and your arms like Roshal aspect of the fourth ventricle and the new myelins that long becomes your medulla on your card aspect of the fourth ventricle, your medicines have long does not divide any further and just give rise to your midbrain and your cerebral aqueduct, which are continuous with your dimes. Cephalon. So what is the brain stem? Give this image of the rights that's the brain stem. These direct circles you can divide the brain stem for is entirely or vertically. The most common answer is the horizontal division that the brain stem, which from superior to inferior or from Rostral Kado, is the midbrain pons and then you medulla. The medulla ends at your for a man Magnum, which is the slanted line here. Anything distinct before Even Magnum is your spinal four on. As I said before the mid brain off the medicine Cephalon discontinuous with a dye encephalomalacia, hypothalamus elements and every follow mr here. And then you're metalized intonation sparkle. The brain stem is very important, has very important and atomical relations. And to close your left, right, I've only talked to you about the superior in fear limits. And as you can see this image anterior to the brain stem. You've got this big red artery that's of basilar artery, which is your main contribution for your posterior circulation of the brain and then antibiotic that you've got declined us, which is part of the basilar part of the occiput. And then, which is why, as you can see in this image, creed demonstrates, you can have a lot of your surgical approaches that come from the front to do tackle malformation of the brain on As you can see, posteriorly, you've got the cerebellum and the fourth here and here. That's mainly at the level of the ponds and then behind. Now you've got your squamous part of the oxy internally on this section is actually really nice depiction. You see these white matter tracks, and that's very, very important. Your brain stem contains basically all of your White Matter tracks that go up and down connecting your spinal cord to your brain. It also contains are cranial nerve nuclei, which my colleague touched upon in her previous lecture of cranial nerves. On very importantly, I'll mention this towards the end for the particular formation, which is essential in consciousness on can be affected in what we know what's known as locked in syndrome or pseudo coma. So that was the horizontal division of the brain stem. They've also got a vertical division of the brain stem. As you can see here, you've got from anterior to posterior you call your basis, you've got your take mental and pink, and the needle you're a tech seven purple on. The reason it's important is because the tectum and the tech tech mentum arise from your primitive mural corner. The basis off your brain stem is, um, biologically later on in the timeline on the nephews together to form the brain stem. If you look from a top down the spect it and gives you a better idea of what the demarcation and the boundaries are. Four said vertical division of the brain stem. So over here you've got the cerebral aqueduct which connects you're still adventitial to your fourth ventricle on anything posterior to that is called detect. Um Ondas. You can see this is your cerebral acted up behind that That's your tectum. Anything anterior to your cerebral aqueduct is your tegmentum. So you're take meant. It is mostly where you have all your nuclei and almost of your white matter tracks running in the tegmentum and then the basis. As you can see, this image is anything an interior to the substantia nigra on your car, and it also includes your cross three. Brian, which contains your cortical final track to corticobulbar, tracks new cortical pointing tracks and so that those are your three divisions your basis you take men's haven't detected on down, obviously, like in your like ventricles lecture. You like you were talked about the cisterns. It's good to know it, but you want to ask about the many Oscars would be very unfair for them, but the most important one you need to know is the interviewed uncle of sister. The reason it's important is because of very important cranial love. Traverse is through the interpret on killer system. I think that the level of the mid brain so the most important thing that they'll ask you are in your office. Keys are number one criminal nuclei off the bread stuff on identifying cranial nerves on Catterick samples. And so I'll talk to you about more of those things. So cranial love architecture from the crania loves lecture. You know, you travel can lives on. They are supplied by the cortical bulb our tracks on So and any descending pathway has only got two orders. Um, you're on and on Upper motor neuron and a little more to Iran. The cranial nerve nuclei is the synaptic connection between those two, so the upper motor neuron comes from the cerebral cortex goes into the brain stem in absence of the cranial nerve nuclei. And then that's when you have your lawn. Martin, you're on command of the brain, and it's very important on very high yield. To know the architecture off how each of these nuclear are placed in the brain stem because once you know this, it becomes easier to localize pathology as well as localizing where the crane loves our exit, the brain stem. So, um, this this is the method of that worked for me in terms of a mental organization. You've got your cranial of nuclei from medial collateral on. This is an order. So the most medial are your PSA matter mortar nuclear. So matter multinucleate is in the name. It's all about cranial nerves that have mortar connections. And there's four Samassa more two nuclei and this image, really my shows. Well, in terms of color, you've got your ocular mortar nucleus or your third nerve nucleus. Then you've got your trochlea nuclear. So you're 14 of nutrients and they're bored located in the mid brain. Then you've got your sixth number, your abductions nucleus, which is at the level of the ponds. And then you finally got on this one, which is your height, velocity pas or your 12th Now, please. Which is in the midbrain? Medulla. So that's it. So much more to nucleus. Obviously, these are not the only cranial nerves that supply muscles, But these are the four most immediate criminal of nuclear, then just lateral two that are in the color yellow. You've got your viscera, mortar, nuclear, your viscera most nuclear Very important because they are the start off the preganglionic Paris sympathetic nerves. Very important, because in the central nervous system, all our a sympathetic nerves have their own respective ganglion where they go and synapse and then from the ganglion, you got your postganglionic person besides fibers, it's very high. Yields know from the cradle. Um, you cry, I you've got preganglionic parasympathetic nerves that come off on the most important ones are your CW nucleus or you're reading the Restoril preganglionic nucleus and the level of the mid brain. As you can see, it's just beside your ocular, more nutritious on. That's important because it's helped. It helps in your ciliary muscle movement. Then, if you go more distant at the level off the fourth ventricle, as you can see here, you've got your salivatory nuclear, a superior salivatory nucleus on an inferior celebratory nuclear's. Your superior salivatory nucleus supply is supplies your facial nerve while you're inferior. Salivatory nucleus supplies your ninth nerve or your PSA fine job. And so the superior salivatory nucleus goes to two ganglion. It goes to your summer and develop ganglion annual terrible Palatine ganglion. And they supply the nasal mucosa of the fine Jill before PSA as well as a sub mandible and the sublingual glands, as well as the lacrimal glands that helped in like tear production. Your inferior salivatory nucleus goes through the parotid gland and that provides that to, as I said, your 9th 20 a nerve and that provides ganglionic parasympathetic, um, stimulation to the brought it on the Lastly, you call your daughter bagel more to nucleus. This is the easiest to remember because the vagus goes to your heart on your abdomen and provides parasympathetic innovation of those past body, then on third lateral to that lateral to the restroom or nuclear, you've got your bronchial mortar nucleus. The bronchial is a synonymous term for that. Your pharyngeal arches its very high yield. To know your Fanjul archers want to 65 in believes as you age and it goes in order. So your first one is your fifth nerve or your trigeminal of the second Fanjul arch is your seventh nerve or your facial. Your third Fanjul arches your ninth nerve for your loss of fine Jill and your 4th and 6th annual arches are your tent in Vegas. And so you've got four brand kills, most nuclei, and this is where the rule of four applies. Because everything is in fours. You've got your mortar nuclear sub trigeminal nerve, which goes to your muscles and mastication your media natural pterygoid your masses. There, on your temporal is the need for your facial mortar nucleus. Your facial motiveless goes to your muscles of facial expression. Then you've got the nucleus and biggest at in the medulla. That's important because your ninth nerve in your 10th nerve as well as some of your accessory nerve their nuclear. Is it the nucleus ambiguous, ongoing supply their own muscles. So you're pharyngeal on your line gel muscles as well as your sternocleidals mastoid and your traps on. Then, lastly lateral that we've got your viscera sensory and Special center in UTI that's represented by the blue on the right of the image. The most high yield to know is your trigeminal nucleus. It's the longest one standing the entire length of the brain stem, and then from superior to inferior your body amazing cephalic nucleus, your principal century nuclear's on your spinal nucleus. It's very high. You know what each of them do. Your spinal uti is is pain in temperature. Your principal century is like touch and your medicine cephalic. It's probably reception. So those are the sensory information that comes in, Which is why, in this images you can see it's the Afrin nuclear. So you have incoming arriving information that then goes up to the ventral posterior medial nucleus off your thalamus, and then you want it like, quite clearly, see it here. But just at the level of your cerebellum peed uncles, you've got your vestibular and Kocaeli. You don't have to know each of the divisions of them. You just know that it's, uh, the level of the cerebellum peed uncles, and it helps in your auditory and balance sensations. Lastly, you've got your nucleus off tractor solitary ISS. That's very hard. This is very important nucleus because it takes the Afrin's off three notes. It takes the Afrin's of your seventh nerve, your ninth nerve in your 10,000. We have facial glass if I injured and your vagus so as you know, the anterior two thirds of your tongue. Taste comes from your facial nerve and the posterior. One third of your tongue comes from your 90 day supply, and they all arrived at the nucleus. Tractor. Solitary is on, then. Obviously, you've got your cardio cardio respiratory centers and all your viscera sensory information for your vagus. Any loss of angle coming into the nucleus. Tractor solitary A. Such as your carotid bodies and your aortic Sinuses. So all your chemo receptors and the counter receptors come into the nucleus of track. The solitary is It's also sometimes fall, the solitary nuclear's. But the old synonymous so very high you need to know your cranial. Um, nuclear. Um, this is stumped a lot of people, and it's often asked me ask you All right, so I will not talk to you about the external features of the brain stem. They often will just ask you to point at something on the brain stem, and you're gonna have to be okay. Identify the pyramid. It's You're gonna have to know what's Anterior. What's positive with the pyramid are so there's very high, you know. So for the brain stem you got to use, you've got anti review and your posture. You any anti review? As you can see, this is your temporal lobe. This is looking up. This is your pons. This is your med dollar on, then. This right here is your midbrain. Your midbrain has these two pillars. They are your cerebral peed uncles. Basically the take your internal capsule and all your pathways, and they go down on. So there's just a like a white matter bundle, you cerebral peed uncle's, as you can see on your body upon is the reason you have this out. Pouching on your pons is because off your pointing fibers that move for is on Tilly into the cerebellum. And then you've got your dollar here, Um, this medulla you've got the central line of demarcation that's called your anterior median fissure or the ventral median. Fisher. They are both synonymous and just lateral to that. The what I'm pointing to right here. Those are your pyramids off the medulla and just lateral with the pyramids. You got your olive a really clear or your inferior olives or just the olives. Onda. So that's how it's structured from medial natural. This line between the pyramids and the olives is called the anterior lateral soldiers, and then the line our. Then there's a fissure, just lateral to the olives right here. That's your posterior lateral soldiers. The reason I'm giving emphasis on that is because they are very high, you know, because a lot of cranial nerve nuclei exit from those two. Solid. Um, I'll go into the exact location of the cranium you climb in the next side, but that's basically all you have to know in terms of the interior view off the brain stem. So you've got your pyramids, olives high yield. You got your ponds. This where they meet. It's called the Pontomedullary Junction, and this arm groove in the center is your for a man cecum. That's your midbrain anti. Really. You can see your PSA people peed uncles. Um, and as I said before, between the peduncle, do you got your interpret dunk? Ular fossa? Your interpret, um, killer sister on the the junction between the midbrain and the ponds is called upon toe medicine. Cephalic Junction on. It's clear why that's the name, but that's the most important thing. Um, lastly, as you can see here, it's marked as the pyramidal biggest devastation. It's at the distal end off your medulla. A lot of text books are often confused. Us. So what is the inferior limit of the medulla? Some say four AM and Magnum. Some stayed. Accusation. The pyramids. Ideally, you'd like it to be at the same level, but the Doctor station of Pyramid is is as the old lawyer corticospinal track. So you're pyramidal. Tract must check a state, which is why you have contralateral symptoms when you have a lesion there. So that's the interview quite self explanatory, because you can see that outpouching up the ponds now moving on to the posterior view. Um, it's not as easy as the front because you've got a lot of structures of the back. But if you can see these two main pillars through your cerebral peed uncles, they descend from internal capsule or they go down. That's your third ventricle. This opening this major rhomboid shape is your fourth ventricle, and so you can imagine the cerebral back productive just in the midline. Um, you've got the you've got your pineal gland here, which sits in, or Burstein's, a triangle and the posterior aspect off the off the mid brain that how you identified the mid brain from a posterior view is by looking at These four are part things the other day on the top. True, I your superior Caligula on the bottom, too, or you're inferior colliculus throat and singular, your inferior colliculus. Very important to know what where they are and what they do. So your superior colliculus is involved in York Psychiatric. I'm movements. You're gay centers, and so you have a lesion there. Your eye movements are affected and it's connected. And you've got Brant like the track that goes from the superior colliculus to the lateral geniculate nucleus of your thalamus is called the Break in Superior colliculus. Similarly, the inferior colliculus also goes to your thalamus with that ghost. You, me, a medial geniculate nuclear syphilis on it's connected by the brachium inferior colliculus, and it's responsible for your order trees stimulus. So whenever you have on like whenever you hear a noise less than airplane flying and then you can immediately look at where it is in the sky, that's your superior. In very critical. I, working together three eye movements and to like, understand where the noise is coming from just inferior to your inferior colliculus at the roof. I'm just above the roof of the fourth. You've got this nerve here. It's very, very high yield for you to know that off the 12 cranial love, the only nerve that exits the posterior aspect of the brain stem is your fourth enough or your truck. As you can see this image, it comes out. Posteriorly wraps around the mid brain and the ponds and then exist from a Z concede it's here now and comes up interior. So that's your fourth enough only now that exits from the posterior aspect of the brain stem. There, this is your fourth ventricle. As I said, it's rhomboid and shape. The bottom is your floor of the fourth and then just natural to it. You've got your cerebellar peduncle. Your cell ability to uncles are very, very high. Yields bill to the point of attachment of your cerebellum to the brain stem, and you've got three cerebella tonsils. I won't touch much into it because that's tomorrow's lecture, but only need to know is you've got your superior Salovaara peduncle Here. You've got your middle cerebellar peduncle here, and it's not marked this image, but just here, media immediately here you got your inferior cerebellar peduncle. You've got three cerebellum. Did uncles add on the lateral aspect of the fourth on the superior aspect? You've got your superior vena because obviously there this horizontal band off white Massa, as you can see in marked here it's called us. Try um a generous this trial medullaris basically divides your fourth ventricle into an upper part of the lower part. So if you see them on a cataract dissection, it's very helpful to know that anything below it or anything coddle to use. Try modularity falls into your medulla. So the medulla has got two parts. It's got an open part on a closed past. The open part is the inferior limit of your fourth ventricle right here and then your closed far are these white matter traps that ascended? Those are your daughters columns that a centers you can see your physical is still is and you can nature's. But yeah, that's the fourth ventricle. Your inferior limit is called The old backs on the fourth ventricle is divided in half by this pharmacy Larrys. Anything inferior to it is part of the medulla. And that's the floor of the fourth ventricle where you can see a lot of outpouchings. You need to know what they are, but they're basically your cranial nerve nuclei. As you can see, you've got your hypoglossal here. You got your facial colliculus. But you need to know you need to know any of them on then finally in the midline, just as you had an anterior median Fisher posterially for your posterior median. Fisher. Technically, it's called your posterior median sulcus, but I don't think that matters too much. Then you've got just medial to that just lateral that you've got here. Bacillus lateral body, body of the nation. This is a listen up here in the nuclei and then they send after the devastating your medial meniscus. There, senators, pelvis and obviously the the CML pathways and the spinal pathways will be talking another lecture. But that's basically the high yield aspect off the of the brain. Senator know you need to know in terms of Canterbury identification off objects. Okay, So credit of movie, a very important to know where they leave the brain stem so off the 12 grain of nuclear one into a not bother Branston. The olfactory nerve and your optic nerve goes straight to the thalamus, or sometimes just even the cortex. Your third enough or your ocular motor nerve comes off the mid brain because that's where it's nucleuses on. I keep telling you that's where it comes off. It's called the Interpret, um, killer for PSA. As you can see, here is a your cerebral peed uncles and this coming out partying here is your third year from interview dot Hello, sir. Then your fourth Now also comes off of the midbrain inferior to the inferior colliculus. And it has a dorsal exit. So it exists from the posterior aspect, loops around the lateral aspect of the brain stem. And then you can see it. Anteriorly only credit love to do that. You got your 50 now for your trigeminal comes up on the entry lateral margins of your plans, then green love 67 and eight. They all can come out from the pontomedullary junction of the quantum Adoree Soltis on day are organized from medial collateral in the A sending order. So your sixth nerve is most medial collateral. That is your facial natural that is arrested Leukopenia Onda Junction, where the medulla, the ponds and the cerebellum eat is called your cerebellopontine angle. I don't know if you know about this, but there is a confirmation called vestibular Sonoma or or acoustic neuroma, and they are most most commonly found at the CP Angle or your cerebellopontine, which makes sense because they come off your 7th, 8th, 9th on that's that's what they're located of the CP angle. Then you've got your ninth nerve on your 10th nerve that comes off your posterial actual sulcus. As I said, they that's the sole cause between the pyramids and the olives on a very high yield. To know that, because just medial to that you've got your hypoglossal love, which comes off the anterior lateral sulcus. Thea the anterolateral, Arguably in between your periods of knowledge is lateral body and ninth and 10th. What confuses A lot of people are your accessory nerves because you've got both cranial roots and spinal roots, because the accessory nerve comes off from that. As you can see, a ventral route of see one C two goes up the foramen magnum in the posterolateral sulcus. Then it joins with the 10th nerve and then exits year the jugular for a man. So that's very high. Intimal. You need to know your pain. Then you clear. It's most common question to ask you about the brain stem is where they're located. So now I'll briefly touch upon the corticobulbar tract because this confused with the most Because anytime I thought about a descending track, I thought about the cortical spinal tract as we know you got an anterior lateral. They provide contralateral elevation most commonly affected in stroke, however, that those are not feel creative, nuclear only for your like muscles and everything else you've got your cortical bulb attracts, which are for your cranial own nuclear, especially the mortar ones. So it's a more detract. You've got an upper motor neuron in the lower portion you're on on. The pathway is similar. You've got your cerebral cortex, your first order in Iran. That synapses of the credit of nuclei in the NuvaRing of second order neuron goes to the effect is that's your pathway. Where I usually get confused was I never understood in terms of where does it Dec a state because it provides contralateral innovation just like the corticospinal try it. But what you need to know is each criminal of nuclear walking to each grade 11 you create. It receives, um, innovation from both hemispheres. So from your absolutely hemisphere receive innovation. And they're also received innovation from the contralateral cerebral cortex. That's important, because then, that makes you understand why only 50% of the fibers need to decorate. So let's say, for your left eye germinal mortar nucleus, you will have five is coming from the left cerebral cortex and the right cerebral cortex. The left cerebral cortex fibers will not need the dexa date on the the fighters from the rights record, actually, too. Seven the left regularly. And that's where you only have 50% of deca station of fibers because one of them is from the gives a Natural hemisphere. The other one is on the contract, have Astrea and then now in terms off. The level of mechanization are very commonly confused because most of your pyramidal tract deficit at your pyramidal tract infection, which is the inferior limit of the medulla. But your corticobulbar tract is different in the sense that it will only docusate at the level of the criminal of nuclear. So your third of nucleus and your fourth mile nucleus are in your midbrain, so the fiber is supplying them Will check a state of that level. But let's see your abductions Nuclear. So your facial of nucleus that's in your Contin region so they will consider the level of problems. However, you've got two exceptions to this rule, the volume Feitian of nuclear and hypoglossal nerve nuclei. They only receive contralateral innovation. Um, that means the only received it from the other from the opposite hemisphere. So all of their fibers will that will need to use it. And this was touched upon more in a trailer of mucus, cranial nerve electricity all just for that. And this is where the name comes off for pathology such as Boulevard and Pseudosbulbar policies because they affect these tracks a bulb. Our palsy is a lower motor neuron problem. And, as you know, from Ukraine, like as I talked about the pain of architecture, any nerve exiting the cranial Oh, nuclear is a little more urine, but so the boulevard called is a mortal Iran palsy, so only effects your upper motor neurons on. So that would be in your cerebral cortex or you're in telecasts field going down to Canada. Leave here. So I have talked for a while. A lot of high yields, topics time for five questions. No memory on day Aren't the easiest because Because if you if you can answer these, you can ask the easy ones. So obviously, the first question you can always you can write in the chance. What are the force of matter? More two nuclei off the brace them basically which is the most medial nuclei in your cranial of architect. That I just talked about is the number 123 or four. I'll give you, like, 30 seconds to drop in on the chat. Your answers to it or but yeah, yeah. So we've got a three in the chat also. Tough crowd. Only one response. So yes, you're you're not drunk. It is number three. So the four most medial credit of nuclear are your third Know your fourth. Now you're six now and then you're 12 now because they are ocular motor track are in order. Trochlea Abdus is the hypoglossal. They really only so obviously the first three nerves they talk about Go to your extra ocular muscles and in hypoglossal goes to the muscles of your tongue. And they are the most medial quinolone you pr in the brain stem. So this is like a bit of both off the following nuclei. What is the source off Preganglionic Parasympathetic axons traveling with this cranial nerve. So is asking you to things identify the cranial nerve and then identify which cranial nerve nuclei it carries its preganglionic parasympathetic axons from that has been ignored. Country. We had a tough crowd to use. Um, now, um Okay, come on. So yeah, I think so. So yeah. There you go. Finally. So it is number three because it is the facial nerve that comes off the Pontomedullary junction. The most medial being. Your abdomen is so your 60 now, just lateral the category of seventh now lateral, and you've got your ate enough. So, Abdus, in facial vestibular copia not pee ganglionic Parasympathetic Exxon's from your cranial. In terms of the Queen of Architecture, it's the second most lateral to your viscera mortar nuclei. And because of the rule of fours, you've got your reading a vest foul your superior salivatory You're in fear. Celebratory and your doors and Morton Nucleus of Vegas. You're super salivatory. Is your facial out? Your inferior salivatory is your ninth now, so that's preganglionic sympathetic present accent. So where does the hypoglossal now leave? The brainstem is the anterolateral Salt Coast, your posterolateral sulcus, your anterior median fissure? Or is it from the columns? Oh, because where they leave is very similar and great, like just nearby. Where the ninth and 10th now believes so. No. Yeah, exactly that if he is number one, it's your anterior lateral sulphus your anterolateral soldiers is The salt is between the pyramids and the olives. Lateral to the olives. Euphoria posterial actual sulcus. That's where your ninth and 10th nerve effects of the brain stem as well as your hypoglossal once it's right over your accessory nerve. Once it comes up, Do you have a loss of nervous from the anterolateral sulcus? Um, what are the influence of the nucleus? Tractor Solitary us to the nucleus. Practice solitary. It's if you remember, Is one of the Afrin nuclear off the brainstem? Yeah, mass. Correct. It is number three. As I said, it receives 739 to 10. It received taste information from the anti or two thirds from the seventh nerve posterior one third from the ninth and then received chemo receptor and mechanical receptor information from your chronic body 06 Sinus ease your GI tract and your heart and everything from the ninth on the nucleus. Practice on the terrace is an effort. Um, this is a bit of a clinical testing as well, because I talked about the corticobulbar tracks, But you want to be on this and, uh, no ski. I just put in there because yeah, so he's got. So this patient comes in with mixed motor problems. You have contralateral after motor neuron deficit. It's a natural tongue problems. Where would you expect to find the lesion? Was asked you a couple of things is asking me whether you know where your corticobulbar tracks, how they run. And also which perennial of nuclei supplies what muscle. And then from where there's a criminal nuclear, leave the breaks down. Yeah, that's absolutely correct. It is not the case. I'm kidding that that's wrong. International time you do is is your medulla. It's your hypoglossal nerve. That should be number two do politicized, but yeah, So the reason it's it's electoral is because all your long term you're on's go to this like our Exelon actual. But your contralateral are promote on your own deficit is because they state, but you're absolutely right. It isn't a dollar, it's 100. So now what I'm going to talk about next can be found in cross minutes and asked me, which is what We were recommended in 30 years, so I would recommend you use that as your Bible to basically learn all of your and asked me on. That's where these axial slices are. You don't have to know them in detail. The reason after them is because I'm a visual learner in terms of when it comes to and ask me. Obviously we know how it looks externally, but in like internally, it basically makes much more sense to me in terms of where the nuclei are and one of the tracks everything. But it's unlikely you'll be tested about this in your skis so I won't go into much detail. But everything in here goes from inferior to superior. So this is the inferior most axial sections off the middle, and the reason I can say that is because of a couple of things. Number one is your doctor. Station of Pyramids, as I said in the infield limit of the medulla, is either when it leaves the foramen Magnum or where the pyramidal tract check a state at the declaration the pyramids. Ideally, they should both line up. So you know that this is indeed it is the inferior to the medulla because that's where you see the pyramid on back a station. This, then, is your anterior aspect. This is your posterior aspect. The reason you know that is because you can see your physical is chrysalis on your fasciculus you nature's which is your daughter columns. And it's got the world docile in them because it's on the posterior aspect. Jobs they rise up. Posteriorly. That's your posterior median. Soul kissed. This is your anterior median. Fisher. You got your pyramids this on then that Don't that's your spinal salad. Better cerebella tract is, you know, if your anterior lateral so you're going to end dorsal spine is terrible attacks. That's your cereal arm, Central grey matter. That's your central canal, which is a continuation off your ventricles distally on. Then, as you know that these, like the dorsal columns, come up to the medulla. The synapse with their nuclear, as you can see and then from the nuclear you have your medial meniscus pathway on your internal are cute fibers that deficit and go up to the contralateral Thomas. And then from there, you know, it goes on through the sweeper cortex. So now we move up on our our up a level. You can see that you have your pyramids here. You've got your central grey here. But now what you can see is you've got your spinal tract off the trigeminal as well as the nucleus off spinal tract. Try, General, if you remember from the Queen of Nuclear Detector side the sensory nuclear to the trigeminal is three parts your spinal decrease your principal nucleus on your medicines of fallot thing clears on that that spans the level of the entire brain stem. So at every single level, off the brain stem, you will see a trigeminal nucleus, and the difference in the nucleus is final. Track on the spinal tract is simply the axons. So this the nucleus and that's the accents coming into the nucleus on. That's about it. That's really Central Canal. That's your daughter. Columns. This is your medial meniscus because the because the entire name of the doctor columnist the D CML attract Dawson call a medial meniscus pathway. The medial meniscus are over here, as you can see contains the second order in Iran's going up to the contralateral Salama's. So at this level, your daughter call, um, pathways that already dec assay tid hard. You know that because that's the internal, aren't you, fibers the deck estate middle and this guy's middle in this one goes all the way up to the contralateral Thomas. So those are the more in the main take aways, then another thing. So let's say you were given this thing axial sections the way to know that it's the medulla two ways. Number one. You can see the fourth ventricle on the dorsal aspect. As I said, the fourth ventricle is only either the ponds or the medulla on, but the way you know for sure that this is the medulla is this That's your inferior Olive, the urologist present in the most proximal part of the most rostral part of the medulla. So that's the fourth That's your posterior aspect of the fourth. That's your anterior pyramids. Lateral. Glad you brought your injury or lives. That's your anti elections all cause that you're posterial actual cell cancers. Now there's a lot of, um, like Martin. Like, was it all of these things here? You don't have to know all of them. He just need to know the main ones. That's the olive. That's your medial meniscus. It's immediately. You've got this thing, which is your nucleus? Raft magnets just in the center. Uh, it is one of the things you just need to know. Um, you've got three main ones. You've got your nucleus roughness. You got your locus, Really? It's. And the volume substantia nigra. The reason is, you know, those three things is because they are very important in terms of specific neurotransmitters. The nucleus raft Magnus is the most abundant producer off serotonin ergic neuron. So serotonin, your locus, the really assess is the most common way off off producing NORAD or north and jenaline. You're on's and I'll come on, I'll show you the locus related other sections and then lastly, body substantia nigra. That's in the midbrain on. But I'm not sure if you've got Parkinson's yet, But when you do Parkinson's, you know that that is what is affected. Your past compactor off your substantia nigra is dopamine. Urgent neurons to the striatum. The striatum contains your call it nucleus and your pertaining, which are your basal ganglia, which is why you have all your symptoms. So that's how you correlate and actually with your clinical symptoms. So you got the medial in this case, it between three or four lives. Now, as I said before the midbrain, is that the brain stem has got your internal white matter tract to create a nuclear. But it's also got the articular formation particular formation. As you can see here, it's marked. The ridiculous formation is we don't know anything about it. All we do know that it is a very high order thinking center, in the sense that not only does it have White Matter tracks, it's also got cradle of nuclear. But it would be impossible for us to name each one of them because it's more than 100 all you have to know it is got function and basically every high order thinking skill, memory off like talk a speech, everything vision, everything. But the most important one is consciousness Onda. That is what's affected in locked in syndrome, For example, when you've got a basilar artery occlusion or basilar stroke, or if you've got central 20 mile and license when you have immediate correction off hyponatremia, that's what's affected. Your particular formation thing is your fourth ventricle. As I said on the floor of the fourth ventricle, about multiple nuclear, you need to know what they are. But if you do want to most medialis hypoglossal nucleus, as you can see, it's immediately because it's it's a lot more damage is lateral the lab value in dorsal morton nucleus, which is your viscera mortar nuclei, which is just left over that. So that's how I remember the cranial of architecture, because that's exactly how it is in the actual sections on. Then most lateral, you've got your visceral sensory nuclei, which is your vestibular cochlea nucleus. It is always the auditory information balance and stuff on. Now, because we're near the olives on the pyramids, you can you can kind of guess that we're near the level of the cerebellum, peed uncles at the cerebellopontine angle and That's what you can see here. Your inferior cerebellar peduncle. I won't talk much about them, but all you need to know is the infusion. Develop a dunk. Oh is very important in terms of carrying the tract from your olive, all the all the very tract go through the cerebellar peduncle infusion therapy, uncle, into the side on then, also over here you can see you've got something called the medial longitudinal fasciculus on the left, the MLF basically connects your vestibular copy nuclear's with your nuclei off your external ocular muscles. That's your 3rd, 4th and 60 Prius. And that again goes back to the fact that when you're here in order to stimulate that, you can like, specially especially aware and then you can move your eyes to us. Now we're at the level of the ponds. How do we know we have a level? The ponds is because you can see the cerebellum. The cerebellum is attached to the ponds on the post reintegrate bombs. So when you take an axial sections, you'll see the cerebellum here. That's maybe that's that's your cerebellum cortex. That's identity nucleus 14, which you'll talk about tomorrow. Then you've got your middle cerebellar peduncle. But even out of that, the most common way of identified that this is the bones is by looking at the anterior aspect. If what a huge bundle of fibers. As I said in the anterior aspect of the ponds on, that's what two things Number one, it's, um it allows the corticospinal tracks to go up and down your cortical wanting tracks to go up down. But it's also got your Ponty nuclei from the point in nuclei. That's where your cortical ponting tracks coming synapse and then from the point of nuclear your body or transfers pointing fibers that go from the ponds horizontally into your middle cerebellar peduncle. And that is why you have these tracks called the pump. Oh, sorry. Better fighters. They arrived from the ponds. Go through the cerebellar peduncle into the cerebellum Just in continuation. You got your medial meniscus comes with the CML. We go to your left ear and anybody of four Sentra. As you can see, you still have the fourth ventricle here. Now you can see that this is the superior Sybylla Peduncle. So now you can appreciate that you were going higher up in the brain stem. You know what? You you have the continuation of the articular formation. You've got your 25 years and you're wanting nuclear front. You still have your medial and Miska that's going up. This is a good actually section because you can see from the anterior lateral large into the palms. You have your fifth nerve coming off. Um and which is why it's not showing here, But you have your trigeminal nucleus. I I I'm right there. One thing that isn't talking about, but I felt be good to know is something called your trapezoid body. Your trapezoid body helps in auditory still in auditory information capture so basically all the auditory information and come from investigate cochlea nerve goes up, cut um, synapse in with the trapezoid body and goes all the way to your inferior colliculus. And then from there it goes back to the fellows. Now we're reaching the limit of the of the upper limit of the ponds because you can see that the fourth ventricle is narrowing as you go up. It's becoming like this around central Canal, which is your appetite of Sylvia's. So your cerebral aqua, that's important because just surrounding your, like aqua Doctor, you Aqueduct is your periaqueductal grey matter. This is the start of it. And as I said before, just like you have the nucleus rough Magnitsky of the locust really is which is the origin off nor adrenaline unions. You have the like almost the superior limit of yourself Superior Savella peed uncles, you have your natural and discuss your natural amnesty is the is the track that goes from your trapezoid body that I talked about in the last line. It goes from your trap is our body goes all the way up to your inferior colliculus in the midbrain and then from the mid brain funding from the inferior colliculus, you have the break in inferior colliculus that goes to the farmers. You have, um, 11 in the medial aspect. And then these are your corticospinal corticobulbar tract in your pointing nuclear stress. Now we're at the midbrain. Almost done on. You've got in your midbrain, obviously, in the center. You got your cerebral aqueduct. You got your periaqueductal grey matter surrounding it, posteriorly, you've got your inferior colliculus. And as I said, inferior to the inferior colliculus is where the trochlea enough comes off of the drop in numbers going exit from here on the back. This is your anterior aspect. This is you know, I want to say this is exactly the mid brain because you can still see some of your pointing fibers. This is on the pontoon Cephalic junction on. As you can see, you have the superior limit of your superiors appeared. Uncles, you have left in the middle. Anybody? Very productive. Great matter. This is problem it brain on this really gives you an idea of what I talked about in terms of the vertical divisions of the brain stem. You have your basis in the front. You take mental in the middle and your tectum at the back. So you're tectum would be anything posterior to your city. Well, acted up to this would be your cholesterol. I all of these, all of this would be your tegmentum. And then all of this would be your basis. So we're going from anterior posterior your body across three Bryant. All of these tracks, as you can see, your front upon contract to college ball, back article, spinal tract and everything over here is the substantia nigra. As I said, the opening allergic um neuron, go from the past compactor off the substantia nigra to your debate structures, and it's, that's that. That's what it's affected in Parkinson's. And so when you do Axio histology like this in Parkinson's, you have you see a trophy on degeneration of the substantia nigra. Um, they're like, continuing. You can see you are your media lunch, you know, particulars. Here you have your medial meniscus, which is your daughter Pathways going up and you've got your super superior. Cerebellar peduncle is there are about to finish. That's your inferior colliculus on. But just like a Z saw in the medulla, you also have another after nucleus, which is your start time. Now we have the level the superior colliculus basically at the top off the brain stem. Um, you have your periaqueductal grey matter. You have your sleep. You have your basis here, which is your substantial nigra. Your cross three Brian. Very important thing to know at the level the superior could collect. This is your red nucleus right in the center of your tegmentum. The red nucleus are you will be talked about. I think in your spinal pathways because that's where your rubrospinal pathway comes off your rubrospinal pathway in your central take mental pathways come off the red nucleus, and they're involved in fine motor function on so many fibers that come off the red nucleus. Deck a state anterior to it, and it's called a ventral take mental area of eventual take mental decoration obviously had 11 superior collect list. We've got your ocular motor nucleus as well as you're adding our best phone increase. That's where the third nerve comes off on on. Obviously, as you can see the fibers of the ocular motility, because these are your cerebral Pete uncles, the interpret, um, killer fossa and your third of comes off. I think that's is yes. So a lot of theory aspect on hopefully have been able to give you a better idea off where everything is located. There's the last ways last five questions, and hopefully after this you will be, um, good enough for any brace anatomy questions. So consider this nucleus on. Where does it axon exit the medulla? So already this question's told you about localization? Um, it's in the medulla on. You need to know what you need to break down the question. Fundamental in the What's asking is given your location and it's highlighted a nucleus. So now, in terms of thinking about your cranial of nuclear architecture from medial collateral, what do you think it is? And once you know what cranial, Um, nuclear itis. Where do those fibres exit the medulla? That is what the question is asking. And so it's a combination of both your external anatomy as well as the internal, and ask for your brain. We have no takers and see how it is. Number four. Yes, that is correct that on the level of the middle, that's your fourth ventricle. You can just see your olives here most immediately. Is your PSA matter motor nuclear, The hypoglossal lab. So your 12th. Now that right there just lateral to it is your door. So more so. Nucleus of the vagus. And so because as the hypoglossal nuclear, you know, it comes up the international sulcus, which is in between the pyramid, the olives, my stuff, another one. I've just mentioned this where the axons off this nucleus terminates. Um, So look at the look at the actual section. Think about which nervous is Onda. Then I was like What? To So yes, So yes and no. So this question stumped me a z Well, because I was very proud of how I made the question. Um, no, I'm cutting and cutting appointment, but so the question is asking where the axons off this nucleus terminate. So you're right in thinking that any preganglionic paris and but said it parasympathetic nerve is going to come off this nucleus. You're right, because that's the dorsal mortar nucleus of the vagus where it's asking where do the axon off that nucleus terminate. And as I said, any central nervous system parasympathetic nerve, which is your seventh of your daughter, Fanjul, your vagus. They all terminate in ganglion um, your ganglion, your terrible Palatine dangling in your ciliary gangland. So these axons will terminate in postganglionic parasympathetic ganglion. So it will start off these nuclear as frequently on it. But they will terminate that paused ganglionic parasympathetic ganglion because once in terminated and gangland, then you have the terminal fibers that go and innovate those specific, less same muscles or those specific mucosa or those organs. In the case of this. Okay, so that was a big trigger. Um, this one should be relatively simple, which quick, which 15 of censor nuclei receives, like touch. So you've only got three. So you're, like, 33% chance of getting them, right? Yes, I was correct. It is your principal nuclear's. So if this is a refresher, your spinal nucleus is your pain and temp. Your principal nucleuses like touch on your medicines of Alec nucleus is proprioception. How I remember it is proprioception is a very long word. And that is the same as the longest 50 nerve center nuclear. Your ms is how I remember like touch and principle is LP for lumbar puncture, light touch for Ellen, people principal. And that that just works for me if it works for your rate, this Final one and I've mentioned it a few times. But what sensory information does the inferior colliculus receive? Yeah, that's correct. It receives your auditory new auditor information on your superior colliculus is what receives your visual information, including your gaze centers. Yeah. And then, as I said from the inferior colliculus, you have the great, um, inferior colliculus that goes up to the medial geniculate nucleus off the thalamus on. Then it goes on from there to the cerebral cortex. Um, I think it's a lot of questions. Um, but last, where is the fourth ventricle located? So that's correct. It is located in your palms on medulla. Because if you remember, you've got your third ventricle in a diet supplement. Your midbrain only has your cerebral could opt for the aqueduct of Sylvia's. And then your fourth ventricle is divided into half by your striatum. A generous anything rostral with trying the gel are Is anything rush into it off The fourth ventricle is your palms. Anything doors, anything distal to it is your medulla? Um, yeah. So actually right here. Point of dollars where you're 400 was located distilled the medulla. Is your spine up? Yeah. Thank you, everyone for listening. I hope I haven't bored all of you. But that's my email. If you want to send me a a, drop me and email about anything osteo related, not ask your life that I'm happy gone, sir. On that is the link. Utah. Utah. I think you can share that on. But that's the link for tomorrow's cerebellum lecture that will be given by two speakers on. But I hope to see all of you there. All the slides will be uploaded. I've only been going on the chat, so really There. Okay, so all the sides will be uploaded on day. Once you fill in the feedback forms, you get your certificates and the sides. This is being recorded. I do appreciate the fact that not that there wasn't a lot of information the side Because I'm a visual learner. Which is why we will expedite the upload of this lecture on two medals. You have access to that? Um Andi? Yeah. I hope you enjoy it now. I hope I have simplified it enough. If you have any questions, feel free to email me and we'll see you all tomorrow. Same time. 6. 30.