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00:02 last lecture we started talking about the of the central nervous system and we

00:08 the concept of new relation from the primordial tissues uh under Massoud ERM extra

00:18 . We talked about how this neural folds and neural to formation if it

00:26 that the caudal parts uh this section here the neural tubes, it can

00:35 a condition that is called spina abnormal neural ation of normal folding of

00:44 tube can result in a spin of if it is on the coral side

00:50 in very very rare cases and stuff , which would be the rostrum part

00:57 the new relation. Of course it's it's a fatal developmental condition. Again

01:03 quite rare as we talked about. developmental malformations are quite rare in humans

01:10 the structure is pretty complex and it about from the President cephalon. Mesen

01:16 , ramblin cephalon which differentiates into brilliant into telling cephalon. Diane cephalon

01:23 the vesicles and mesen cephalon, a in hind brain further differentiates and we

01:30 about how from the talon stuff along uh tell anencephalic or to tell encephalitis

01:39 the ride become the left and right that are interconnected with the corpus callosum

01:47 diane cephalon is comprised of the thalamus hypothalamus and there is strong interconnections through

01:54 internal capsule between the thalamus and cortex cortical alarming communication as well. So

02:02 major parts of this brain ship, rostrum was telling cephalon dan cephalon is

02:07 thalamus. It's all part of the . Mesen cephalon is the membrane Rambert

02:14 , hind brain. Mesen cephalon uh differentiates into detect them and take

02:22 The roman cephalon differentiates into cerebellum and and medulla oblon gata. And finally

02:31 have a spinal cord. We discussed ventricular structure in the brain where you

02:36 the two lateral ventricles, the third fourth ventricle and to the spinal canal

02:43 the spinal cord. If we look the structure across different species and across

02:50 cortical areas in those species can take little plug from the alligator brain,

02:55 little plug off the rat cortex you'll similar structure and you will see similar

03:04 layer structure as well. And you'll some of these similarities even in

03:10 So let's talk about new york cortex cortical organization overall and how we basically

03:19 the cells. Okay, so as recall we had two types of stain

03:25 had the golgi stain which picked up of the processes and we have the

03:29 stain which steam for all of the . It was really good for cider

03:34 studies and so in the cortical organization you have in the cortex you have

03:42 layers structure. Okay. And if recall uh part of me, I

03:48 know where this keep sliding and control finger in the cortical organization. Which

03:54 cortex is found in mammals only. really organization of inputs and outputs the

04:02 is all of the sensor information and of the internal information from in between

04:07 circuits that is being processed and the . Ultimate output is the motor command

04:18 you're speaking and you have to move tongue or you're moving or you're running

04:25 you're picking up a pen or your . So this is the outfit.

04:31 all of the structure depends on function function depends on structure. So the

04:38 are inevitably intertwined neocortex means that its cortex so this still in self alone

04:49 different parts to in the cerebral But the top part of it is

04:55 neocortex is the sixth largest structure and neurons that are organized into columns and

05:07 . And what I mean by that if you look in the frontal parietal

05:14 temporal lobes you will have six layers are prominent layers and you can reveal

05:19 layers using the missile stain. So you have 1234 A. B.

05:26 56 layers. And you can see certain layers will contain densely more densely

05:34 cells. And this is reflected by more of this blue stain where each

05:40 of this punk tape, blue punk represents a cell. Now these cells

05:46 the layers if you stain up with stain will reveal to you that a

05:52 of the pyramidal cells let's say located in layer five there's so much located

05:58 lower five project they're dumb brides into ethical regions to they're one and the

06:06 down their eyes that radiate out in five. Use the missile stain again

06:13 will show you all of the And what's interesting is another stain is

06:19 stain. This is a new stain this stain is specific to axons.

06:25 if you use Weigert stain very quickly realize that there is there are these

06:31 are like if the layers are horizontal the neocortex then these columns.

06:40 These connections here revealed with wider stain that there is a vertical communication from

06:49 five or lay one or five or so whatever. So you have columnar

06:57 laminar structure that laminate for layers and for columns, columns. Essentially our

07:06 packed with neurons that process similar information have similar response properties such as visual

07:16 that are packed in the column will responsible for similar response properties in the

07:23 cortical area. And some of these are micro columns which means that they're

07:28 small and other columns are larger and called hyper columns. And we'll learn

07:34 that when we study the visual system we learn even more about this

07:39 Call a circuit. But this is really good introduction to this. So

07:47 local processing that happens. It's like local processing network in this. In

07:52 column. The cells will be processing type of information. There may be

07:59 columns located next to each other that be containing south of process the same

08:05 of information or very similar type of . So you have parallel processing taking

08:10 in these columns and these columns are laterally. So this lateral connections and

08:18 laminar organization allow for local processing within columns and then the lateral connections allow

08:28 wide and far reaching accidents and outputs to other columns and other court access

08:39 the depending on what the sensory paradigm paradigm is or what demands attention at

08:48 time. Visual information versus uh versus information and so on. So this

08:56 back if you remember to the santa methods of comedian Rodman Dr Rodman that

09:04 labeled all of these different areas in brain using missile state and it's very

09:12 that you have to use a combination these stains three or four, sometimes

09:16 or six. If you want to all of the cells. If you

09:21 to know subset of cells and all their processes like gold G. If

09:26 want to see where they project their . If you want to know if

09:31 are excited to inhibit their you may to stand for program or synthesizing or

09:36 enzyme. All right. So with help of all of these stains and

09:43 reveal a lot of interesting architecture in brain and uh another interesting piece of

09:52 is that neocortex is a structure. so much trouble with this person

09:59 Neocortex is a structure that is the structures that it's the new cortex.

10:18 . And other structures in the brain evolutionarily older. So we discussed because

10:25 stem, we talked about how brain has certain and is responsible for certain

10:32 body functions, right? We talked how brain stem will contain nuclei that

10:42 these means and producer means so without means. You know, there's obviously

10:48 evolution. Very important. Brain stem breathing hard trade. So without brain

10:58 or originally as a primordial human you were able to survive with brain

11:03 . Later these other structures telling. phallic structures developed more where you have

11:09 formation of the neocortex. The other thing in the evolution. And as

11:16 look at the different species from the order species, from rodents shown here

11:24 the right bottom to humans on the and cats in the middle here and

11:36 are several interesting features that are outlined , primary secondary motor and association

11:45 And what does this mean? What these colors mean? This means that

11:50 you looked at in a rodent if you look at a rat brain

11:56 you said, I want to know much of the rats brain is dedicated

12:02 processing primary visual information, decoding something basic. Primary about the visual stimulus

12:13 the visual world that you're seeing. this is the massive primary visual cortical

12:20 , massive auditory, the massive sensor . That means that this much of

12:28 brain, most of the rodent's brain dedicated to primary sensor information processing.

12:36 is secondary and what is association Well, let's first look at these

12:43 areas in the same color here and for visual information, auditory and sensory

12:50 in cats. And And humorous. what is in stark differences that these

12:59 ? Primary information processing areas in relatively to the rest of the size

13:07 the brain are very small and the you go in species, the more

13:16 the brain is dedicated to primary or , almost sensor information processing. Secondary

13:26 processing in the brain is more This primary visual cortical area and you'll

13:34 well about it later in the Primary primary uh primary auditory processing

13:42 Primaries, amount of sensitive processing your what is the best analogy of what

13:49 primary, what is secondary? There's tertiary areas, there's co ordinary and

13:54 areas and finally there's even association So what are these different things?

14:02 what is the best analogy? So best analogy is primary visual cortex.

14:11 give you a rough sketch in an of the visual world in the back

14:17 the occipital lobe. So take away of the features like death. Like

14:25 of the other features. Just a sketch of this room. Imagine a

14:29 sketch of this room. Yes. by the time you get to the

14:36 co ordinary, sometimes even Penton, visual information processing areas, you see

14:46 information with death perception, with all the movement, with everything else.

14:52 ? So now you have a complete information. But is this visual information

14:57 the absence of other senses? Like , smell, hearing? No.

15:06 association areas in the brain are the where all of the information for visual

15:16 , the confluence together it's areas where modalities sensory, visual auditory, emotional

15:27 come together coalesce in these association And most of the neocortex in the

15:37 brain says dedicated to the association That's where the complex stopped processing the

15:48 , the ability to process visual while listening to something and moving your body

15:53 maybe excited about meeting somebody. It comes together in these association areas to

15:59 how you what your output is, output, lingo output. Uh And

16:11 association areas is where the magic happens the brain, where the senses come

16:20 . And as you can see the developed the brains are, the less

16:32 is dedicated to primary sensory processing. more space is dedicated to secondary tertiary

16:39 association areas. When you're talking about this primal sketch and then tertiary or

16:48 you have a complete visual, it's hierarchical processing. There's a view if

16:56 took a view from the retina and it to the computer, what can

17:01 see, you would see these blotches color and that's about it. So

17:09 very simple by the time it gets the cortex, you're already seeing the

17:15 . By the time it gets to association areas, it's the whole

17:19 you will bless other senses blended together your thoughts internally blended together with an

17:28 . A lot of times you have processing in the brain that we talked

17:33 . The best example is you have and right. I it's in a

17:38 parallel processing. And if you take eye out, you don't lose half

17:42 the field is you actually you only the periphery on one side. And

17:48 significant because there is a significant overlap cross over the fibers that you want

17:53 individual system. Mhm. All So these are the major parts of

17:58 central nervous system. Once it you have the spinal cord which has

18:03 own divisions. Yes, Yeah, . The surface area. Okay.

18:13 your profit? They uh well, course they have been decided divine,

18:22 by the experiments of what the neurons capable of doing. Yes.

18:29 Oh, the boundaries are partly based the site, to architectural methods and

18:36 stands and the connectivity that you're And so if you put all of

18:41 things together, your question is If you put the if you put

18:46 structure and then you poke around with lectures and you get the function because

18:52 can you can put an electorate in back of the rodent's brain. You

18:58 , it's more difficult with humans. a lot of these studies were done

19:03 . But just to describe in a way you put an electrode rodent's brain

19:08 you show the visual stimulus and then move it quite far away and you

19:12 the visual stimulus and it's still only of doing a certain thing and reacting

19:17 certain way. Then you look at stain with the 34 states and you're

19:22 , Okay, these must be the now where exactly the boundaries are for

19:26 association areas. That's a more difficult way to define it because I would

19:36 as a neuroscientist is trying to understand brain for about 25 years. I

19:42 say that probably there is no clear . When you're talking about association and

19:47 of information that combines multiple modalities, there. But can you put a

19:52 around it and say that this is ? It's it's more difficult but with

19:58 and secondary and tertiary and you will beautiful anatomy and this amount of sensory

20:04 over rodent that we'll talk about barrel if you're not familiar with it,

20:09 that is there. You know, uh it's uh it all comes

20:15 you all have to have the the structure and the function together.

20:20 you're combining the dice functional studies, imaging and you can do that obviously

20:29 humans in vivo non invasively to will you determine these boundaries and what certain

20:36 are responsive to. It's a very question. Spinal cord is divided into

20:44 own regions, is divided into the region which is cervical into the store

20:50 region which is Jurassic into the lower back, lumberjack and sacral which

20:59 in your um tailbone essentially spinal cord and processes sensor information as you know

21:08 it receives and processes that sensor information . We're getting in south from skin

21:13 , muscles of the London trunk. controls through motor neurons, controls movement

21:20 limbs and trump brain stem is where of the sensor information which is comprised

21:26 maduro blow. God upon some midbrain information from muscles of the head,

21:34 control of head muscles. So you learn that there are cranial nerves today

21:38 control a lot of the activity. everything from MAC, down movement of

21:43 arms and feelings and everything is spinal from next up, you're talking about

21:50 nerves that innovate the upper regions of , of the cranium Brainstem regulates levels

21:57 arousal and awareness contains 12 panel nuclei are sensory motor. Some are responsible

22:05 both and can process special censuses involved hearing information, balance information and taste

22:15 processing at the level of the brain . So that's that's pretty cool.

22:21 is certain amount of information processing at level of the brain stem. Think

22:26 evolution, you heard something, your stuff could have processed a little rudimentary

22:33 in there. So we'll learn maybe . When you study the systems more

22:38 you learn what that's something they have . Wait medulla oblon gata, his

22:46 economic functions, breathing heart trade a bit digestive functions, calls right

22:56 They have these uh pete uncles that to sort of balance and a lot

23:03 uh motor information from cerebellum hemispheres. also have left cerebellum, right cerebellum

23:13 to cerebral hemispheres, information from cerebral too cerebral and vice versa from cerebral

23:23 to cerebellum. The belem is for range of movement. That's what it

23:31 and remember that it controls it. laterally as opposed to neo cortex of

23:36 cortex will put the command from the of the right side of the

23:41 What cerebellum all you're right cerebellum will the right side of the body force

23:50 range of movement, learning motor It's responsible for what we call a

24:01 that is procedural member, you know types of memories, semantic memory is

24:09 telling you a story and how you a story, semantic memory events,

24:16 , people names, procedural memory is you ride a bike, how you

24:26 serf. Yes. Are you How do you jump hurdles? And

24:36 is where the range and management of movement and fine tuning of the movement

24:43 motor commands that get initiated at the of the cortex and get adjusted fine

24:50 by the cerebellum. Uh And what's about procedural memories is that they cannot

25:00 erased unless there is a trauma or of the cerebellum. In other words

25:10 may forget, would you study in course after you take the test?

25:19 not. That's why I repeat things lot of times. Uh But you'll

25:24 forget how to drive a car, never forget how to ride a bike

25:30 if you haven't ridden a bike for years. Okay. You may fall

25:36 it will take your circuits maybe to with the balance. But it's not

25:41 you don't know how to ride a . Maybe you just haven't been in

25:46 kind of a appropriate sector uh motion environment. So it's very deeply

25:55 Pete Danko says what will connect To brainstem and that's where a lot of

26:01 , serverless cerebral cerebral, sorry Bella or so located midbrain a sensor and

26:08 functions including eye movement as well as of visual and auditory reflexes. So

26:16 what we're talking about. Special census . That's pretty cool. Visual and

26:21 reflexes. The brain stem. Again you think about evolution has some

26:26 Visual and auditory processing die and suffer thomas and the hypothalamus and we'll look

26:39 the following slides that show it all of the information from all over

26:47 . N. S. And round cortex goes through thalamus all of the

26:54 all of this is not a sensory information from the retina goes to the

27:00 before it goes into cortex. And has these massive paloma cortical connections from

27:06 to the cortex. And cortical thalamic from cortex back into palamos. Hypothalamus

27:13 below is involved more in the Gnomic in control of voluntary bodily functions

27:22 well as and Ukraine and visceral And hypothalamus is really a part of

27:31 endocrine system. Yeah. You ever of the H. P. A

27:41 ? You haven't don't worry about it it's a very important access to controls

27:51 release stress hormone release and therefore uh a way hypothalamus has a whole para

28:05 attacked on the human body. It serves as a gauge of the blood

28:13 it has very thin blood brain So it can detect some toxic molecules

28:19 to end up in the blog and detect changes in temperature. So it's

28:26 in thermal regulation hypothalamic pituitary adrenal That's what HP. A. Access

28:40 for. Uh pituitary. There's a gland. The cns actually talk about

28:49 again in the visual system. I . No is a Drina Drina

29:03 So you have this control of cortisol the system. And hypothalamus is involved

29:09 much so. And that regulation of induced hormone release cerebral hemisphere cerebral cortex

29:18 cortex major nuclei that serves some very functions basil ganglia which has a lot

29:25 the initiation and storage at least motor , complex motor commands, uh non

29:35 commands and motor patterns in the way which you know from the circuit perspective

29:42 hippocampus has all of these different subtypes inhibitory cells and excitatory cells. From

29:48 functional perspective hippocampus is responsible for learning memory, right? For encoding memory

29:59 also for retrieving memory. The hippocampus not store memory and memory. Different

30:06 of memories are actually widely distributed throughout brain to retrieve them. You may

30:13 to engage the hippocampal circuits again kind go back into the box here and

30:17 some member and drag it out through . It's also and influenced and is

30:24 in emotional information processing. But the , the hippocampus is responsible for a

30:30 memory, both short term memory and term members. The the encoding of

30:38 memory and retrieval of that memory. is another very important structure in the

30:46 that's involved with emotional response as Reading emotions, understanding emotions and other

31:00 from other faces. As long even behaviors. Use many parts of the

31:06 . So what is a simple Oh just throw a ball and hit

31:09 ball when you think about it Now start understanding if there's a player and

31:15 player is looking at the ball. means it's visual cortex is engaged and

31:21 anticipating something. So the visual cortex watching the ball, the pre motor

31:27 is concerned with, how am I to basically get ready and hit this

31:32 back. So it's already starting to engaged, What's gonna be the motor

31:37 ? You have other areas of the , you know, like a

31:41 It's from your synthesis emotional processing, motivation to hit a good shot,

31:52 cerebellum is adjusting fine movement and the way to think about the fine movement

31:59 maybe not tennis because in tennis you the ball flying and you have enough

32:03 to prepare and hit it back. racquetball, if you ever played

32:09 the element of surprise and racquetball is walls, there's no walls in

32:15 So when somebody hits the ball to to and it hits the wall,

32:22 can also have a spin. And spin can make the ball fly either

32:26 direction or stick closer to the So now was you prepared to hit

32:34 ball? The spin all of a is flying over here and now you

32:40 to fine tune that motor command that originated from basal ganglia, but you

32:45 have enough time. So then it fine tuned through serb alums middle management

32:51 and let's say instead of hitting this forum will turn around, it's not

32:57 the back are so motor pattern initiation on and the basil ganglia, you

33:07 uh appropriate exception. Also that's coming cerebellum. Where is my body

33:14 in in in location to the ground location to the net in location to

33:23 lime. Remember on how it hit game points ball. And thats hippocampal

33:34 telling you remember that that's part of semantic memory, how and you know

33:38 open 2019 I won this and it's of the whole game to motivation.

33:46 the behavior is initiated, you can it with the cerebellum. Of course

33:52 talking about brainstem, you're talking about body functions and keeping your heart rate

33:57 , respiration. Uh And it all to be in check because there's quite

34:04 lot of excitement. People that are the on the field for decades.

34:12 they still run out on the NBA after playing for 10 years. And

34:18 still that initial frighten anxiety and excitement you know, 20,000 people screaming at

34:26 good or bad and uh all of is a part of it. So

34:32 also have the ability to filter out focus on certain things to.

34:38 Mhm. So when we look at neocortex again, these are all of

34:46 familiar areas for us. Prefrontal this is pre motor area and this

34:53 primary motor cortex area for this is somatosensory cortex, on the parietal of

35:03 , this is the visual cortex area 18, 19 of the primary visual

35:08 . This is the auditory cortex Areas 41 42 is the primary auditory

35:16 areas. Uh There is a gustatory uh for sense of taste in there

35:28 . Diane cephalon nous allons information from over cns and route to cortex for

35:34 long time it was thought to be a relay station for information from the

35:41 from all of the sensory organs coming Fallon was before they go into the

35:46 . Again, cortex is hierarchically most , most advanced structure. So that's

35:52 you will get the complete absence of . And so the cells in the

35:57 are called relay cells really neurons are to re really neurons. And for

36:02 long time thomas was viewed as oh a relay station. So it's just

36:09 passive real. A there was a thomas is located all the way

36:15 There was a need for let's say information coming from the high to stop

36:20 the thalamus to relay that information to neuron that will carry that information to

36:26 exhibit alone where the visual processing takes . So at first it was believed

36:33 be real. A and then passive whatever reading the seas let's say is

36:41 to the thalamus thalamus relays that information the cortex. Original view. But

36:47 fact Alamos is responsible for gating. modulation of the signal gating can allow

36:55 signal to pass through and not the in a way. Okay. Can

37:01 modulate or can control the amount of that is dedicated to certain signal.

37:14 contains a particular formation. So what is thomas is a collection of a

37:21 bunch of the nuclei nuclear process, type of information. So all of

37:28 visual information will go through lateral gene nucleus. It's lateral and the balance

37:36 you'll find it laterally and it's a actually that's what it's called. Gene

37:40 , genius corny for bump. Nicollet nucleus install all of the

37:46 Visual information from retina will go into L G. M la roja nikola

37:50 and then from there it will go the primary visual cortex. All of

37:56 amount of sensor information will go through column, nuclear dorsal root ganglion cells

38:03 put it into the dorsal column In the spinal cord it will project

38:07 in the thalamus it will go into ventral posterior lateral nucleus. So all

38:17 this amount of sense of information is to pass through the vpl and routes

38:23 the somatosensory cortex auditor information. All the auditor information is going to go

38:30 medial nucleus nucleus and that is going go to the primary auditor. You

38:36 the gist of each one of these is dedicated to specific sense of information

38:43 and connects that sense of information How much of it comes in modulates

38:48 . You can see turns up the up and down and starting to censor

38:53 projects that into the into the cortex on top of that the cells that

38:58 really cells of these nuclear excited to . But on top uh this structure

39:04 top of these nuclear you have a of cells that is referred to as

39:10 particular formation or nucleus ridiculous Aris the nucleus. And this particular nucleus is

39:20 of a sheet of the inhibitory styles . So there's local interconnections between the

39:28 formation and excitatory cells. There's local of what is happening in the thalamus

39:35 well as the interconnections between the thalamus cortex and the cortex back to the

39:40 . The cortical thalamic and Philomel. where it originates is the first

39:46 It's a llama particle. That means fibers originated. Selma's send axons from

39:53 into cortex. Hypothalamus Alabama can voluntary the cream glands and hormones have already

40:01 about it. And the hypothalamus is underneath the columns. This is not

40:05 best picture. But we'll have a picture. I also bought a

40:10 appetite, water and take sexual activity of it lactation. Slow growth,

40:16 growth for hormonal release like growing growth growing slowly from being a baby into

40:25 ft whatever seven super charismatic nucleus which a part of the diane cephalon and

40:32 sitting there, it's a circadian rhythm . So it's a master body clock

40:37 responsible for controlling the diurnal rhythm. has transcription factors that influence you sleep

40:44 the evening mass transcription factors that influence levels of activity and stimulate them during

40:50 daylight hours. Okay, super charismatic , it's just sky as um it's

40:57 optic eye ASM and it's related to . This is another good view and

41:03 are all great exam question. So can point out these structures for

41:07 but you should know them by cerebellum, the visual cortex, this

41:13 the corpus callosum, this is mid view. That is a good exam

41:19 . Right, which plane was this made of corona, horizontal amidst natural

41:24 is mid sagittal view. You're seeing spinal cord, brain stem ponds.

41:32 , diane cephalon, You can see factory involves sticking out here. This

41:37 a singular gyrus shown in blue some these structures we will not have time

41:43 discuss, but I think you should almost everything that is on these diagrams

41:49 95% because we actually talk about 95 even more that is on here.

41:56 is located here and this is the right here, shown in blue embedded

42:03 three dimensions. So if a campus humans comes underneath in the temporal lobe

42:09 like that and in rodents it goes to the temporal uh loading up with

42:17 private lobes. Those structures are resemblance a similar but also have their own

42:25 in different species of animals. Four , sarah Palin has the left cerebellum

42:34 and the right cerebral hemisphere and in middle it has what is called the

42:40 . And so if you were to and cut off the cerebellum which you

42:45 expose as you would expose. The peed uncles. This is where all

42:50 these fibers from cerebellum into the cortex from cortex to cerebellum Iran. And

42:56 on the back you would expose. now you're looking from the dorsal

43:01 Okay this is a dorsal view. think you're looking from the back.

43:05 removed the cerebellum and now you're looking here. It was here. The

43:12 body here. Okay. And a famous structure that you're gonna know.

43:18 well I'm gonna ask about it almost re exam oil the corporate quadra gemini

43:26 it's very important for what we study like languages. Corporate quadra gemini

43:36 The body Wandera four gemini of Okay, this is the fourth structured

43:47 , essentially the two top structures of left and right, superior curricula.

43:53 when we talked about reflexive visual information . It goes through superior calculus,

43:59 of the fibers from the retina and going through the superior calculus. We're

44:05 ridiculous left and right where the auditor is going to be processed in the

44:11 . So most of it is reflective the level of the brain stem while

44:16 there is from auditor information for mediagenic inferior calculus it will go into the

44:24 list. Mediagenic Hewlett nucleus. They into the primary auditory cortex.

44:31 12 Cranial nerves. And why do learn them in this course? Because

44:39 gonna thank me for it. And we're gonna talk about few of them

44:47 we already discussed. A few of are quite a great detail. So

44:52 want you to know this. I you to know that this is obviously

44:58 side view of the brain And that have 12 nerves that are in the

45:07 . Stop. These nerves will now controlling a lot of things that are

45:12 in your mouth and your face and head. Yeah. So the first

45:20 is the of factory nerves which is shown on here. The second nervous

45:30 the optical optic nerve is shown And this is the front view showing

45:37 left and right optic nerve part of left and right optic nerve. Cross

45:45 , thrown off the sky as um super. Cosmetic nucleus the nucleus is

45:51 very close to the optic eye. and afterwards these become optic tracks.

45:58 these optic tracts are going to run the lateral gene, Nicollet nucleus of

46:04 thalamus and then into the primary visual . Mm three. Ocular Motor

46:16 What do you think that nerve The next thing is that a lot

46:20 cranial nerves if you remember or know they're supposed to do or what structure

46:25 related to optical is optical ocular motor still something to do with vision,

46:33 motor movement. Great movement of the , our killer motor. And you

46:40 at truck, me and her We're now going to study its

46:45 So I'm going to skip certain functions the cranial arms because they're not important

46:51 what we're going to review or they're making a point that I want you

46:55 remember. Number five nerve. You know because it's trigeminal nerve. It's

47:02 largest nerve stock right here. That out of the brain stem at the

47:08 of the ponds and it will have major fiber bundles making it trigeminal trigeminal

47:17 is incredibly important for controlling facial movement of facial muscles. Found speaking

47:27 so on facial expressions. So trigeminal you should know. Okay. Number

47:35 is abdu since Number seven is facial intermediary nerves. Number eight you should

47:47 because it's vestibular cochlear nerve. And we come to study the auditory

47:53 vestibular cochlear man has two components of balance and the cochlea. From the

48:00 leah here in component Glass of for is # nine. Glass of for

48:10 we'll also Gloucestershire, differential pharynx, tongue, ferries, tongue, pharynx

48:22 all of the your anatomy in medical . All of these latin words.

48:29 them up remember. It's a code , lateral gen equivalent. You already

48:38 what's media, what's lateral was gen . Okay, so the stimulus.

48:45 it's not one word. What is while it's a vestibule for waiting or

48:51 apparatus Biology vestibular cochlear cochlear to take words apart. Glass of for

48:59 Uh huh. You should know vagus because you know it already it runs

49:06 extensively and elevates the heart throughout the to this certain organs. Okay,

49:20 now we're up to town. Number is accessory nerve right here. That

49:36 not very important for us to We're not making a big point of

49:42 . But I will make a point high gloss on our number 12 because

49:46 just told you that glass Eliza So hypo what do you think this

49:54 above the time or below the tunnel the town. So it's controlled with

50:01 . So now what is it? are these nerves concerned with? Are

50:06 sensory by the motor? Are they ocular motor? That's pretty clear.

50:13 a modern nerve is gonna move the . What about the others? And

50:17 do you learn this kind of Mm hmm. Yeah. I'm trying

50:41 find the right slide. So how you remember the crane owners And why

50:49 you want to learn? Because if go to medical school you're gonna have

50:52 learn that you have to gonna have label them. And I went to

50:59 in michigan and we had a human as undergraduates. And our practical lab

51:07 of your anatomy and head and neck actually to label and identify these cranial

51:13 and human cadaver. So it's much difficult with what I had to

51:18 And so you should really try to is if you go to dental school

51:22 going to have to know these, to graduate school. Anything to do

51:25 neuroscience, you probably should know these unless you're just going to live in

51:29 cell and one molecule for a few which happens. So uh how do

51:36 remember these things? There is many pneumonic for remembering these things. So

51:42 was a dark and stormy cold evening michigan 1993. It's true and it

51:57 late and we had a study group we said how do you remember all

52:00 these things? And we came up a pneumonic, Bugs bunny says or

52:06 somebody copied it from somebody. But didn't really have access to internet that

52:11 at that time. There were We have pop three email accounts I

52:17 something like that. But so the was the following. Bugs bunny

52:24 oh oh to touch and feel very vegetables are So okay you can make

52:38 own. But since 1993 yeah I remember and I can close my

52:43 I can still recall all the cranial . So oh it stands, each

52:51 represents number one, oh there's no number two oh optic number three oh

52:58 ocular motor Uh two T. is clear touch tease trigeminal and six.

53:08 nuisance feel salmon facial. Very vestibular cochlear to green glass of original

53:19 vegetables. 10 accessory 11. Uh . Hi Gloss of 12. So

53:29 we have to come up with another that said which one of these nerves

53:35 ? Which one is motive? So come on. It was Bugs bunny

53:41 so, so much money. But brother says, bugs bunny makes more

53:51 in this case the first letter. . Of the word for em or

53:59 . If it's s it's a sensory . If it's m it's a motor

54:06 and you can help yourself by remembering or because three is a motor and

54:13 ocular motor nerve. So if you three is motor and you had a

54:18 in the exam between two and one them was not. Do you remember

54:22 ocular motor? You would get that . So B. Stands for

54:27 That means the nerves are capable of . The sensory information and the modern

54:33 . So, so so much So number one sensory or factory to

54:40 sensory No three. Ocular Motors. Nerves. Number five which is

54:47 These are the important ones are going now or both. Okay, number

54:54 which is the stimulus. Coakley a nerve number 10. Which is

55:02 It's both. Yeah, censoring Very, very cool. So now

55:13 know the cranial nerves. And once the important ones, you should know

55:19 one of factory because it's easy. if you remember number one of factory

55:24 you'll remember the two is optic. smell one eyes too moving eyes.

55:31 ocular motor five try germinal eight. to be with cochlear 10 Vegas.

55:42 no these that I just named know their sensory and motor of both and

55:48 gonna be all set for the exam . Okay. And this pdf is

55:55 your lecture notes. So you'll find in your lecture notes, The

56:08 Okay so Spinal Cord, an overview the divisions of the spinal cord 1st

56:19 nerve. And you have cervical vertebrae . one And seven cervical seventh cervical

56:30 and right below it you have the cervical nerve. So you have the

56:36 cervical vertebra and you have eight cervical as their neck. So when people

56:45 I had a surgery in C. Or something is in c.

56:51 Or a disc slip in L. . So C. Is cervical

56:57 Would be lumber T. Of course thoracic. And you have T.

57:02 through T. 12 thoracic vertebra and thoracic nerves Number one through 5 for

57:09 back and lumberjack. And then you sacral vertebra and sacral nerve here coming

57:15 here. Another thing to notice about cord. Is that spinal cord proper

57:21 one continuous structure like sort of a continuous cord stops at about L.

57:30 L. Three. Then from there it becomes what is called cardiac

57:36 So the fibers actually no longer enclosed one structure. Would rather spread out

57:42 card it's called it tail A quien tale called oh you see it's the

57:50 language called a nucleus Cardell. In the back versus raw stroll.

57:58 . Uh Called a queen, a , equestrian horses scale. So the

58:05 look like loose fibers like horse's tail enter the lower structures and the the

58:15 uh and the legs. And you know this that the information that comes

58:22 the spinal cord goes through the dorsal ganglion. That's where the, so

58:27 of the DRG cells are located. project into the spinal cord. And

58:33 a lot of the sensor information will carried through these dorsal columns.

58:40 so this information is going to ascend the spinal cord into the cortex.

58:45 talked about reflex artists. That happened the level of the cortex. But

58:51 of the information sensor information was also the level of the spinal cord.

58:56 all of the information from the spinal is also sent up into the

59:01 So you have this lateral dorsal column you can see that the spinal cord

59:07 the shape. Sometimes it's referred to a butterfly. Other times they're called

59:13 . It has dorsal horns to dorsal and then it has ventral horns dorsal

59:20 is where the fibers and DRG south command you. And you'll have some

59:25 much here of the inter neurons and neurons. And then ventral horns is

59:29 the motor neurons and their outfits will out through the ventral side. And

59:36 three men in jeans, the S. A. Barack annoyed.

59:40 the dura mater that cover the spinal proper. And going back to this

59:47 showing where the spinal cord proper You will see that when we discussed

59:53 time, if there is an infection the brain and you need to take

59:57 sample of cerebrospinal fluid, that sample cerebral spinal fluid will actually come Right

60:06 L. 203. So they will a softer needle to try to drain

60:12 of the fluid from the canal there that area. Okay, so we

60:19 this dorsal and ventral information processing at spinal cord. As I mentioned,

60:26 a lot of fiber bundles that are in the spinal cord, the major

60:31 pathways the dorsal column to all of information and then all of these are

60:38 motor pathways. You have the cortical rubio, spinal the jewelry, ridiculous

60:45 texas, spinal pontin, ridiculous. track the stimulus, spinal track.

60:51 lot of the names of these tracks again the stimulus spinal goes from the

60:56 apparatus to the spinal cord. What you think? It does? The

61:01 apparatus? It helps you balance and tracking the balance on how the motor

61:06 move your body and the output from motor neurons into the body within that

61:12 . And of course we have the peripheral nervous system, a lot of

61:18 visceral ganglia. We talked about Terek nervous system, how many esoteric

61:25 system is just as complex. And thing that we always want to know

61:33 the brain is we want to understand function. So now you understand the

61:39 structures in the brain. Okay, we talk about the visual system will

61:46 back and you'll understand more details about retina and the circuit and the retina

61:52 processing from thalamus into cortex. What's into cortex with types of cells are

61:58 ? But this is a broad general of how from these three primordial tissues

62:05 have the Folding your relation differentiation in structures and what functions these different structures

62:13 in the brain including the 12th cranial . We want to always know of

62:22 how to image that information in the . And so I attached a couple

62:31 interesting articles for you in your lecture . So if you go to your

62:39 notes you'll find a one of the that is called voltage sensitive dye

62:49 Okay and there is both a sensitive pdf and there's a review that I

62:55 there. Why didn't want to talk that? Because I want you to

62:59 building and understanding uh how you can different activity in the brain and what

63:08 the levels of this imaging. But can be accomplished in the clinic and

63:13 can be accomplished in the lab in clinic. The tops of imaging that

63:19 will be doing are called macroscopic And maybe Mezza skah pick imaging.

63:30 imaging will give you a nice view large parts of the brain that are

63:36 for visual information processing. Then you take a specific area of the brain

63:42 as the one and you can start into the breakdown and may be differences

63:49 activity within that specific. Not how specific area is different from the rest

63:53 the brain but what are the differences different parts of this specific area that

63:58 looking at then? What is a in the part of the area that

64:04 can you can look at it Is it circuit centric? So can

64:08 go to the circuit level using MRI pet scans? Noninvasive human imaging?

64:15 it's not there yet. So all the functional imaging again. Why do

64:21 want to have functional imaging? Because understand the structure. We have all

64:26 these stands Missile Golgi Weigert this and know it's the chemistry. I want

64:33 see the function. I want to the function not only at this macro

64:40 which is under a microscope. Macroscopic . It's not a microscope again but

64:46 a microscope. You're looking at large areas. I want to go down

64:52 sub cellular level. I want to down to single sanat. I want

64:55 engage Glutamate on one dendritic spine and want to see what activity happens in

65:03 introduce, find what activity happens in cell. What does that cell communicates

65:08 the rest of the network in the ? How does a larger network see

65:14 communication? What does it mean for rest of the brain? So these

65:20 all of the levels. And then it comes down to circuit centric cellular

65:25 sub cellular, you're utilizing experimental So we already touched on some of

65:32 human imaging techniques and we'll come back this in the second. We want

65:36 show you a technique that is called sensitive dye imaging. Okay, and

65:46 is a technique where you have a ope. This is a macroscopic ope

65:52 is going to be imaging activity in part of the brain experimentally. You

65:59 now do two things. There are very intriguing dyes that are called voltage

66:05 dyes intriguing because they embed themselves within plasma membrane. These little squirmy warrants

66:13 they have certain reflective properties depending on . So they said, resting membrane

66:20 . Big blue blue and then once membrane potential across the channels protein channels

66:27 the charge across a number of These squiggly warms changes the confirmation and

66:33 in the membrane And instead of blowing the chemical dye molecules are not one

66:41 chemical dye molecules but they changed their depending on the voltage across plasma.

66:47 it? And now they glow Well now they glow red and this

66:52 you a really nice view of what happening. And so everywhere you're seeing

66:58 here are active cells, everywhere you're blue, there's a significant amount of

67:02 addition, so now using both of dye imaging when we talked about

67:09 remember in the pre synaptic synopsis, imaging of calcium, I said there

67:13 specific dies for measuring levels of calcium dies from measuring levels of sodium

67:20 you name it but you also want know how the membrane potential changes and

67:25 want to know that actually in a cell level if you can on a

67:30 level and voltage sensitive dye allows it do it almost on a single cell

67:36 , Almost from a single cell But the point being is that in

67:40 to achieve this. And what else you want to do to confirm that

67:45 diet is actually recording the number of you want in certain an electrode as

67:50 insert an electrode, you're tracking this . So one of these traces is

67:57 optical change. Okay, in the . Another one of these traces is

68:05 number of potential change. So attracts with these voltage sensitive dyes and that's

68:12 significant and to finish in humans. we talked about early on, we'll

68:20 talking is have computer tomography ct Very popular And clinic with their essentially

68:29 dimensional X ray X ray is really to see gross changes in the brain

68:38 between hard and soft matter and MRI. You have magnetic resonance imaging

68:46 items, no X ray, you more detail. But when you talk

68:50 functional imaging, you have path which positive on the mission of demography and

68:56 , The brain and the cells in brain. They require a lot of

69:00 . It only comprises about 3% of total body mass. It consumes over

69:06 of the total energy that you're putting your mouth and skin and everything

69:11 Okay, so it's a system that a lot of blood. When neurons

69:16 active, they demand more blood. they demand more oxygen. So you'll

69:22 increases regionally in the oxygen levels. demand more food. What is food

69:28 neurons glucose. So they demand more . So here are your clues to

69:33 do you track your own or Can you put the dye in the

69:37 brain vote for something to die? like in that monkey experiment and put

69:42 hole in the image and send them and come back an image again

69:47 So you have non invasive techniques and you have to track blood. You

69:53 to track oxygen. You have to glucose. These are the core things

69:57 you want to track when you're tracking . The MRI. You have hydrogen

70:02 one proton, high energy or low state, fluctuate the frequency at which

70:08 low state pro tiles absorb energy is resonant frequency. So the frequency at

70:14 it basically goes between the low and high energy states. And then in

70:21 radio waves by protons and then you these magnetic coils and it's essentially electromagnetic

70:28 . It gets absorbed through these coils presents a nice image of the

70:33 And F. M. R. F. Stands for functional magnetic resonance

70:39 . Yes. So functionally you you have an FmRI changes between oxy

70:51 and the oxy hemoglobin ratio hemoglobin is molecule in the blood that carries

71:00 So if you're gonna draw more activity gonna draw more oxygen. You're actually

71:06 to have more deoxygenated hemoglobin then Because those neurons are going to be

71:14 information and draining the oxygen. So the basis for FmRI. The basis

71:21 pet is radioactivity active solution with charged is injected in the bloodstream. So

71:31 is somewhat invasive. You're putting something FmRI. You're not really injecting it's

71:36 contrast liquid of contrast material. But X ray with CT scans and with

71:44 you're being injected a material protons bind in the mid electromagnetic radiation and what

71:51 measuring through pest Kansas glucose consumption With d. oxy glucose. So

72:01 You're looking at oxygen. And with you're looking at glucose consumption.

72:09 going back to the same story that are the most important functional aspects in

72:14 to membrane potential. But right now nothing that in humans can non invasively

72:21 fluctuations and membrane potential. The slightly with TMS stimulation, strength, magnetic

72:29 that you can do that but it's being worked out of these stages where

72:35 may become an acceptable way in the of pinpointing information. The problem with

72:42 coils that measure information as they have access information deep and accessing information deep

72:49 actually blur that. And as far extracting exact information happening versus diluting it

72:56 some average or an interference that's coming the structure about. So we're going

73:03 end at this stage and on Wednesday watch the lecture on the retina on

73:09 visual system. The first lecture and will be back here with you on

73:17 . Thank you for being here. your questions for next time as I

73:21 to run out. And that will your quizzes later. Today or

73:30

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