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BIOL 4315/6315 Neuroscience Tue Th - NEURO Lecture 14 CNS I
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00:01 today's lecture 14 of nurse ons. gonna start talking about structure. Major
00:08 a little bit about the development of C. N. S. And
00:12 parts and functions of the cns and left and the column. You have
00:17 animal brains to scale from rat which only about one plus six centimeters in
00:25 to human to dolphin. And as can see that different animals even dolphin
00:32 are larger and they have very large of down here in the back and
00:38 we thought back about what foreign ologists about the brain and the capabilities of
00:45 brain, they said that it's really on the size of the organ be
00:49 function and its ability. So dolphins be at the top of the food
00:55 in this diagram. Uh And they're much at the top of the food
01:00 and the sea more or less. know some of the smartest animals.
01:04 if you look at the brains that not to scale, you'll see that
01:08 features and certain animals that we discussed the very beginning will have certain anatomical
01:16 . Parts of the brain and anatomy those parts of the brain that occupy
01:23 a bit of a total body mass the brain. So the olfactory bulbs
01:28 rats, relatively to the whole size the brain are much larger And you
01:32 see these much smaller actually olfactory bulbs to pansy. You can barely see
01:38 here relatively to the size of the . And we'll kind of talk about
01:43 of these differences in different parts of brain and how different animals dedicate different
01:50 and amount of the brain for certain that they process. Now. The
01:56 thing to note is wrapped and rabid , the lower order species are not
02:00 sophisticated anatomically, just by looking at surface anatomy. And when you look
02:05 the human surface anatomy, you see lot of salsa and ridges, which
02:09 basically these ridges uh and salsa and this imaginations that go in between the
02:18 , which gives our brains complexity, dimensional complexity to the structure, complexity
02:24 the inter connectivity within this three dimensional , as well as a lot of
02:29 area. And there's three dimensional positioning could be found by neurons along this
02:37 anatomical structure. When we talk about , we always talk about um some
02:44 the terms that we use in such as interior Roscoe, the front
02:49 the tail would be posterior or coddle door. Sol side is on the
02:54 , ventral side is in the You have the brain, the spinal
02:59 , you can see that in rats kind of almost runs in line the
03:04 , cerebellum and spinal cord. In cerebrum cerebellum them and there's almost 90°
03:09 downwards to the spinal cord. The line, The middle is called the
03:15 side. The further away you go the middle, you going more laterally
03:22 describe a lot of the brain stretches nuclei. We actually use these terms
03:29 as anterior dorsal nuclei of so and and lateral posterior dorsal nuclei or so
03:36 so. So a lot of these important than anatomical designations for different parts
03:42 the brand. Now the brain can be cut in different planes. It
03:47 be cut rosco to paddle almost like midline to the periphery. So mid
03:54 cut horizontally, right along the horizon corona. This transverse cross corona cut
04:03 . Now, the way you're anonymous these cuts is that if we know
04:07 this is a corona will cut, say a posterior part of a certain
04:12 of the brain. We use those when we look at them under a
04:17 . Almost like a map. Just we would use the map to locate
04:22 buildings on campus. We would use . Okay, so I'm here in
04:25 structure of the brain next to this and this structure and it helps you
04:29 you recognize uh oh the buildings. when you're looking for something or other
04:32 , a gas station Mcdonald's, you're for your dentist or something like
04:36 Is there the same way we would these clues, interior lateral posterior sagittal
04:43 horizontal cuts in order to look under microscope and find ourselves identifying different parts
04:49 the brain. Uh you can again that there's right and left cerebral hemispheres
04:56 a common theme on the back of brain. you have the cerebellum brainstem
05:00 going into the spinal cord. This a view through, let's say,
05:04 cut. So here you basically separated two hemispheres and you're looking here on
05:08 right side of the brain, the hemisphere, you're looking from the midline
05:13 going that way with the lateral and there's lateralization of brain function. So
05:20 cerebral hemispheres are responsible for different functions the left cerebral hemispheres. When we
05:26 about Broca's area and languages, we focused on the left side of the
05:31 , the left hemisphere. And so are different functions that we call lateralization
05:36 brain function right to left that are parts of the brain, left to
05:42 are responsible for. You have cerebrum hemispheres. When we're talking about processing
05:50 sensory and motor information, it's contra , meaning that if I send a
05:56 command to move my right hand and do this, it's my left motor
06:02 , it's instructing for me to move right hand. But the motor cortex
06:08 gonna have to communicate this information down to the spinal cord. Eventually in
06:14 spinal cord what motor neuron as you , is going to execute this function
06:20 release of the single colon. But code for this pattern that I'm doing
06:25 is coming from my left motor cerebellum which is on the back of
06:30 brain and cerebellum uh serves several but one of the functions is adjustment
06:37 movement and fine tuning of movement that on the lateral side. So once
06:45 contra lateral motor cortex initiates this pattern at the very last minute I want
06:51 change this pattern instead of this into slightly different that I'm doing. That
06:58 now from the IFC lateral from the side cerebellum that we'll be doing this
07:03 switch, so this would be adjustment movement that will discuss further as we
07:09 more about cerebellum. Uh Cerebellum is responsible for procedural memories which procedural memories
07:21 different from semantic memories. When we about the circuits in the hippocampus excited
07:27 an inhibitory circuits. We talked about semantic memory. We said that hippocampus
07:32 involved in processing emotions and also semantic which is facts and names and
07:42 Procedural memory and good example of that how to ride a bicycle. Procedural
07:50 are very hard wired within structures such the cerebellum and that means that if
07:58 once learned how to ride a bicycle you haven't ridden a bicycle for 20
08:05 , you can sit down on that 20 years later and adjustable but for
08:11 , wobble or whatnot and go and a bike just like you did 20
08:16 ago. Now this is a procedural , it's very hard wired, hard
08:22 great semantic and story memory or learning in a way it's not as hard
08:28 great. So try to solve the that you solved five years ago And
08:33 gonna probably spend a lot longer time to solve that equation and your reminders
08:40 you're a specialist and stayed within that . But no you didn't. So
08:45 say for 20 years you didn't do equations and now you go back and
08:49 it. So it's gonna be much task to call that kind of a
08:54 . Yeah, you turn something into memory like for example the equation example
09:00 that become procedural memory. It's a good question. I would say that
09:05 it can become a procedural memory if is very clearly tied to motor output
09:10 motor function. So let's say if have solved that equation and 2000 times
09:17 you solve that equation, you repeated motion, you know, or maybe
09:21 carved it in and you carved it multiple times. That that did help
09:27 recall. The two are definitely Uh There's, we'll see an example
09:32 simple behavior like playing tenants that would a lot of features of motor coordination
09:38 also motivational and memory aspects because that help you potentially in sports like win
09:46 game and motivated to win the That's a very good question. And
09:51 another way that you can think about is that there is talent to be
09:56 in motor coordination and motor skills. patterns don't come from the weights and
10:03 the weights in in the gym. building a muscle. The patterns are
10:09 from the brain, how you're going execute that. Imagine being pole
10:14 you know, how many different things involves doing that exercise and and so
10:20 is hard and grained. You it repeats a lot of times.
10:24 requires repetition to to be hard and , even the motor skills. But
10:29 it's a special talent. The special for athletes that are capable of having
10:35 output from the spinal cord execute this patterns. So, you know,
10:41 has to be here and here in for you to to to do these
10:45 complex athletic uh schemes and performances. , yeah, it's definitely with motion
11:00 movement control and adjustment of movement. , brain stem is where you will
11:08 in the brainstem, a lot of connections between passing through here area that's
11:14 , We'll talk about it and bracelet responsible for vital body functions, breathing
11:20 , control of body temperature. Uh there are nuclei collections of the cells
11:26 the brainstem and we also know that are nuclei collections of the celery brain
11:31 from neural transmission that they produce special such as norepinephrine or serotonin. And
11:39 nuclei also, there are collections of cells that are responsible and coordinating complex
11:47 such as breathing uh and and There is of course peripheral nervous system
11:56 we mentioned. We talked about how can control motor and sensor information flux
12:05 into the spinal cord in the peripheral system. The somatic. You have
12:11 from skins, joints and muscles that into the door so the gang then
12:15 have the output from the motor neurons onto the muscles. It is also
12:21 peripheral nervous system that is a visceral autonomy. And there you're talking about
12:29 organs, blood vessels and glands that be innovated with different nerve endings.
12:35 what's really interesting is emergent in the of biology and neuroscience is this concept
12:43 microbiome that our guts. That what ingest and the probiotics in the bacteria
12:49 we carry in our guts a very they have very complex genetic material more
12:56 material than we have in our own or sitting in our guts that are
13:01 by these microorganisms. And these microorganisms influence what is called Mesen Terek nervous
13:09 and this mess enteric nervous system which peripheral nervous system and nerve endings around
13:14 lining of the gut. In the system is potentially ask complex in its
13:21 and connectivity as the cerebral cortex that talking about. And so there's a
13:27 to be discovered there. And recent shows that imbalance in the microbiome metabolites
13:34 metabolites that imbalanced microbiome producers can actually the function of the C.
13:41 S. And could even be implicated some of the neurological disorders. So
13:47 a very interesting field of study that's . But if you hear something about
13:52 or the nervous system of the gut know the gut brain access. It's
13:58 because there's so much interaction. I encourage you to attend to talk or
14:03 to talk or um learn a little more on your own. The brain
14:09 protected. So besides having this thick . The brain has three types of
14:15 . The most surface one closest to scalp is dura mater. It's also
14:19 thickest one. It's the hard You cannot just poke through it.
14:23 have to cut through it with a or nine below. If you have
14:27 space of dural space underneath the dura is filled with arugula membrane. It's
14:33 of a spider like thingies that has little bit of movement and can have
14:42 uh dura mater come closer a little . It needed under pressure. And
14:47 the very surface of the brain tissue have P. M. On it
14:52 is the gentle mother that supplies the and protects the brain. And so
14:58 the help of these three types of we have significant protection of the
15:05 We have fluid fluid like gel like here in between Iraq annoyed spaces would
15:11 a little bit of cushion. So is a impact on to the brain
15:16 the brain moves inside the skull with cushion And then you also have these
15:21 blood vessels in the subdural space and blood vessels and then penetrate within and
15:27 the cerebral cortex and form the micro that would penetrate throughout different brain
15:34 So when we talked about Brain Triple , I wrote down here. Subdural
15:41 , entrepreneur nation. So there is rupture of the blood vessel. That
15:45 be a stroke. It could be aneurysm. It could be some sort
15:49 a strange injury. Tooth could be from the outside the structure of the
15:53 vessel. What can happen and when blood vessels ruptures, you have coagulants
15:58 your blood and the coagulants try to the bleed by thickening your blood and
16:05 it from coming out of the blood . So now this rupture is uh
16:11 significant and there will be accumulation of blood clot like material and potentially even
16:18 leaking fresh blood forming what is called hematoma. And those hematomas can be
16:25 severely. You can have him a just in the pro periphery, on
16:30 , on your arms and legs. you have a significant injury that could
16:33 a rupture of the blood vessel and could have an accumulation off the blood
16:38 a hematoma under your skin or muscle or where not wherever you have the
16:45 vessel rupture. So if you think tre pronation is the only way to
16:50 up the subdural hematoma would be to up the window and the skull,
16:55 opened up the PM. Model the mater and then clean out that area
17:01 you would with a regular one. you had that problem that re occurred
17:06 it didn't work the first time and know the bleed continued then you may
17:10 to go back and reopen that same . And so brain trepidations was repeated
17:16 the same locations. It's also potentially could have problems in two or three
17:21 areas of the brain, the similar . And so when we talked about
17:25 pronation, who said that there were multiple locations on the skull where these
17:31 entries into the brain tissue were So that's something to think about.
17:36 you think about subdural hematomas and brain pronation. You have the whole ventricular
17:42 where you have the production of cerebrospinal and the court plexus here have the
17:48 of the right ventricle, still lateral . You have the circulation of the
17:53 spinal fluid going into the subarachnoid And uh the super spinal fluid gets
18:01 and gets recirculated and it surrounds cns titian and goes all the way to
18:07 spinal cord through the spinal canal. so this also serves as another kind
18:14 a cushion with super spinal fluid. brain is surrounded by this fluid is
18:19 like environment section of the brain that to say that the of the brain
18:28 for memory. Memory memories for that . Yeah. So if if if
18:34 hematoma would not be cleaned up in particular part of the brain can start
18:40 injury locally around the area and that impact whatever that part of the brain
18:47 responsible for. So it could be the Broca's area then it would be
18:54 aphasia. If you had it, know, for example vernick asse area
18:58 that would more maybe be a language where you cannot understand or hear and
19:06 things to understand very well if it's clean or medical attention to it will
19:13 to other areas you know. But may happen is that you may start
19:19 a process of inflammation and neural degeneration and that may lead to scarring by
19:27 cells. Glial scarring and that could of generate cascade of events around the
19:34 that may start affecting the adjacent circuits well, you know questions So once
19:43 produce the cerebral spinal fluid there's a amount of cerebrospinal fluid that gets produced
19:48 certain amount that gets drained. And you have this amount of production of
19:56 fluid drainage of cerebrospinal fluid. And happens is that there's a condition during
20:02 development called hydrocephalus in that condition can just as developmental condition or it can
20:12 a mechanical induced component. So if baby is shaken for a long time
20:20 the baby injured the head. It lead to hydrocephalus which produces abnormal amounts
20:26 cerebral spinal fluid and it may also impaired drainage system. The lymphatic system
20:33 the cerebrospinal fluid to and the interesting then is then the only way to
20:39 this. Since this ventricles would end and they would start pushing on the
20:44 tissue, the skulls are soft, would start pushing on the skulls and
20:49 cause these abnormally large head shapes, shapes or alien head shapes is whatever
20:56 understanding is up of the alien head and the treatment we've been starting it
21:03 into the lateral ventricle through a hole the skull and draining that fluid.
21:08 if it's in a child and it's chronic problem that's persistent, It doesn't
21:13 away then draining that fluid and leaving space for a child to grow so
21:20 you can continue draining into the Menial cavity, space brain trepidations.
21:26 , that's the only way that you get again to draining into the
21:30 So maybe when we see actually evidence these prehistoric skulls that were Children that
21:38 brain to Oprah Nations, it is probably related to conditions like this.
21:44 , for the so that's the top of the brain tissue, is that
21:50 scone it's right underneath the skull and the first men injuries right on the
21:56 of the brain brain tissue and above the and the other ones are.
22:08 there are many injuries. Yeah. they're not neurons or glia. No
22:17 now we're gonna spend a little bit time talking about how this nervous system
22:22 , how it comes to buy you of all have three major tissues and
22:31 measured ERM and ectodermal during the development gives birth the lining of internal
22:37 Services measured ERM skeleton bones and muscles actor. Durmus nervous system and
22:46 So at the very early stages these cells can either become neurons or they
22:51 become skin cells. In other words can differentiate into different types of
22:57 And at the beginning you have neural in the neural plate is comprised of
23:06 tissues that you're seeing here is the ERM. Yeah and you have measured
23:14 and then this plate curves and forms neural group and you have a neural
23:24 and then that neural group and neural . Close up in form neural tube
23:30 is called no relation. And you see that this is now the neural
23:36 in green okay from the neural plate you have the somalians here and the
23:45 has become the vertebral column and skeletal here. This is our neural
23:52 So we're going to pursue this for development of the C. N.
23:58 . And this is a picture of new relation process and the proper formation
24:05 the neural to I don't want to out the fact that this is a
24:10 self assembled system just like the bodies when the two cells meet together and
24:19 sperm and the egg from that moment there is perfect environment hopefully in the
24:27 . But there's a self assembly and . Nobody's putting the cells together and
24:33 them mechanically. So the brain that complex as the brain is itself assembles
24:40 well and there is little uh So it's a pretty robust code for
24:47 assembly, meaning that one in 1000 end up with developmental one in 2000
24:55 developmental conditions that are particularly related to assembly and early development of this new
25:03 processes in the brain. But it's complex. You know, something from
25:07 plate becomes a tube and then you'll differentiates into structures that we've already
25:12 We have in the brain, this the roster apart, this is the
25:17 part. This is normal development. you have problems with the roster development
25:24 this process of folding into neural tube may end up in the condition that
25:29 unsustainable, unsettling. So a lack cerebral, basically if the impact is
25:39 towards the caudal parts of the spinal , one of these rare developmental abnormalities
25:45 can happen that I'm talking about despite very robust code, rare ones that
25:50 happened in the formation of spina bifida spina bifida is essentially because the folding
25:57 be abnormal along the neural to this misfold the spinal cord and the spinal
26:04 may actually stick out outside of the column. And so this is something
26:10 can be treated medically uh during early . Now let's follow what happens further
26:21 this neural tube. You have the of differentiation which means that you have
26:28 and more complexity, anatomical complexity that happening more of this cellular self assembly
26:35 I'm talking about. The roster part the brain is now called President
26:41 forebrain right below it. You have or lessen cephalon and the green part
26:49 wrong. But cephalon, hind brain other part would be going into the
26:53 cord. Now forebrain further differentiates. first it's the primary vesicles are called
27:00 brain vesicles. And then there's blue cephalon differentiates into your talent. The
27:07 vesicles, dyin, cephalon. And has here the outgrowth of the optic
27:15 , the optic cup and the optic . And here the edge of the
27:21 cup which will be the retina. retina is a part of the central
27:27 system. So if you study if you're an optometry and you have
27:32 study retina, you're also a Other parts of the eyeball are not
27:40 related to neuroscience and reflective movements of eyeball is related to cranial nerves.
27:46 related to concepts of neuroscience. And learned the cranial nerves at least by
27:53 I believe that are important for us the next lecture. And I often
27:59 responses from my students that are later medical Dental school. Uh talk school
28:04 optometry. Uh the nursing school, cats takers uh medical schools. That
28:15 thank me for like, oh I'm glad you're talking to us about
28:19 This subject matters cranial nerves. So also learn that next legend.
28:25 mid brain and hind brain and there's differentiation. You can see that telling
28:31 forms the two cerebral hemispheres. You the dying cephalon here in the midbrain
28:36 the hind brain you can see that stage with differentiation. There's more and
28:42 anatomical complexity in these structures and now midbrain becomes a collection of these four
28:49 . Some of my favorite ones called quadra gemini. So again, when
28:54 learning something and in anatomy you have know where you are, medial,
28:59 , posterior, anterior and so superior, inferior. And then it's
29:05 good to think about the language. does it mean? So if I
29:08 corpora quadra, gemini, corpora corporate . Maybe in some languages, corporate
29:18 , whatever language you can associated with best corporate quadrille Quattro. Now you
29:26 cars, that's a quadra on them probably means four by four or Something
29:30 do with four quadra for Quadra Gemini bodies. So basically a collection of
29:39 bodies and we'll talk about them because involved in processing special aspects of
29:46 And here. So we'll come back talk about the next lecture telling cephalon
29:53 you see here. Diane cephalon becomes on top and hypothalamus underneath telling cephalon
30:01 the cerebral cortex and you have the telling cephalon that also becomes parts of
30:06 cerebral cortex. Then you have lateral here, the third ventricle going in
30:14 callosum which is the structure that interconnected hemisphere. So if the command goes
30:20 of the right hemisphere or something that processed in the right hemisphere, that
30:25 hemisphere dominant aspect of whatever processing is is going to be communicated through corpus
30:33 to the opposite side. And this a major fiber bundle that basically inter
30:40 the two cortical hemispheres, the left the right cortical hemisphere from Solomon issue
30:47 have a lot of connections and axons exit out and going through the cortex
30:52 from the cortex you will have a of connections running back into the
30:57 And so you will have the parents these white fibers and these connections and
31:04 bundles of connectivity and referred to as capsule. You know. So we
31:11 at this brain ship enterprise, we the long long yellow is the spinal
31:21 have the cortex all of these structures come out and differentiate olfactory bulbs from
31:28 . You have thalamus hypothalamus from hind you have text um which maybe some
31:35 you would know this word the roof . Um at the back of your
31:40 the roof take momentum is in the side cerebellum comes from uh hind brain
31:49 . You know I'm saying this is mid brain, this is from high
31:52 cerebellum, pons and medulla of long . And then the yellow is the
31:58 cord have the ventricles and will be the staff from lotto to third to
32:04 the way, fourth ventricle all the into the spinal cord canal. There
32:14 go. The south side of the . This is now you have the
32:24 mature formation of the brain with the system of three dimensions depicted how it
32:30 be actually sitting within the central nervous and going into the spinal canal here
32:37 south side are the grooves, the the ridges. We believe that cortex
32:44 reasoning the seat of reasoning and So maybe you can survive with brain
32:50 because you have breathing heart rate and things but you probably need cortex for
32:56 and cognition. And so we know there is damage to cortex and connectivity
33:02 the cortex from other structures that are information to the cortex, we do
33:07 lose these aspects. Uh These functions I'm talking about. There will be
33:15 a few labeling questions on this exam most of them will come from labeling
33:21 brain structures rather than neurotransmitters and visual components that will study in this section
33:29 well and when you are labeling I don't always use the exact same
33:37 . I use in class and I sometimes use images in a different
33:43 So the best way for you to it and we'll even see it later
33:47 the course is that just to learn in three dimensions. So you can
33:51 these structures very well and you can the structure independently of blue,
33:56 yellow color, the size and on presentation. Okay. But just to
34:02 you, we have the frontal lobe the central southeast that separates from the
34:07 lobe, the temporal lobe here you the occipital lobe cerebellum. These are
34:12 lateral ventricles and the ventricular system that's . There's quite a few similarities,
34:18 quite a few differences. There's some things that repeat basic structures that you
34:23 in a rat and a human. once again there are structures that take
34:28 a lot of brain mass and brain like olfactory bulbs in rodents and tiny
34:36 evolves that we find in humans. this will be another theme of primary
34:41 processing that comes from the outside The other thing is there is redundancy
34:49 in the cortex which you find only mammals in the structure of the
34:55 in the dominant subtypes of cells such our famous parameter cells that we talked
35:02 in hippocampus. But you will find cells and neocortex and find them an
35:07 neocortex. Look at these huge olfactory that's all that's all the gators do
35:13 they smell the search for food. means that out of this entire body
35:19 , almost half of it, almost of what alligator does or half of
35:26 brain mass is dedicated to smelling to the food drilling to survive. But
35:32 can take a plug of the alligator or plug from the rodent cortex.
35:38 you will find the parameter cells and . You'll find some of the canonical
35:47 and canonical circuits that we talked Excitation and inhibition, inhibition, inhibition
35:52 excitation across different species as well. This is another example of staying with
36:03 stain. If you remember, missile will stain all the south that it's
36:09 to. When we look in the . If you look at the missile
36:15 , if you guys don't mind, gonna sit down for a minute.
36:17 take a little break from standing. And what you see here is a
36:25 stain. And as you can see missile stain clearly shows some very dense
36:32 of cells. And so the more cortex was studied and stained using different
36:39 . And here you have a collection stains in this diagram. First of
36:43 you have the Golgi stain. If remember Golgi stain will only stain the
36:51 very small subset a few percentages of of the neurons that it's exposed
36:57 So it will reveal the precise anatomy the processes. This will stain will
37:03 all of the cells. So it reveal the side or architecture the densities
37:10 sizes of these cells, their orientations properties and such. This is a
37:18 stain that we haven't looked at as stain. Weigert stain is specific to
37:24 and it was very clear that if looked across these different stains you would
37:30 that what's happening in the new york is that you have some sort of
37:34 layers structure which is referred to as . And you have very clearly these
37:44 dendrites and these axons that are running up and down through these layers Given
37:54 also to call them the structure. you can think of these columns or
38:02 columns that come in different sizes. very small. We're talking about
38:09 micrometers in diameter that are like neurons very similar response properties. And one
38:18 these columns can be viewed as a processing network, almost like a processing
38:26 . And so cells that will be visual information and similar type of visual
38:32 will have a micro column. Next there's gonna be a micro column that
38:36 very similar type of visual information, say color. Next to it.
38:41 micro column. So you'll have parallel of information in general. We have
38:47 processing of information in the brain because example we have two years, two
38:55 , one mouth but two eyes. , two nostrils. Like there's a
39:03 of parallel processing on this gross anatomical and then on the micro or microscopic
39:11 you have these micro columns that are gonna be parallel processing. One column
39:17 another will be in parallel processing very and sometimes the same type of
39:25 pardon me. So what you have the six layers is a pretty precise
39:33 of inputs. Where are the The inputs into the cortex come
39:38 Where they come from below the Sub cortical e from places like don
39:46 like talons, they also come from parts of the cortex. So if
39:52 in in some place in the parietal that cortex may receive information from other
39:59 of cortex. From occipital cortex from cortex. Structure depends on function and
40:09 depends on structure. The two are inter intermingled interrelated, interdependent ble What
40:17 the structure of these neurons will determine connectivity they can form with each other
40:21 will determine their function. However, there is no activity there's no function
40:28 this connectivity then that can change a . So the activity can change the
40:36 . Therefore the structure is also dependent the function and levels of activity just
40:43 you can take different plugs of the from the alligator and from the
40:48 You can also uh take little plugs the neocortex from different parts of the
40:58 from the prefrontal cortex from primary motor here from parietal association area from primary
41:07 cortex here in the occipital lobe and will all show the sixth layer
41:14 They will have similarities. They will parameter cells that have excited to inhibit
41:19 networks. The diversity in the subtypes cells just like in hippocampus will come
41:24 the inhibitory cell subtypes. You can the difference here is that the thickness
41:30 that new cortical matter six layer structure so it's a little bit thinner in
41:36 primary visual cortex and it's a little thicker in the parietal association cortex.
41:46 no similar representation, similar and adamant you see across and you have the
41:56 architect tonic methods. And of course interesting is that nestle stain can also
42:03 between glia and neurons so it cannot the exact. It's not a very
42:09 method of distinguishing gloomy innards, but can use it and you can look
42:14 it more of a structurally based around selma because you don't stay in
42:19 There's a great method in developing all the side architect tonic descriptions where structure
42:30 function basically. And he was correct many ways where a certain structure in
42:36 17, the primary visual cortex here the very back of the brain meant
42:40 certain function and area 18 which is had different side architect tonic structure actually
42:48 responsible for a different function. So was correct in many ways in that
42:56 . Now this is an interesting subject and this diagram depicts primary sensory processing
43:10 . This is the primary sensory processing in red. In rats for visual
43:20 and it is much smaller, relatively the size of the brain, This
43:26 area relatively to the size of the and a cat. And then it's
43:31 small. The primary visual area, really small in humans. So if
43:39 for enologist you would say this is bigger muscle here in rats. So
43:44 have better vision than humans, but not the case. Primary sensor information
43:52 areas are dedicated to processing raw primary information or all of the information that
44:01 processed here in the primary information is do I see? This would be
44:08 analogy comparing what do I see? do I hear? What do I
44:15 here to censor democracy system? Uh these primary areas, the information goes
44:24 secondary areas, tertiary, ordinary And from this area here, the
44:33 of what I see Hierarchically in the visual cortical area 18 becomes more
44:42 It gains more color literally, and also gains certain other aspects of visual
44:50 processing that does not happen in the area of information processing. And
44:57 you have association areas and those association and primate brains, especially in humans
45:06 areas that are capable of taking visual because once that visual information is no
45:14 what I see, what becomes with individual information in your head is how
45:21 I interpret what I see and to that, you're gonna have to potentially
45:30 other sensory cues? How do I a naked person standing on the street
45:38 a naked person in the museum on painting? Very different interpretations of almost
45:47 same thing in a way. But you involve other sensory and other
45:55 environmental cues around you. So what listening to the best way you're learning
46:01 you're attending the lectures, you're doing things, you're associating what you're listening
46:09 when I talk, you're looking at and maybe even writing down notes.
46:15 really great, because there's a three and the motor activity of writing down
46:21 and checking something that's involved, that's going to help you learn the
46:27 So the association areas are gonna take sensory primary information that become hierarchically more
46:36 and secondary tertiary ordinary areas. And going to co join these different sensory
46:42 , vision, hearing, taste, , touch, and interpret it in
46:48 certain way. Association areas will then pretty large areas and a lot of
46:55 human brain will be dedicated to associating senses. We also learn things the
47:02 when we associate them with something Do not just one thing, not
47:07 want sensory or motor action. So areas will be huge in primate brains
47:15 there isn't much space left in the here for associating things. So most
47:22 what the lower order species are dominated is what I see, what I
47:27 , but not how do I interpret touch or smell? How do I
47:32 what I see? And that's what do. And that's where the magic
47:38 . The magic happens in the association in our brains. And we also
47:44 individuality and differences in brain connectivity. we clearly very clearly have differences in
47:54 and interpretation of even the factual things happen. You can have a fact
48:01 in front of two people and they walk away and they will say that
48:05 person this happened and another person will it didn't happen and how did this
48:12 ? So there's some sort of a interpretation. It's a different encoding different
48:18 , but this happens quite often. know, it doesn't it doesn't even
48:22 to be about politics, but uh anything in life to, people could
48:27 away and people could argue over stuff happened. One will say no,
48:31 didn't say that. Yes, you it. No, I didn't say
48:34 . Yes, we said let's play recording. Yes. You said it
48:37 the person who said I did or may say like no, that's not
48:41 , I didn't say, you but we do have all of these
48:46 individualistic interpretations of the world and having large areas of the brain that are
48:54 to association is what gives us the to be individuals to interpret things
49:01 to be creative, to be capable metaphorical thinking. Where the other lower
49:09 species may not even have that kind ability of metaphorical anna logical, logical
49:18 and and and such. Okay, spinal cord is divided into major areas
49:26 lumber, thorax, stick, sacral, the very bottom lumber,
49:32 back, lumberjack, thoracic, your , cervical is in the neck and
49:38 it goes into brainstem which is middle long gotta ponds. Now sir velo
49:43 the back attached from the pons and going into the dying cephalon which is
49:49 and hypothalamus surrounded by basil ganglia and cerebral hemispheres. So spinal cord as
49:57 know, receives and processes sensor information skin joins muscles of limb and
50:04 Everything basically below the neck will go the spinal cord, everything in the
50:10 part of the neck. Here from brain stem in everything surrounded by the
50:15 will be processed by the cranial nerves they're located in the brain and the
50:21 cord controls the movement of limbs and . So I give the command.
50:26 the command control is by motor neurons are coming from spinal cord to
50:31 This hand. Brain stem is where have sensor information from the muscles of
50:36 head. So everything from the head of the head muscles, sensor information
50:43 of the face and such is processed brainstem by cranial nerve nuclei that it
50:48 be both or either it can either sensory and motor or just sensory or
50:54 motor. So these nuclear will send the nerve endings throughout the face and
50:59 head that will either sense or motor different muscles of the head and neck
51:05 perform both functions. You also have senses that you can find here nuclear
51:12 responsible for hearing, balanced taste and reflexive, visual information, processing,
51:21 oblon gata is responsible for vital economic , breathing, heart rate and digestion
51:29 . You have motor information from cerebrum and cerebellum. They will both
51:36 communicating with each other. A lot the central connectivity is happening from through
51:43 cerebellum is controlling the force and range movement. It's responsible for learning motor
51:51 , procedural memory and it is attached the brain stem through these structures called
51:59 dunkel. So we will look at in the next lecture and a few
52:02 from now mid brain you have sensory motor function information including eye movement,
52:10 , visual and auditory reflexes. In midbrain that we're talking about that I
52:16 mentioning the structure Quadra quadra gemma, quadra gemini that is there dan cephalon
52:23 is thalamus, hypothalamus thalamus is involved information all of the information that goes
52:30 the cortex goes through the thalamus. of the information exits out of the
52:34 goes through the thalamus, hypothalamus is for autonomic involuntary bodily functions. Hypothalamus
52:45 talk about in greater detail in the slide. It's also this hypothalamic structure
52:51 a part of the kind of an gland and hormonal systems and can influence
52:58 function. So this is hypothalamus is of what you would call the neuro
53:04 system because hypothalamus can influence hormone, hormone release of other hormones such as
53:11 growth hormones. The hypothalamus also has thin blood barrier. So I have
53:19 follow those serves as a gauge for and process temperature information will come back
53:25 talk about the next slide and cerebral . We talk about cerebral cortex and
53:30 we may mention three major nuclear basil which is shown their basal ganglia where
53:37 lot of motor uh coordination and complex of motor commands, whatever the complex
53:48 maybe for you, it could be something down on earth could be hitting
53:53 ball with the racket but these complex would be initiated and stored quite often
54:06 basal ganglia, hippocampus. The structure we already talked about is involved in
54:13 information processing because it's a part of limbic system but it's also semantic memory
54:21 off this memory, semantic memory and of that memory but not storage the
54:27 of memory is widely distributed throughout the in different parts of the cortex and
54:35 will recall and contact these different parts the cortex in order to recall complex
54:41 of memories, amygdala, its emotional , it's also involved in homeostasis and
54:52 also a fear center. So it the information and these three special nuclear
54:58 the way that we mentioned here, talk about some of them a little
55:03 more. Let's look at this the tennis ball and a is flying
55:08 you so most likely in a think the parts of the brain that would
55:13 engaged and this is somewhat simple behavior hitting the ball back, but you
55:18 put it within the context and you put it within a story also to
55:26 this better ball is flying at What are you going to be
55:29 focusing on the ball, You're watching ball right? So your occipital lobe
55:34 gonna be really heavily involved. but at the same time there's going
55:39 be some sort of a planning going as the ball is approaching. Am
55:44 gonna have to fall back to the of the court? Am I gonna
55:48 to come to the net closer to to raise my racket. Do I
55:52 to do forward back swing behind the ? So you also have the amygdala
56:01 is emotional center and whom the ecstatic . So that's important, you
56:06 keep up the good spirits, you , people are training for you to
56:11 to hit a good shot. So also involved in all of these parts
56:16 the brain get activated. Now the , the ball is in your
56:22 as they say, the ball is your court. Now you're of course
56:27 to be looking at the ball, now the information and the parts of
56:32 brain that activated and hitting the ball going to shift a lot of that
56:37 from just looking at the ball to hitting the ball. And so you
56:41 have basil ganglia where you have motor initiation and recall the motor pattern is
56:47 gonna step back and swing forward to this ball back. The command the
56:54 talks to the motor cortex, the cortex as command from brain to muscles
57:00 motor cortex and commandment to the spinal and spinal cord, motor neurons execute
57:07 what the motor cortex told it to their balance besides the procedural memory.
57:13 this balance is also responsible for appropriate , appropriate exception, which is your
57:21 of your body muscles and joints with to yourself, gravity in the outside
57:29 , and the objects that are around . Okay, so you're not hitting
57:33 net, so you're hitting, stopping racket right before the net, appropriate
57:37 understanding and fine tuning. So just you thought you're gonna do the forward
57:44 swing, what happens is you're playing on the clay court and the tennis
57:49 hit a random stone on the clay and shifted its direction. Got Ben
57:55 this way. Now if you don't tune and adjust this initiated command of
58:01 swing and maybe turn around and do back and you're toast. So that's
58:07 Sara bello comes in. A lot councils referred to as middle management,
58:11 account for basically fine tuning off the steps in these motor commands and racquetball
58:18 a good sport to think about it uh once you initiate these patterns and
58:24 behavior, many adjustments can be made the way. And racquetball is a
58:30 example because the ball is rubber, it bounces off the wall differently depending
58:36 the spin, sometimes can bounce fast sometimes can almost drop dead off the
58:41 , you also surrounded by the so the ball can bounce off the
58:46 and the walls and there's a lot last minute adjustments and racquetball at the
58:51 level that have to be done and be done in order to succeed at
58:55 game. So hippocampus, remember I the game point ball, it's part
59:02 memory, semantic memory, putting it the context of the story, I
59:06 so great, I was a it's part of the motivation as part
59:11 the memory to to succeed in the . So here's another representation of the
59:18 brain structures but in a different A little bit more information, but
59:25 are the famous areas, the primary of visual Cortex is area 17.
59:30 . Area 18 tertiary will be area . You can see that within the
59:36 motor cortex. You have also supplementary cortex in front you have division of
59:42 motor cortex in different areas. For you have division of somatic sensory cortex
59:48 areas 123 and one I 12 and on. So there's even more complexity
59:56 and I believe that yeah this is is going to be the last slide
60:02 I'm going to cover. I'm gonna to do it a little faster because
60:06 want to finish today at around 12 if I can. So I'll spend
60:13 five minutes talking about the slide and I'm gonna end the lecture. I
60:16 to rush off to the other side campus uh to my office thalamus is
60:23 here and thalamus is is Stalin. is a collection of different nuclei.
60:30 for example there's a collection of cells lateral nucleus of the thalamus or
60:36 G. M. That is dedicated the visual information processing information from the
60:42 is going to come into the It's going to go into the lateral
60:47 of the thalamus And from there it going to project into the primary area
60:53 of the visual cortex in the occipital . All the way from here is
60:57 project in the back from that internal projections from Fallon. Listen to the
61:02 . So if you're talking about auditory auditory information is going to come into
61:07 air is going to go to the ridiculous nucleus and from there eventually it's
61:11 find its way into the primary auditory into the in the temporal loan.
61:17 a matter of sensor information from the cord is gonna get carried by dorsal
61:23 nuclei. The spinal cord is going project into the nucleus called ventral posterior
61:29 nucleus. So somebody told you posterior lateral versus ventral posterior media.
61:36 you know where medial and lateral is may be able to identify media versus
61:41 nuclear but all of this amount of information is gonna come in from the
61:46 cord into the ventral posterior lateral nucleus from there is going to get into
61:50 amount of sensory cortex. Primary somatosensory areas. S. one. So
61:57 is thomas thomas is a collection of for a long time. It's thought
62:02 be as a relay station. So from retina going to L.
62:07 M. Pass the information it's really to cortex. Occipital lobe connected related
62:15 But it turns out that there is to inhibitor activity in the lateral
62:21 In fact when I showed you the and I said I stimulated the nerves
62:25 I saw the E. P. . P. Followed by gateway
62:28 P. S. P. And . D. I. P.
62:30 . P. That was the response lateral nucleus nucleus. So there is
62:34 whole excited or inhibitor circuit these nuclei they're not they're not just passive relay
62:42 but they're gating and modulating the signals are passing into the retina. Also
62:49 that information to cortex by modulating it then they also get inputs back from
62:55 . So they play a very important in regulating and modulating the amount of
63:01 information that is processed and eventually reaches primary visual cortex of primary auditory cortex
63:10 these nuclear. Now the whole follow and these nuclear will contain excited to
63:18 their sales and service the whole This is surrounded by the sheep that
63:23 called the Islamic particular nucleus. Islamic formation because it's not really like one
63:33 nucleus. Rather it's 23 layer like or sheet that envelopes the entire columnist
63:40 has a very strong inhibitory effect. a communication between their attacks and communication
63:46 colonists and this particular atomic nucleus. very interesting and pretty complex structure.
63:53 there's a significant amount of information processing , gaining modulation inhibition. Excitation boosting
64:03 excitation uh toning down the sensory input inhibition that happens at the level of
64:09 thalamus before it even reaches the primary say auditory or primary visual cortical
64:16 Hypothalamus it's autonomic involuntary bodily functions under glands and hormones and visceral functions.
64:25 temperature appetite, water intake, sexual , lactation, slow growth. There's
64:32 redundancy and functions so there's gonna be parts of the brain and other neurotransmitters
64:38 are involved in regulating such complex behaviors sexual activity. For example, water
64:45 . Uh But hypothalamus is a great for the temperature. It has a
64:50 loose blood brain barrier so it can of a measure the temperature because it
64:56 a loose blood brain barrier can sense well what's in the blood. So
64:59 there's something toxic in the blood, is going to react it very strong
65:04 above other parts of the brain, is also involved in the HP.
65:11 . Access which you may have Where H. Is hypothalamus.
65:17 Is the pituitary gland and a is hypothalamic pituitary adrenal axis which is the
65:26 axis and the major system for control the stress hormone cortisol. So hypothalamus
65:35 involved essentially in control of the cycling the cortisol And then what you call
65:41 stress response off the body. Now you will learn when you study cranial
65:47 and the visual system is the optic is a cranial nerve. Two and
65:52 is a left optic nerve and the optic nerve. You have to retinas
65:57 which these optic nerves are going to out and one component the nasal component
66:04 the two optic nerves is going to over through an area that is referred
66:08 as optic eye ASM. Okay, this is the optic eye ASM and
66:14 near the optic chaos and there's a cat asthmatic nucleus which is also part
66:18 this Don cephalon uh structure and super nucleus is a circadian body clock.
66:27 regulator. And it regulates and engages communicates to other parts of the brain
66:33 the daylight and ambient lights. In morning, it starts producing certain transcription
66:39 that helps your brain circuits awaken and awake and when the lights go down
66:46 artificial lights kick in and darkness sets outside. It's stimulates the other subset
66:53 certain description factors that makes you sleepy regulate your sleep. Wake cycle,
67:01 cycle or what we call the circadian or circadian clock, you can adjust
67:06 circadian rhythm and circadian clock. Yesterday said that if you fly far
67:13 if you go from, you know uh to Houston there is no time
67:20 . But if you go from Louisiana florida, there's one hour time difference
67:24 your body clock is not really going notice it that much. Your pattern
67:29 being awake and asleep is not going change much. In fact, if
67:32 fly from east Coast to west you will find that there's already a
67:36 in this three hour change. But you fly where there are time zones
67:41 by more than five or six hours some instances 8, 10, 12
67:47 hour difference. There can be a adjustments at that time clock. So
67:52 what we call jet lag is that jet left new york and it landed
67:58 Dubai, but your clock is still new york, so you're still living
68:03 you were in new york and Dubai of being asleep, it's in the
68:07 of the day and you have to deal with it. And so it
68:12 time to adjust that clock and experience are better jet lag, you can
68:17 that clock as they say, the clock within a day or two,
68:23 or people that have difficulty actually adjusting different time zones. You can be
68:27 entire trip. So by the time turned your clock, you got to
68:30 home, vacation is over or visiting or whatnot. So super charismatic
68:36 pretty strong in agreement there and how regulates our dead lights cycle. I
68:41 most of us are asleep at this third shift, people work at
68:46 and people constantly have very difficult time working at night because no matter how
68:50 you force yourself there outside cues, , artificial lights that signal constantly to
68:57 circadian uh nuclear super mad nucleus. adjust to a lot of industrial accidents
69:05 they happen, they typically happen in third shift, nighttime, early morning
69:11 , nuclear accident, nuclear accidents. like factory big accidents that may
69:17 Alright, I ran over a little of time. Thank you for being
69:21 and I'm gonna stop here, I'll everyone on thursday and I'll release the
69:25 by
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