all right ninja nerds in this video today we are going to talk about the thalamus we're going to get into tons of detail on all the various nuclei their overall functions i just want to give a big shout out because this video that we're going to do on the thalamus today is because of one of our ninja nerds aim so because aim is one of our master ninja nerd kind of level members he requested that we make this video on the thalamus and you guys can also do that too if you guys go down in our actual description box we'll have links to our youtube page where you guys can sign up become members if you guys want to request some specific videos we have different levels that you guys can join and we can try to connect with you all right so let's go ahead and get started on the actual thalamus all right so let's get started on the thalamus now the thalamus is actually you know when you're learning about it it can be quite daunting especially when you look in the books and they got like these millions of nuclei you're just like what the crap is going on so what i really want to do is is i want to talk about all these thalamic nuclei and their functions but i think the best way to learn them is to separate them based upon what kind of information they're acting as a relay station for because that's the basic thing if you guys don't remember anything out of this video i want you to take away that the thalamus is a relay station basic function is it's a relay station for three types of information one limbic system information two sensory information three motor information it's taking that information and sending it to the cerebral cortex that's the basic outline of this video but now what we got to do is is really dig into the types of limbic information types of sensory and types of motor information that the thalamus is acting as a relay station for all right let's start with the first couple phthalamic nuclei there's three particular thalamic nuclei that are involved in the limbic information that it's a relay station for so let's go ahead and talk about the first one the first nucleus that i want to discuss here is very cool i really like this one it's called the anterior phthalamic nuclei let's kind of show you where that is okay so if you look over here we have a little diagram here okay this is the thalamus this is kind of the view of the thalamus it's an egg-shaped structure and it's divided into three different kind of nuclear groups by this little y-shaped structure this y-shaped structure is actually called the internal or medial medullary lamina so what is it called it's referred to as the internal medullary lamina or again sometimes it can be referred to as the medial medullary lamina what the nice thing about this little internal medullary lamina is is that first thing it's actually a white matter structure okay so it's myelinated axons the second thing that's really cool is it separates the thalamus into three different nuclear groups the first nuclear group we're going to talk about here is called the anterior nuclear group that's the first one that we're going to focus on the other nuclei that are actually important to the limbic structures of the thalamus is going to be another one so if you look here we kind of have a little directional kind of anatomy here right so this is the anterior portion of the thalamus posterior portion of the thalamus lateral portion of the thalamus and the medial portion on the medial side okay right in here you have a specific nucleus that we're going to discuss next after the anterior thalamic nucleus and this is called the medial dorsal nucleus so this is called our medial dorsal nucleus or sometimes referred to as dorsomedial nucleus the last nucleus that i want to talk about here is actually kind of lodged within the internal medullary lamina so all of these little dots in here called your intra laminar nuclei right so they're little gray matter structures that are kind of dispersed through this internal medullary lamina there's one particular interlaminar nuclei that we really want to focus on here because it's involved with limbic system information and this one here is called your centro median nucleus centro median nucleus okay so there's three particular nuclei that we're going to focus on here on the limbic nuclei of the thalamus the anterior thalamic nucleus the medial dorsal nucleus or sometimes referred to as the dorsal medial nucleus and a type of interlaminar nucleus which is called the centromedian nucleus let's start discussing the anterior thymic nucleus so the basic thing i want you to remember with the anterior thalamic nucleus is that this is involved and particularly a special type of circuit that we're going to discuss here and this circuit is called papays circuit okay it's called papays circuit and papaya circuit is important because this this circuit is involved in what's called episodic memory but particularly the emotional involvement of episodic memory so it's involved in emotional emotional episodic memory this is very very important you want to know why we're going to talk about the circuit but if there is damage to the papae circuit and you have loss of this emotional episodic memory there's particular diseases that can be affected within this pepe circuit you know what you know what kind of diseases can actually uh manifest whenever there's damage to the pepe circuit it can be diseases like alzheimer's because we already know that alzheimer's disease is basically a disease of one of the memory aspect okay the other one is parkinson's disease so parkinson's disease is also another one that can be affected okay and the other one that's actually very interesting is called corsicoff syndrome okay so corsicoff syndrome korsakoff syndrome is actually due to usually in alcoholics corset cough syndrome and this is usually due to a thymine deficiency so what i want you to know is that the antithyromic nuclei is involved in the emotional episodic memory via the circuit called the papay circuit whenever there is damage of this circuit there's loss of episodic memory and conditions such as alzheimer's parkinson's and corso cough syndrome let's dig into this pepe circuit if you look here we have a sagittal section of the brain right and then we got these little things hanging off here that's our pituitary gland and then we have this other structure here called the mammillary bodies if we look in here we got a couple structures here that i want to define first obviously this right here is our thalamus and the nuclei that we really want to focus on is right here that anterior thalamic nuclei this structure here is called the corpus callosum so this is called our corpus callosum it's a commercial vibrant connects both sides of the cerebral hemisphere right there's another structure above that just above that and this is called the cingulate gyrus so this is called the cingulate gyrus and then so we have our thalamus we have our corpus callosum we have our cingulate gyrus then you have this green structure here this green structure is very very important this green structure is called our hippo campus the hippocampus is a very important structure involved with our memory there's another structure underneath that we'll talk about this in a second but it's called the into rhino cortex the into rhino cortex but we'll talk about that in just a second what happens is the hippocampus is involved with memory storage there's a structure that takes information from the hippocampus and what it does is it takes that information the memory information from the hippocampus moves upwards past the corpus callosum and then comes over here and synapses on the structures here of the mammillary bodies these are your mammalian bodies what happens is these neurons in the mammillary bodies then once they're stimulated from the what's this what's this orange structure called very important structure this is called your fornix this is called your fornix so from the hippocampus the fornix connects to the mammalar bodies stimulates the nuclei of the mammalian bodies guess where the mammalian bodies go to they send their fibers to the anterior thalamic nuclei so here we're going to have our anterior thalamic nuclei what is nuclei it's a group of cell bodies present in the central nervous system so from these fibers from the mamillary bodies you stimulate the anterior thalamic nuclei the anterior thalamic nuclei then send their axons upwards and guess where they go to the cingulate gyrus the cingulate gyrus which is another important component of the limbic system sends its axons downwards we're going to follow this down here through the cingulate gyrus all the way down here and guess where it moves to it comes around here and stimulates this little brown structure what do we say that brown structure was before we called this brown structure here the into rhino cortex this is a little structure that's a part of the para hippocampal gyrus we're not going to get into tons of detail on that but what i want you to know is that the enterorinal cortex has little neurons that guess what it connects with the hippocampus what is this it's an entire loop it's a circuit so i want to recap this this is a very high yield thing what is pape circuit involving emotional episodic memory hippocampus involved in memory sends information via the fornix to the mammillary bodies mammalary body sends their mammal ophthalmic tract to the anterior thalamic nuclei anterior thalamic nuclei send their information to the cingulate gyrus cingulate gyrus sends its information down to the into rhino cortex and the into rhino cortex particularly what's called the perforant pathway sends its information and finishes the circuit in the hippocampus the whole purpose of this circuit is emotional episodic memory boom roasted we killed the anterior thymic nuclei let's move on to the next one which is the medial dorsal or dorsal medial nucleus all right so we talked about the anterior thalamic nucleus the other one we got to talk about is this dorsal medial nucleus or medial dorsal nucleus let's just put medio dorsal nucleus but just to remember they are interchangeable okay so medial dorsal nucleus or dorsal medial nucleus if you look at it where its position is here we already talked about the anterior thalamic nucleus we already discussed that one above this is the medial side this is the lateral side of the thalamus so where would you find it you would find it right here that's our medial dorsal nucleus the medial dorsal nucleus is another important component of the limbic system but a particular aspect of it so what we really need to know is three important things this is obviously involved with emotions it's involved with your emotions particularly obviously at the emotional aspect of memory it's involved in motivation and it's involved in your overall drive okay so i want you to remember here let's actually be specific here not just emotions itself but emotional memory so it's involved in emotional memory motivation and drive whenever there is damage to them dorsal medial nucleus or the medial dorsal nucleus it can affect our emotional aspect of memory it can affect motivation it can affect our drive and lead to a lot of personality changes you know what kind of disease actually loves to affect this area of the thalamus we already talked about it above corsical syndrome so whenever someone has a severe thymine deficiency right so this is a thymine deficiency vitamin b1 severe deficiency of thymine this can affect not only the papaya circuit but it also can affect the dorsal median nucleus okay so let's talk about some of the structures that are connected with the dorsal medial nucleus so what you need to remember is that the dorsal medial nucleus or medial dorsal nucleus receives three particular sensory information or three particular afferents one we already talked about it already what was this structure that we talked about above we'll send its information about memory emotional aspects of memory in this case to the dorsal median nucleus the other structure here you see this little kind of maroon shaped structure this is a very important one this is called the amygdala right so the amygdala is also a very important component of our limbic system it's involved with kind of fear anxiety aggression a lot of that types of emotions so it will also send its information to the dorsal medial nucleus and then there's one other one you know the hypothalamus the hypothalamus has multiple different nuclei and multiple different types of functions but it's also another limbic nuclei structure it can send information to the dorsal medial nucleus so there's three structures i want you to remember that its sensory information or send its afferents its inputs to the dorsal media nucleus first one is the second one is the amygdala and third one is the hypothalamus now once the dorsal medial nucleus receives all of this input it takes that information and sends all of this information about emotional memory motivation drive fear anxiety aggression all of that stuff and sends it to a particular area of the cerebrum you know this area of the cerebrum very very important for you know attention for personality for abstract thinking as well as a lot of aspects of our emotional important component of memory you know what this green structure is called here this is called our prefrontal cortex this is called our pre frontal cortex sweet so again the inputs are going to be the hypothalamus the and the hypothalamus and then the output after it receives all of this information is to the prefrontal cortex beautiful that's our dorsal median nucleus or medial dorsal nucleus now let's talk about the last one here which is the centromedian nucleus all right so the last one that i want to talk about since we talked about the anterior thalamic nucleus the dorsal medial or medial dorsal nucleus the last one is your centro median nucleus and what did i say this was one of the intralaminar nuclei so if i really quickly draw that structure there right so here's our internal medullary lamina or your medial medullary lamina here right there's all these nuclei we talked about the intralaminar nuclei okay the big one that i really want us to focus on here is called the centromedia nucleus but just for your own edification what are the names of another one of those interlaminar nuclei there's two types one we already talked we're going to talk about the centro median nucleus the second one is called the para fascicular nucleus and we're not going to really focus on that one a lot but i want us to know that there is different types of land interlaminar nuclei we're going to focus on central medium but the other one is the parafascicular nucleus all right so here we're going to draw that big old central median nucleus right here okay within that internal medullary lamina what is the job of the central median nucleus here's what i want you to know it receives information via your slow pain pathways so it receives information via the slow pain pathways what are what are the pain pathways do you remember what the name of that pathway is that is the spino thalamic tract and if you guys remember which type of fibers actually carry this slow pain is it the c fibers or the eight delta fibers it's the c fibers right so this structure here these centromedian nucleus will receive information so here we're going to have some type of pain stimulus that pain stimulus is going to activate what types of fibers c fibers this is our c fibers the c fibers will come into the actually the posterior gray horn and we know the synapse in the posterior gray horn cross over and then ascend up whereas as a part of our spinal lemoniscus so this will actually be what's called our spinal luminiscus now we know that as the spinal meniscus sends upwards it gives off little collaterals to the reticular formation some of it gives off spinal reticular fibers but the spinal meniscus eventually some of these fibers will synapse and end on that centro median nucleus and some of the fibers from the reticular formation may also give some information to the central median nucleus now whenever the central median nucleus receives this pain pathway information particularly slow pain pathway information it then sends this information to non-specific cortical areas so it's going to send this to non-specific so what does that mean it means we don't really know it since it's a whole bunch of different areas in the cerebral cortex so non-specific cortical areas one is believed that it can actually send it to the cingulate gyrus why is all of this important the centromedia nucleus it takes pain and actually applies an emotional aspect of it that's why we believe that one of the specific areas that it actually goes to one of the specific areas is called the cingulate gyrus now remember what i told you the cingulate gyrus is involved in our limbic system that's emotions so technically this central median nucleus is believed to be involved with the emotional aspect of pain boom roasted all right so we've covered the main limbic thalamic nucleus the anterior medial dorsal and the central median nucleus let's now move on to the sensory thalamic nuclei all right so let's get into detail on the sensory thalamic nuclei all right so let's kind of talk about some of the basic anatomy of it we'll pick out some of those structures that we're going to talk about in this sensory atomic nuclei portion so again giving the orientation of this thalamus here this is the anterior portion of the thalamus posterior portion of the thalamus medial portion of the thalamus and lateral portion we already discussed the anterior thalamic nuclei we already discussed the dorsal medial nucleus or the medial dorsal nucleus and we also talked about one of the intralaminar nuclei which is the central median nucleus if you guys really remember one of the other ones was the parafascicular so now we kind of got a couple other structures left all right here you're going to have this whole group here this whole group here is called your lateral nuclear group but what we do is we split the lateral nuclear group into two components okay this dorsal component and this ventral component or anterior posterior component the first come thing that we have to talk about is in this ventral there's a bunch of different types of nuclei i'm going to i'm going to abbreviate them but we're going to talk about them throughout the process of this video the first nucleus here is actually going to be most anterior in this lateral nuclear group this is called the ventro anterior nucleus if you move a little bit kind of like lateral to that you're going to have a ventral lateral nucleus move a little bit more you're going to have what's called the ventroposterior lateral nucleus and then you have one more which is kind of creeping back here which is called your ventroposterior medial nucleus so again four particular nuclear that are located in this lateral nuclear group but in the ventral portion it is ventral anterior ventral lateral ventral posterior lateral and ventral posterior medial the two that are going to be involved in sensory activity is the ventral posterior medial and the ventral posterior lateral the ventrilateral and the ventral anterior are your motor nuclei of the thalamus okay cool so that's two of them there this nuclei back here in this dorsal aspect of this lateral nuclear group this thing here this is all called your pulvinar nucleus so what is this called this is called your pulvinar nucleus this whole area back here now there's two other ones again if you look at the thalamus this is the medial side this is the lateral side okay you have these two little nuclear that are kind of coming off the back of the thalamus one's a little bit more on the medial side one's a little bit more on the lateral side these ones here i'm going to abbreviate them but we'll write them out later this is called your medial geniculate nucleus okay this one here since it's a little bit more lateral this is called your lateral geniculate nucleus okay so the pulvinar nucleus is a type of sensory nucleus of the thalamus lateral geniculate is a sensory nucleus of thalamus and the medial geniculate nucleus is a sensory nucleus to the thalamus so how many of these nuclei do we have to talk about one two three four five okay let's first start off here with the lateral geniculate nucleus okay so the first one we're going to discuss here is the lateral geniculate nucleus basic thing i want you to remember i don't want you to have to remember tons because there's already so much information that you guys are having to absorb right now basic thing i want you to take away from this lateral geniculate nucleus is it involved in the visual pathway okay so this is involved in vision that's it i don't want you to have to remember too much so lateral geniculate nucleus visual pathway okay how does this all work okay oh and another way to remember this this is how i tend to remember this because sometimes people get confused with the medial and the lateral how do you remember i remember l you can remember light so light kind of helps you to kind of idea uh remember the idea that that's kind of responsible for vision so that's kind of how a little trick that i helped to remember the difference between the later geniculate and the medial geniculate nucleus so remember lateral light vision okay so you have some type of visual stimulus that visual stimulus what does it do well it actually is going to hit our retina when it hits the retina the retina will then become activated and send impulses down the optic nerve from the optic nerve it'll actually branch it'll actually bifurcate there's different types of fibers media and lateral fibers but eventually they'll move through the optic tract and go to this nucleus here hanging off the side of the thalamus what is this nucleus here called this is called your lateral geniculate nucleus it receives this information and some of it can send into the midbrain but the other thing it's going to do is it's going to take this visual stimulus and send this to a particular area in the occipital lobe you know what this area the occipital lobe is called this here is called your primary visual cortex so this is called your primary visual cortex what is this called primary visual cortex sometimes referred to as broadman area 17. if you really want to i'll put down number 17. but what do i want you to really honestly take away from this laddergeniculate nucleus is responsible for taking information with respect to the visual pathway and sending it to the primary visual cortex so that we can send that and have perception of the visual stimulus done let's move on to the next nucleus and the next nucleus that i want to talk about here is the medial geniculate nucleus so this is called the medial geniculate nucleus now the medial geniculate nucleus this is involved in the auditory pathway so this is involved in the auditory pathway or hearing okay how do i remember this m music so you can also remember the m here is music and that music is kind of tied to hearing so whenever you remember ladder geniculate l light medial geniculate m music kind of helps you to differentiate that so the medial geniculate nucleus if you guys remember we talked about honestly some of this stuff should actually click because we already talked about a lot of this stuff in the visual pathway the auditory pathway what happens here is you have that nerve what is that nerve that picks up that sensory information from the inner ear that's your vestibulocochlear particularly the cochlear division takes that information via cranial nerve eight and synapse is where synapses on the cochlear nuclei present in the pons medulla junction from these cochlear nuclei what do they do they send these fibers that cross upwards right and what does this thing what does this whole kind of crossing structure form it can form what's called the trapezoid body we talked about that in the anatomy of the medulla some of these structures will actually give off fibers to what's called the superior olives but the basic concept here is that after this trapezoid body is formed it then ascends upwards what is the name of this track that ascends upwards after crossing this is called your what is this lateral lumeniscus now the lateral and meniscus what we'll eventually do it'll synapse on this structure here located in the midbrain and this structure here located in the midbrain is actually called the inferior colliculus what is this called here this is called your inferior colliculus both of these they're paired the inferior colliculus will receive the sensory information of auditory stimulus and then via the brachium of the inferior colliculus will synapse on these little bodies here coming off the thalamus what are these little structures here called this is called your medial geniculate nucleus the medial geniculate nucleus will then send its radiations here to what area the temporal lobe the primary auditory cortex mama that should make sense so the medial geniculate nucleus sends its information to the primary auditory cortex for us to be able to perceive the things that we are hearing so the primary auditory cortex you guys remember there's what's called that transverse gyrus of hashel we talked about there if you guys really want to know the broadband area here is also known as 41 42. okay but again i want you to primarily know the primary auditory cortex all right so we talked about the lateral geniculate nucleus we talked about the medial geniculate nucleus lateral light that's vision medial music ears that's for hearing the pulvinar nucleus is actually really interesting and again remember where that that structure is that pulvinar nucleus kind of makes up that entire dorsal aspect of the lateral nuclear group the pulvenar nucleus is really cool so here's our pulvenar nucleus let's draw this one here we're going to shade this end here in blue right it receives information from this nucleus what is this nucleus here this is the medial side this is the lateral side this is anterior of the thalamus this is posterior of the thalamus so this is our medial geniculate nucleus this is on the lateral side so this is our lateral geniculate nucleus the medial geniculate nucleus which is taking auditory information it sends that information to the what structure here to the pulvenar nucleus the lateral geniculate nucleus it sends its information what kind of things visual information to the pulvinar nucleus there's two other structures you know down here at the level this is our midbrain all right so this is our midbrain obviously this is our pons and this is the medulla so in the back of the midbrain you have these two structures here this is called the superior colliculus and this is called the inferior colliculus the superior colliculus and the inferior colliculus both send information to the pulvinar nucleus so there's three or actually technically four inputs to the pulvinar nucleus the medial geniculate nucleus four auditory pathway ladders are nickely nucleus four visual pathway and superior colliculus is involved with reflexive movements of the head from a visual stimulus inferior colliculus is reflexive movement of the head with response to a auditory stimulus so this sucker is receiving both auditory and visual stimuli and guess what it does it takes that information from the pulvinar nucleus and sends it to two areas in the occipital lobe we already talked about one of them the primary visual cortex that's this one here and if you guys really remember the numbers it goes 17 18 19 right so primary visual is 17 18 is your association well actually 18 and 19 are both a part of your visual association area so what i want you to remember is primarily 18 and 19 which are your visual association area are receiving information from the pulvinar nucleus now the pulvenar nucleus is receiving all this auditory and visual information guess what it's particularly involved in it's involved in what's called visual processing now that might seem just like very vague let me explain what i mean the visual association area takes particular past experiences with a visual stimuli maybe someone's face so they they have your past experiences of someone's face or maybe even a flower and it helps with recognition it gives meaning to that image so it helps us to recognize and perceive particularly the meaning behind the color the movement the different types of facial expressions so that is important so it helps us to be able to see someone's face recognize that we've seen that that face in the past and give meaning to it that is the job of that visual association area and who is it receiving its information from the pulvinar nucleus boom let's move on all right so now let's talk about the next nucleus here this was in that ventral component right the ventral component of the uh the lateral nuclear group this is called we're going to cover the ventro posterior posterior lateral this is one heck of a name nucleus you see why they just write it as vpl now so the ventral posterior lateral nucleus let's take a look here so if we take a look at this structure here this thalamus this is the lateral sides over here the nucleus is going to be right here so we're just going to kind of shade one in here this is going to be our ventral posterior lateral nucleus all right the ventral posterior lateral nucleus i want you to remember that it receives sensory information but since we're information from what you guys know this stuff already so it's going to be a very quick recap it is from our dorsal column medial meniscus pathway what is that pathway responsible for i know you guys know it this is involved with proprioception it's involved in fine and discriminative touch it's involved in vibration sense all of that stuff is getting sent up to this nucleus the other one and i know you know this one is called your spinal spino thalamic tract and i know that you know that there's two parts to this one the anterior portion and the lateral portion you guys know that the lateral portion is involved in pain and temperature the anterior portion is involved in crude touch and pressure what i want you to remember and we're not going to go into crazy detail but this structure these nuclei are receiving information so if we kind of recap it what is it receiving let's put over here pain temperature crude touch and pressure all of this stuff is going to be going via your spino thalamic tract and what that does is it sends information to the posterior gray horn crosses over if it's the pain and temperature it goes up lateral if it's the crew touch and pressure it goes to the ventral but then eventually ascends and they both fuse together and eventually terminate on that ventral posterior lateral nucleus and the same concept here you're also going to have what else fine touch and i'm not going to write it up a discriminative touch proprioception and vibration sense all of that stuff is going to get picked up and carried via what pathway the dorsal column medial meniscus pathway that will move into the posterior gray horn move into your what structure here and move into your dorsal white column ascend upwards to the medulla synapse on the different types of nucleus gracilis nucleus fasciculus i mean a nucleus connectors nucleus gracilis and we know here that they cross and ascend upwards and then terminate on the ventral posterior lateral nucleus where does the ventral posterior lateral nucleus send that information to the cerebral cortex but you know what areas of the cerebral cortex because we're an engineers we got to know all that stuff right it sends it to your primary somatosensory cortex what cortex your primary somatosensory man this is so much writing sensory cortex what broadband area is this three one two so three one two is your broadband areas for this one as well so that's what i want you to know for the ventral posterior lateral nucleus boom let's move on to the next one all right so the last sensory thalamic nucleus thank the lord this is going to be the ventroposterior medial nucleus what is this called the ventro posterior medial nucleus oh again he understand why they just put like you know vpn all right so the ventral posterior medial nucleus now we have to kind of again understand that orientation you guys remember these are the lateral sides of the thalamus and this is our whole lateral nuclear group right the ventral posterior lateral nucleus will be over here right we already talked about that one let's just say here we're going to do this one here in this kind of dark green here this structure here the ventral posterior medial nucleus it should be more medial in respect to the ventral posterior lateral nucleus now there's two primary sensations that the ventral posterior medial nucleus receives one it receives information via what's called the tri gemino thalamic tract do you guys remember what the trigeminal thalamus track picks up it picks up all the different types of sensations from the face right so it picks up pain temperature proprioception vibration sense all of that stuff it's picking up that sensations from the face the other type of sensation that we're picking up as we're picking up gustation gustation is your taste sense and that taste sense is actually being sent via multiple you know there's different cranial nerves you have your facial nerve and your glossopharyngeal nerve and your vagus nerve they're picking up all the different types of taste sensations from your gustatory receptors and sending that to a particular nucleus called the nucleus of tractor solitarius so two types of sensations taste and pain temperature proprioception all the different types of sensations of the face again we've already covered all of this stuff in crazy detail but all of these facial sensations all of them are carried via the trigeminal nerve now the trigeminal nerve has its fibers here right and what it does is it kind of gives off what's called the trigeminal tract and these trigeminal tract fibers can once this is you this is your sensory fiber right so this is the sensory component of the trigeminal nerve it's sending information to the central nervous system in this case the brain stem that sensory information will then move into the different types of nuclei here the cranial nerve nuclei of five particularly right so this is your mesencephalic your principle pontine and your spinal nucleus of the trigeminal nerve as it ends and terminates on these nuclei these nuclei give off their efference and these efferents travel upwards and synapse on what structure the ventral posterior medial nucleus so again you have the facial sensations traveling via the trigeminal tracts to the trigeminal nuclei and then upwards via the trigeminothalamic tract to the ventral posterior medial nucleus boom so all your taste sensations right so you know the taste sensations that's being carried by what different cranial nerves cranial nerve seven right that's the anterior uh two-thirds of the tongue cranial nerve nine that's your glossopharyngeal the posterior one-third of the tongue and even a little bit from the vagus nerve from the epiglottic follicular and even a little bit of the posterior oral pharynx all of that information is being sent via these cranial nerves and terminating on a particular nucleus here called the nucleus of tractus solitarius then from this nucleus of tract to solitarius it can send fibers upwards we don't really need to know but it's called the central tegmental tract and that central tegment here i'll just put it central tegmental tract it'll ascend upwards from the nucleus attractive solitarius in synapse on that ventral posterior medial nucleus then where will the things from the ventral posterior medial nucleus go to all the different areas of the cerebral cortex in this case it may go to the primary somatosensory cortex primary somato sensory cortex and again what is that broadband area just for the heck of it three one and two all right thank the lord we're at the last motor we're at the last nuclei of the thalamus okay so the motor thalamic nuclei let's talk about these so we've already talked about the limbic the sensory let's take it home let's finish it we're so close guys all right quick recap with all these nuclei we already talked about this anterior posterior lateral medial right this was our anterior thalamic nuclei this was our medial dorsal nucleus our dorsal medial nucleus this here was our pulvinar nucleus this was our medial geniculate nucleus this was our lateral geniculate nucleus so now we also have to talk about these other ones we kind of highlighted them but we haven't discussed them the ventral anterior and the ventral lateral nucleus but we did discuss the ventral posterior lateral nucleus and the ventral posterior medial nucleus and we also talked about the intralaminar nuclei with the paravesicular the centromedian but we've primarily focused on that centromedian nucleus right so we've talked about a ton of different nuclei let's finish it let's take it home and finish up talking about the ventral lateral and the ventral anterior nuclei these are motor nuclei all right so let's first discuss discuss the ventral anterior nucleus all right sweet so this is a motor nucleus so here we have to kind of again show it here so this is we're only showing one thalamus just for the sake of the diagram here so again this is anterior posterior medial lateral this is a part of the lateral nuclear group and it's going to be the most anterior portion in that lateral nuclear group so there's our ventral anterior nucleus the ventral anterior nucleus receives input from one particular structure the basal ganglia the basal ganglia is something that we have to kind of dig in in its own video it's way too much to discuss here we're going to cover the literally the basic concept here what i want you to know with the ventral anterior nucleus is that it receives information from the basal ganglia and sends that up to the cerebral cortex the whole purpose the whole reason for that is it plays a role within the initiation so the initiation and a very important thing and planning of movement that is very very key that's what i want you to take home with this so again input is from basal ganglia output is to the cerebral cortex particularly the pre-motor cortex we'll talk about in a second and its primary function is for initiation of movement and planning of the motor movement all right so let's talk about this basic basic basic basic here we have our cortex right okay here's our cerebral cortex and there's different areas pre-motor primary motor the somatosensory area all of those different areas they send their motor plan so are there basically your motor plan is if i want to flex my uh my bicep right i have a particular motor plane that my primary motor cortex has a plan for okay what the primary motor cortex and premotor cortex and all those areas do is they send that motor plan down to the basal ganglia and when it does that it can synapse on different neurons in the basal ganglia like maybe the putamen or the putamen and that structure will then synapse on things like the globus pallidus internis and then from the globus polytus internist it may go in synapse on the thalamus and what happens during that pathway is that there's different types of neurotransmitters that are released and the whole purpose is once this motor plan comes down to the basal ganglia the basal ganglia sift through all that motor plant information motor plant information and send that information to the thalamus and from the thalamus back to the cortex via this pathway this pathway here this one that we talked about here and the most basic concept is called our direct pathway and the direct pathway is designed to basically amplify your motor movements okay so and help to amplify what we already have planned another thing that can happen is is that these cortical fibers coming down to the your basal ganglia can also again synapse on neurons within the putamen and that can go to your globus pellitus externus from the globus polytus x-terminus it can go to the subthalamus from the subthalamus it can go back to the globus politus internis and then to the ventral anterior nucleus of the thalamus and back up to the cerebral cortex this pathway the other pathway is called the indirect pathway and the indirect pathway is designed to pretty much kind of like slow down dampen the already planned motor movements the last thing that can happen here is you have this structure here called the substantia and it has a lot of dopaminergic neurons that can come over here and basically help to excite or amplify both the direct pathway and indirect pathway okay the whole thing i want you to remember from this is that you have a motor plant coming from your cortex to the basal ganglia they sift through it via the direct indirect modify it in a particular way send it back to the thalamus and the thalamus sends it back to the cerebral cortex now we have the perfect motor movement that we have planned and that we can initiate now what is this area of the cerebral cortex that we primarily send these thalamocortical fibers to that's important to remember this is called the pre motor cortex and if you really want to remember this is broadman area number six all right beautiful beautiful beautiful so ventral ontario nucleus receives input from basal ganglia sends it to the pre-motor cortex involved in initiation and planning of proper motor movement let's move on to the next and last nucleus thank the lord this last nucleus here is called the ventral lateral nucleus what is this one called the ventral lateral nucleus of the thalamus okay so again we already talked about this before let's do this in pink what we have before here's anterior posterior lateral medial right here we have the ventral anterior nucleus so behind it just posterior to it and a little bit lateral you're going to have the ventral lateral nucleus so we have our ventral anterior and ventral lateral nucleus now the ventral lateral nucleus has primarily two types of functions one is it plays a role in coordination so it plays a role in coordination of motor movement so coordination of motor movement and modulation modulation of motor movement particularly again going back to the kind of planning and initiating aspect of it okay so how does that all kind of factor in so again basic takeaway is that the ventral lateral nucleus is involved in coordination and modulation of motor movement there's two inputs to the ventral lateral nucleus the basal ganglia which you already talked about so basically we're not going to go through all the direct and indirect but basically information from the motor cortex comes down to the basal ganglia and sends that information to the ventral lateral nucleus all the things that we need to kind of help to modulate our motor movements right so dampen it or amplify it that's the basic concept we already talked about it above and then from that that ventral lateral nucleus will take all of those different modifications coming from the basal ganglia and send that back up to the motor cortex you know what else is happening here's what's really cool not only is this motor plan going to the basal ganglia to let the basal gang basal ganglia modify it but guess what else it's doing son of a gun is smart it also sends information about a motor plan down to the cerebellum the cerebellum is involved in coordination of movement it's involved in tone it's involved in posture guess what the cerebellum is also receiving things from you know it's receiving information about proprioception what is proprioception it's the position of your muscles your tendons your joints your ligaments all in a three-dimensional space it's receiving all of that information so it knows where our muscles our tendons our joints are in a three-dimensional space then it receives information from the cerebral cortex about the planned motor movement it also receives information from the inner ear you know from our vestibule there's also information that can be sent in to the cerebellum about the inner ear so it receives information based upon our equilibrium so it's receiving information about equilibrium it's receiving information about all the different types of sensations in our three-dimensional space and it receives a pre-planned motor plan a pre uh kind of a pre-designed motor idea it takes all the information about the position of muscles tendons joints takes all the information about our inner ear equilibrium and the motor plant and comes up with just the perfect blueprint for the best type of movement necessary then guess what it does once it's kind of taken all this information that we've received it comes up with the perfect blueprint and sends this information up to the ventral lateral nucleus you know what else it can also do though it can go straight to the ventral lateral nucleus or it can also give fibers that go to the red nucleus and then the red nucleus can send some of that information up to the ventral lateral nucleus you know the specific nucleus that actually is kind of in within the cerebellum that's kind of pretty much sending this information to the thalamus you know what that nucleus is called it's called your dentate nucleus so it's one of those deep cerebellar nuclei it's receiving information for the motor plan receiving proprioception equilibrium sifts through it sends the proper motor plan either straight to the ventrolateral nucleus or to the red nucleus then to the ventrilateral nucleus then that ventral lateral nucleus sends that information up to the cortex what area of the cortex do you say the primary motor cortex and this primary motor cortex is also known as brodman area number four so it's the primary motor cortex or broadman area number four so that's the cool thing about the ventral lateral nucleus it's receiving information about modulation of motor plant from the basal ganglia and motor information from the cerebellum about the proper coordination of movement and sends it back to the cortex so beautiful all right engineers this was a mammoth of a topic and i hope it all made sense in this video where we covered all the different thalamic nuclea all their different connections and functions if it did make sense and you guys did like it please smash that like button comment down in the comment section and please subscribe also down in the description box with links to our facebook our instagram patreon all of those things go check it out again once again big shout out to aim he's the one who basically suggested that we do this video he's also one of our master ninja nerd members if you guys want to also request some videos have some other different types of perks that we have on our youtube page go check out join the subscription and you guys can also request a video for us to make for you guys all right engineers as always we love you we thank you and until next time [Music] you