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AnatomyCNSpartA — Transcript

by Dr. Naveen Jalota, M.D. · 7,927 words · 1,502 segments · language en · Watch on YouTube

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0:01all right let's start
0:03here by talking central nervous system
0:05now
0:06um this is the part 13b 15a
0:10uh that lecture that we have online
0:12there
0:13so here now when we go through we talk
0:15central nervous system we've gone
0:16through we've talked about the divisions
0:18there already we've seen
0:19central nervous system is going to be
0:21made up of the brain and the spinal cord
0:23so here now when we go through and we
0:25talk about the brain and the spinal cord
0:27we'll get
0:28the brain taken care of first and then
0:29we'll check out the spinal cord
0:31now when we go through we talk brain i'd
0:33like you to know the brain
0:35is described as being about four good
0:37fistfuls
0:38it's described as being about four good
0:40fistfuls
0:41of a quivering of a quivering
0:45pinkish gray tissue
0:50the brain is described as being wrinkled
0:54like a walnut it's wrinkled like a
0:56walnut
0:57and it has a consistency of that of
1:01a cold oatmeal
1:04now when we go through we describe the
1:07brain the brain is being described as
1:09weighing 3.5 pounds
1:12in the mail and being about 3.3
1:16pounds 3.2 pounds in the female so
1:203.5 pounds in the male and 3.2 pounds
1:23in the female and now that's because of
1:25the body mass
1:27brain mass equivalency basically in the
1:30sexes
1:31uh now when we talk average average male
1:33female brain weighs about 3.3 pounds
1:36okay now when we go through we talk uh
1:41brain development and whatnot first what
1:43we want to do is we want to go through
1:44and look at the development of the
1:45nervous system as we can see here on our
1:46slides
1:47now when we go through we talk about the
1:49development of the nervous system what
1:50we're going to do is we're going to go
1:51through this process called
1:53neurolation and we're going to look at
1:55the development of the nervous system
1:57here
1:57so here when we go through this process
1:59of neurolation
2:01here we're going to see now in this
2:03process of neurolation
2:05here what we have is uh we're going to
2:08go through we're going to look at this
2:09whole process of the formation of the
2:11neural tube is basically what we're
2:12getting at
2:14now here okay there we go
2:17all right so here now when we go through
2:20and we
2:21talk about the development of the
2:22nervous system first
2:24we've got this process of neurolation we
2:25want to look at now here what's going to
2:27happen is you'll see around
2:29the third week uh the third week what's
2:32going to happen is
2:33the ectoderm thickens here we can move
2:36over to
2:37the next few slides here we can
2:38appreciate now
2:40basically uh the dorsal aspect here you
2:43can see that
2:44ectoderm starts to thicken when the
2:47ectoderm starts to thicken
2:49it's going to give rise to the neural
2:52plate as we can see here
2:54so the ectoderm thickens right
2:57forming that neural plate at the dorsal
3:01midline axis of the embryo at the dorsal
3:05midline axis of the embryo now this
3:08neural plate that we see here this
3:10neural plate now itself is going to
3:12invaginate
3:14now here you can see when we move over
3:15the next slide it invaginates it moves
3:18you can see to a more deeper position
3:20forming for us
3:21what we refer to now as the neural
3:23groove the neural groove itself is
3:25flanked
3:26by the neural folds you can see there on
3:28both sides
3:30now as this neural groove deepens
3:35the superior edges of the neural folds
3:38are going to fuse
3:40and when they fuse you can see here
3:42forming for us
3:43our neural tube the neural tube
3:47detaches and it sinks to a deeper
3:50position
3:51so it detaches and it sinks to a deeper
3:53position
3:54and there then we can see this neural
3:56tube and the reason why this neural tube
3:58is important is because this neural tube
4:00then we're going to see is going to be
4:02formed
4:04in one week you can see so by the fourth
4:06week
4:07you can see now that neural tube is
4:09formed
4:10now this neural tube is important
4:12because this neural tube is going to
4:13differentiate into the central nervous
4:14system
4:16it will differentiate into the cns
4:21now there's also some neural tube
4:23defects that i need you guys to know
4:25about now
4:26neural tube defects uh here we're going
4:28to see we've got uh
4:30uh basically we can appreciate
4:34the development here in this picture as
4:36well going through various stages
4:38same thing we can see here and the same
4:40thing we're going to see in the next
4:41picture
4:43and here we can see a couple of neural
4:44tube defects that i want you to know
4:46about a few
4:47first we've got spina bifida second then
4:49you've got microcephaly and then we've
4:51got an encephaly
4:52now spina bifida is going to occur they
4:55say it's linked to a folic acid
4:57deficiency
4:58so folic acid not being plentiful
5:00basically
5:01in the uh body excuse me at the time of
5:05the neural tube
5:06formation now here when we talk spina
5:10bifida spina bifida you can see here
5:11we've got two different types
5:13we've got a colton we've got cystica now
5:15here what's going to happen in this
5:16problem is the vertebrae is going to
5:18fail to enclose the spinal cord
5:20so the spinal cord is not going to be
5:22found enclosed within the vertebra
5:25and uh we talk cold occulta it happens
5:28uh
5:29by affecting one to a few vertebrae and
5:32uh there's no functional problems there
5:34and then spina bifida cystic is the more
5:36severe form where then the sac
5:39basically protrudes from that spine uh
5:41and you can see basically even these
5:43components are going to be found in
5:44outside of the vertebra now you've got
5:46microcephaly micro the prefix you've got
5:48there
5:49for small brain and then an encephaly
5:52you got there basically these patients
5:53have no brain there
5:55now when we move over to the next slide
5:57you can appreciate an encephaly here
5:59and then we've got spina bifida we can
6:01appreciate here
6:02and also spina bifida in this picture
6:04down here as well
6:08next on here this uh neural tube is
6:11going to be important because this
6:12neural tube
6:13is going to give rise to the cns but
6:15before it gives rise to the cns
6:16here we're going to see it's going to
6:17form our five uh it's gonna form first
6:20our three
6:21primary brain vesicles we're gonna go to
6:23we're gonna look at and then there
6:25those three you can see now are formed
6:27uh basically uh right after that fourth
6:29week and then the fifth week
6:31uh we're going to see here uh our
6:33secondary brain vesicles are going to
6:35appear and then they're going to
6:36differentiate into the second
6:37into the adult basically into the
6:41adult brain structures that we're going
6:43to eventually have we'll say
6:46all right so let's go through let's talk
6:47about then these are primary brain
6:50vesicles
6:51so again here you can see the formation
6:52of the neural tube
6:55same thing happening here and then here
6:58you can actually see all the different
6:59uh
7:00brain structures
7:04so when you say brain it's not just one
7:06part you can see there's a whole bunch
7:07of different parts there
7:10now here we can see the neural tube the
7:11neural tube now we can see it's going to
7:13start to
7:14its anterior end starts to take shape
7:16and starts to change shape basically
7:17there and gives rise to the cns
7:19structures
7:20so here you can see that neural tube
7:21before all of that happens and here you
7:23can see the primary brain vesicles
7:25actually formed
7:26so here we can see now when we talk
7:28primary brain vesicles
7:29as soon as the neural tube forms its
7:32anterior
7:33end begins to expand
7:36forming the brain and the remainder
7:39becomes the spinal cord
7:43excuse me the remainder is going to
7:44become the spinal cord
7:51we've got here first prosencephalon
7:54second
7:54mesencephalon third then you've got
7:56rhombencephalon
7:58forebrain midbrain and hindbrain we can
8:01say there as well
8:03now prosencephalon mesencephalon and
8:05roman cephalon are going to give rise to
8:07secondary brain vesicles
8:08here we can appreciate our five
8:10secondary brain vesicles
8:12that you're required to know about there
8:13then so telecephalon diencephalon
8:16mesencephalon continued on and then met
8:19encephalin and myelin cephalon
8:21you can see there came from
8:22rhombencephalon so prosencephalon
8:25gave rise to telon telencephalon and
8:27diencephala
8:29now when you talk secondary brain
8:32vesicles you can see these secondary
8:33brain vesicles are going to give rise to
8:35adult brain structures
8:36now those adult brain structures you can
8:37appreciate from each secondary brain
8:39vesicle you can see
8:41right inside of here in the second
8:43column here and then
8:44you've got the ventricles that are
8:45associated with each of those segments
8:47here in the last column
8:50so when we talk telecephalon
8:51telencephalon or your
8:53end brain it's going to give rise to the
8:57cerebrum
8:59talk cerebrum you can see there it
9:01consists of your cerebral hemispheres
9:03and when you talk cerebral hemispheres
9:05your cerebral hemispheres are going to
9:06consist of cortex again the outer part
9:09the bark white matter
9:13and also basal nuclei and we'll go
9:15through a look at the cortices
9:16white matter and basal nuclei today in
9:18greater detail
9:22next then we've got our diencephalon
9:26when we talk diencephalon diencephalon
9:28is also known as the interbrain
9:34it gives rise to the thalamus
9:36hypothalamus and epithalamus
9:39so you can see there diencephalon in the
9:40retina
9:43diencephalon in the retina and then
9:45we've got
9:46mesencephalon mesencephalon gives rise
9:50to the midbrain that's going to be one
9:52segment one division of the brain stem
9:56and then met encephalon mettencephalon
9:59will give rise
10:01to we can see the pons
10:04and the cerebellum also going to be
10:07formed here
10:08and then last we have myelin cephalon
10:12myelin cephalon will give rise to the
10:13medulla oblongata of the brain stem
10:16to the medulla oblongata and then we
10:18said the rest
10:19is going to give rise to the spinal cord
10:28so next up we've got the adult brain
10:29structures so you can see all of them
10:31listed there
10:32and here we can actually appreciate them
10:35then throughout development so here you
10:37can see
10:38in week five you've got these flexures
10:40basically this space here
10:41the midbrain flexure and then here we've
10:43got the cervical flexor
10:45and you'll see they're going to start to
10:46move basically and then they get
10:48eventually occupied by
10:49sp brain parts and fully
10:53basically occupied and completely
10:55disappear there then
11:00as we can see there to birth
11:04so here then eventually are the uh adult
11:06brain structures so they're formed there
11:08what's gonna happen now is just
11:09the growth is gonna occur and they'll
11:11grow too then
11:12uh basically their sizes
11:16so here let's check out uh the general
11:19organization now
11:20uh let's check out the adult brain
11:22regions uh we've got first the cerebral
11:24hemispheres you can appreciate here
11:26there's one of the cerebral hemispheres
11:28on the other side then would be the
11:29other one
11:30and then diencephalon you can appreciate
11:33right inside of here and then we've got
11:37the brain stem which is made up of
11:39midbrain
11:40pawns and then we said the medulla
11:42oblongata
11:44and the rest spinal cord
11:50so ventricles in we talk ventricles now
11:52ventricles i want you to know are going
11:54to be
11:54fluid filled chambers they are fluid
11:58filled continuous enlargements you can
12:02think of fluid filled
12:04continuous enlargements formed
12:08by the central cavity of the neural tube
12:11formed by the central cavity of the
12:14neural tube
12:20so like i said they're continuous with
12:22one another they are continuous with one
12:24another
12:25not only are they continuous with one
12:26another but they're also going to be
12:27continuous with the central canal
12:29of the spinal cord they will also be
12:32continuous
12:32with the central canal the spinal cord
12:36these ventricles we'll see are going to
12:37be filled with csf
12:40they are filled with cerebral spinal
12:42fluid
12:44and then they are lined by ependymal
12:47cells
12:48they are lined by ependymal
12:52cells
12:56one type of neuroglia that we've gone
12:58through we've talked about you should
13:00recall
13:02so let's go through and let's check out
13:04these ventricles in greater detail first
13:05we can appreciate here
13:06our lateral ventricles now when we talk
13:10lateral ventricles the lateral
13:11ventricles are going to be found as a
13:13pair
13:14so from the anterior view you can
13:15appreciate both of them there
13:17and then from the lateral view you can
13:18appreciate both of them there as well
13:22so they're found as pair they're paired
13:26in the cerebral hemispheres
13:30large c
13:33shaped chambers
13:37like the letter c c shaped
13:40chambers anteriorly
13:43you can see from the anterior view
13:45anteriorly
13:47they lie close together
13:50you can see here they're found lying
13:51close together however they are
13:53separated
13:54they're going to be separated by the
13:56septum pellucidum so they're separated
13:59from each other by the septum pellucidum
14:04and we'll talk about that in a few
14:05seconds now these ventricles are so big
14:07they get divided up into different horns
14:10so here we're going to be able to
14:11appreciate first the
14:12anterior horns
14:17back here you've got the posterior horns
14:20and then down here we've got the
14:22inferior horns
14:26so septum pellucidum the septum
14:28pallucidum i want you to know is a thin
14:31median a thin median
14:35membrane a transparent wall you could
14:37think of
14:43next then we have our third ventricle
14:46now the third ventricle is a narrow
14:50fluid filled chamber it's a narrow
14:54fluid filled chamber
15:01and the third ventricle is found in the
15:03diencephalon
15:07and it communicates with the lateral
15:10ventricles
15:11it communicates with the lateral
15:13ventricles
15:14and it communicates with the lateral
15:16ventricles you can see here from this
15:18anterior view
15:20via the inter ventricular foramina
15:25or the foramen of monroe so you can see
15:27there's two of them they allow each of
15:28these ventricles to communicate with the
15:30third ventricle
15:38next then we have the cerebral aqueduct
15:41so we're moving down to the fourth
15:44ventricle
15:45now between the third and the fourth
15:47ventricles you have the cerebral
15:49aqueduct
15:50so the cerebral aqueduct is going to
15:52allow
15:54third you can say connects the third and
15:56the fourth ventricles
16:00it's canal-like so hence the name
16:06aqueduct
16:08next then we've got our fourth
16:20ventricle
16:32so sorry about that so here when we go
16:34through we talk then
16:35the fourth ventricle fourth ventricle
16:38now we're going to be able to appreciate
16:40here
16:40very well from the anterior view and
16:42then here from this lateral view
16:44now we talk fourth ventricle the fourth
16:46ventricle is going to be found
16:48in the hindbrain so in the hindbrain
16:52dorsal to the pawns dorsal to the pawns
16:57and superior to the medulla and superior
17:00to the medulla
17:01so again the third and the fourth
17:02ventricle will communicate
17:04with one another with each other via the
17:07cerebral aqueduct
17:11so fourth ventricle is going to be found
17:12located dorsal to the pons and superior
17:15to the medulla
17:18and then here we can appreciate these
17:19apertures you've got your lateral
17:21apertures
17:22and here you can see the median aperture
17:24now these apertures are going to
17:25basically connect the ventricles
17:27to the subarachnoid space to the
17:30subarachnoid space and that's a fluid
17:32filled space again
17:34that's going to be found surrounding the
17:35brain
17:38and you guys will see that in the next
17:40chapter in greater detail
17:43now let's look at the central nervous
17:44system arrangement let's look at the cns
17:47arrangement
17:48we're going to basically look at how
17:49this white matter and gray matter are
17:51going to be organized
17:52so here we can go through and we can
17:54look at first these different regions
17:57of basically the cerebellum the brain
17:59stem and then you can see the spinal
18:00cord there as well
18:01so here now we're looking at the pattern
18:03of gray and white matter in the central
18:05nervous system
18:06now here first you can see we've got the
18:08central cavity the central cavity right
18:10at the center
18:11fluid filled space right we've gone
18:13through we've talked about that and
18:14we've checked that out
18:15now here then you can see surrounding
18:18that central cavity is going to be inner
18:20gray matter core the inner gray matter
18:22core this inner gray matter core is
18:24going to be
18:25gray matter mostly neuron cell bodies
18:29it is again gray matter mostly neuron
18:31cell bodies
18:33next up we've got the outer white matter
18:36you can appreciate then this outer white
18:38matter
18:39now this outer white matter is going to
18:42be white matter again and it's mostly
18:44myelinated myelinated fiber tracts
18:48myelinated fiber tracts
18:51next then we have gray matter nuclei
18:55now we talk gray matter nuclei
18:58here we're going to be able to go
18:59through and we're going to be able to
19:00see now
19:01when we talk gray matter nuclei now gray
19:04matter nuclei
19:05are going to be basically found
19:08now you can see here at the level of
19:11that cerebellum
19:13right inside of there and then we've got
19:15some more gray matter nuclei
19:17you can appreciate here at the level of
19:19the brain stem
19:22next then we have the cortex of gray
19:25matter now we talk cortex of gray matter
19:27again
19:27that's only going to be appreciated in
19:29certain regions here we can see
19:31at the region of the cerebellum we've
19:33got this cortex of gray matter
19:35right outside of there and we will look
19:37at this again
19:38when we look at and we talk about the
19:40cerebral hemispheres
19:43so let's go through and let's look at
19:45then the cerebral hemispheres now
19:47uh the first component of the central
19:49nervous system in greater detail
19:51so we've got nice view here and then we
19:53can appreciate this view here
19:55same thing here with these next few
19:57views
19:58there as well so we talked
20:01cerebral hemispheres i want you to know
20:03the cerebral hemispheres
20:05are going to form the superior part of
20:07the brain
20:08they form the superior part of the brain
20:12they the cerebral hemispheres they cover
20:16they cover and they obscure the
20:19diencephalon
20:20they cover and they obscure the
20:23diencephalon and you can see that there
20:25very well
20:27this is a an image that's showing you
20:29actually through the hemispheres
20:32but that's not normally what you would
20:33find so you could see the cerebral
20:35hemispheres are going to cover and
20:36obscure the diencephalon
20:38and the top of the brain stem and the
20:41top of the brain stem
20:43now there's markings here that we can
20:45appreciate as well
20:46now these markings we can appreciate on
20:48the hemispheres you can see here very
20:50well
20:51the gyri now these gyri
20:54are elevated ridges of tissue
20:57they are elevated ridges of tissue on
21:00the surface of the cerebral hemispheres
21:03elevated ridges of tissue on the surface
21:07of
21:07the cerebral hemispheres now between
21:10these
21:11gyri you can appreciate sulci now the
21:14sulci
21:15are going to be shallow grooves
21:18they will be shallow grooves
21:22that you can appreciate now right inside
21:24of there
21:25so here all right so here we can
21:28appreciate then again
21:30gyrai and the sulkai so when we talk
21:33sulci
21:34sulci are going to be again
21:37we've got uh play from current slide so
21:40when we talk sulci
21:41soka are going to be the shallow grooves
21:43the shallow grooves you can appreciate
21:45in between these elevated ridges of
21:48tissue between these gyri
21:50now when we talk fissures fissures then
21:53are going to be
21:54deeper grooves they will be deeper
21:57grooves
21:58or you can think of a deep sulci
22:02or a deep sulci
22:19next in here we've got two fissures
22:22so deeper grooves or a deep sulci
22:25now these fissures we'll see there's two
22:28of them that i want you to know about
22:29first you're going to be able to
22:30appreciate
22:31you've got longitudinal fissure now the
22:33longitudinal fissure
22:34is found separating the cerebral
22:36hemispheres at
22:37the midline so first fissure you have is
22:40a longitudinal fissure
22:41the longitudinal fissure separates the
22:44cerebral hemispheres
22:45at the midline next then you have your
22:49transverse cerebral fissure
22:51now the transverse cerebral fissure is
22:53going to be found
22:55now separating the cerebral hemispheres
22:59you can see above found separating the
23:01cerebral hemispheres
23:03from the cerebellum below from the
23:06cerebellum
23:06below
23:10so two major fissures we want to cover
23:12there as well
23:14and we have a lateral sulcus we'll talk
23:17about
23:18also you can appreciate
23:21right inside of here
23:24so we'll talk sulci as we progress as
23:27well
23:28next then let's go through and let's
23:30talk and let's look at the divisions the
23:32of the brain the cerebral of the
23:34cerebral hemispheres
23:35into lobes so let's see how they're
23:38divided up into lobes
23:39here you're going to be able to
23:40appreciate basically all the different
23:42lobes i'd like you to know about here
23:43you've got the frontal lobe
23:45we're going to go through we're going to
23:46check out we're going to talk about that
23:47we're going to see the parietal lobe
23:49and then we've got the occipital lobe
23:51and then here we've got the temporal
23:53lobe
23:54and then the fifth lobe is going to be
23:56the insula
23:58the insula so here you can see now
24:01five lobes in total there's five lobes
24:04in total
24:05they're divided by the sulci divided and
24:07separated
24:08uh from one another by the sulci
24:12and they're named these lobes are named
24:15for the cranial bones that overly them
24:18they're named for the cranial bones that
24:20overly them
24:22first you've got the frontal lobe
24:25frontal lobe now is going to be
24:27separated from the parietal lobe
24:29thanks to the central sulcus so here you
24:31can appreciate
24:32the central sulcus you can see it's
24:34found separating that frontal lobe from
24:36the parietal lobe
24:38next then we're going to be able to
24:40appreciate that parietal lobe the
24:41parietal lobe
24:43you can see here very nicely
24:47now in relation to the frontal lobe and
24:49parietal lobe we've got
24:51your pre central gyrus and your post
24:54central gyrus
24:56pre-central gyrus you can see is going
24:58to be found anterior
25:00to the central sulcus so you gotta
25:02listen to the terms
25:04pre-central gyrus
25:08anterior to the central sulcus
25:10postcentral gyrus
25:12dorsal posterior to that central sulcus
25:16and they're going to be two important
25:17structures we're going to go through
25:18we're going to talk about
25:20so there is your parietal lobe
25:23parietal lobe then is separated from
25:25this occipital lobe
25:27thanks to the parietal occipital sulcus
25:30thanks to the parietal occipital sulcus
25:34next then we've got the occipital lobe
25:36you can appreciate at the most dorsal
25:38aspect there then
25:39of the cerebral hemispheres and here
25:41coming out
25:42laterally you've got the temporal lobe
25:45now the temporal lobe
25:46you've got the lateral sulcus in
25:48relation to the temporal lobe this
25:49lateral sulcus is going to be found
25:50separating this
25:51temporal lobe from the frontal lobe and
25:54this
25:55parietal lobe so it separates
25:58frontal and parietal lobes from that
26:03temporal lobe
26:06then the fifth lobe is the insula in
26:08order to appreciate the insula
26:10we're going to have to basically move
26:13all those
26:13various segments over and here you can
26:16see the insula is going to be found
26:18buried deep within that lateral
26:21sulcus so buried deep within
26:25the lateral sulcus and it's going to
26:28form
26:30part of the floor it forms you can see
26:32there part of the floor
26:38let's go through and let's look at the
26:39cortices let's talk about the cerebral
26:41cortices
26:42so we talk cerebral cortices moving back
26:45to this diagram here we can appreciate
26:47again
26:48all of this outer bark region is
26:50basically
26:51uh what it's described as uh looking
26:54like or similar to so that's what we're
26:56going to go through we're going to check
26:57out we're going to look at now
26:58the cortices now the cerebral cortices i
27:01want you to know
27:03very important region here that's what
27:04we're going to go through we're going to
27:05talk about it the cerebral cortices
27:07they enable us to be aware of ourselves
27:11they're going to allow us to be aware of
27:13ourselves
27:15our sensations our sensations
27:21they're going to allow us to communicate
27:25the cortices will allow us to
27:27communicate remember
27:32understand
27:35and initiate voluntary movements and
27:39initiate voluntary movements
27:44now the cerebral cortex is composed of
27:46gray matter
27:47it's composed of gray matter neurons
27:50cell bodies
27:54dendrites
27:59glial cells
28:02and blood vessels
28:06no fiber tracts no
28:10fiber tracts
28:14let's first discuss the motor areas
28:18so the cortices that are responsible for
28:22motor innervation now we talk motor
28:24areas
28:25they're going to control voluntary
28:26movements so we talk motor areas first
28:28you have what we call the primary motor
28:30cortex
28:31so here we can appreciate now from this
28:33view here the primary motor cortex now
28:36we talk primary motor cortex
28:38primary motor cortex is going to be
28:39found located on the pre-central
28:41gyrus of each hemisphere in the frontal
28:44lobe
28:45so primary motor cortex located on the
28:48pre
28:49central gyrus of each hemisphere in the
28:52frontal lobe
28:54function function of the primary cortex
28:58of the primary motor cortex so right
28:59inside here you can see the function of
29:00the primary motor cortex
29:02is going to be that it consciously
29:05controls
29:07precise it will consciously control
29:09precise
29:10or skilled voluntary movements
29:14of our skeletal muscles
29:18we have pyramidal cells here these
29:21pyramidal cells are large
29:24neurons
29:26they're large neurons
29:29whose fibers are going to leave the
29:32cortex
29:35and connect to other parts of the cns
29:44then we have the term somatotropy there
29:46basically there we're talking about
29:48how different uh uh body
29:51basically regions we have been mapped
29:54out so basically when we talk
29:55somatotrophy it's talking about the
29:56mapping out of
29:58the body in the cns structures
30:01so for example we're going to see which
30:03part of the
30:05cortex is going to be responsible for
30:07providing innervation motor innervation
30:09to the foot
30:10to the elbow to the face
30:14okay so here you can see we've got the
30:16monopolist
30:17that goes through and depicts that here
30:20very well for us
30:21so you've got to be able to understand
30:23now if there's an injury to this area
30:25here
30:26these parts of the body
30:30are going to have motor innervation
30:32being affected there
30:34and as you progress out laterally you
30:36can see the different parts of the body
30:38that these different parts of the brain
30:39are going to control
30:43next then we've got the pre-motor cortex
30:45now when we talk
30:46pre-motor cortex you can see
30:50the pre-motor cortex now the pre-motor
30:53cortex is going to be found located
30:55anterior to the pre-central gyrus
30:58anterior to the pre-central gyrus
31:04or you can see anterior to the primary
31:06motor cortex it's the same exact thing
31:08there
31:09in the frontal lobe in the frontal lobe
31:13now the functions the functions of this
31:14premotor cortex i'd like you to know
31:16about now
31:17are going to be that it controls it
31:19controls
31:20learned motor skills
31:24of a repetitious or patterned nature
31:29such as playing a musical instrument
31:34or typing
31:37dancing even
31:40where
31:44the coordination of several muscle
31:48groups is going to be required
31:49so it coordinates the movement of
31:51several muscle groups
31:56next we can appreciate broca's area when
31:58we talk broca's area broca's area
32:00is present in the left hemisphere only
32:02it's present in the left hemisphere only
32:06it's found lying anterior to the
32:09inferior region
32:12of the pre-motor area anterior to
32:16the inferior region of the pre-motor
32:18area its function then
32:20the function of broca's area is that it
32:22directs the muscles involved
32:25in speech production
32:32next thing we have our frontal eye field
32:35when we talk about the frontal eye
32:37field the frontal eye field is located
32:41partially in and anterior to
32:45the pre-motor cortex partially
32:50anterior to the pre-motor cortex
32:54and superior to broca's area and
32:58superior to broca's area
33:01so here you can appreciate in red
33:05the frontal eye field
33:08now we talk frontal eye field functions
33:11it controls voluntary movements
33:14of the eyes it will control voluntary
33:17movements of the eyes
33:20so controls voluntary movement of the
33:23eyes
33:26so those are our motor areas as you can
33:28see they're being depicted in red
33:29let's move them to the sensory areas now
33:32the sensory areas are going to be
33:34concerned with
33:35conscious awareness of sensation they
33:38will be concerned with conscious
33:39awareness of sensation
33:42so it's going to be the dark and the
33:43light blue areas let's talk first the
33:45primary somatosensory cortex
33:47when we talk primary somatosensory
33:49cortex it's going to be found
33:51located in the post-central gyrus
33:55so it's found located in the
33:57post-central gyrus
33:59of the parietal lobe found located in
34:02the post-central gyrus of the parietal
34:03lobe
34:05posterior to the primary motor cortex
34:08posterior to the primary motor cortex
34:14now we talk function the function we'll
34:17see
34:18you can see primary somatosensory cortex
34:21so when we talk function
34:23function is going to be that it receives
34:25information
34:27it receives information from the general
34:30sensory receptors it receives
34:34sensory information
34:37so it's receiving information from the
34:39general sensory receptors
34:41in the skin
34:46and from proprio receptors
34:50and also from proprio receptors these
34:52are gonna be receptors that are found in
34:53relation to your
34:54skeletal muscle to your joints
34:59and to your tendons
35:04so all this information is going to make
35:06its way then
35:07to our primary somatosensory cortex
35:11so it receives information from our
35:13general sensory receptors
35:15that are found located throughout the
35:16skin and also from our proprio receptors
35:20then again somatotrophy we've got here
35:22as well so just like we saw with motor
35:24innervation we've got the same thing
35:25happening with sensory innervation
35:27and you can see that homonculus right
35:29inside of there
35:31same thing you can see here
35:34again the same thing you can see there
35:36as well i just like these
35:38images a little bit better so i've kept
35:39them there
35:41same thing here as well so sensation you
35:43can see to all the different areas
35:45starting with this area that's just uh
35:48you can see within that longitudinal
35:50fissure you've got it controlling the
35:51genitals all the way to the feet
35:53and then coming around the ankles and
35:55you can see making your way around
35:58laterally now you can see the different
36:00uh parts of the body being
36:01basically a responsible sending sensory
36:04information to that part of the brain
36:09so let's move to then your somatosensory
36:12association cortex
36:14to the somatosensory association cortex
36:18now when we talk somatosensory
36:19association cortex
36:21it's found lying it's found lying
36:23posterior to the primary somatosensory
36:26cortex
36:27it's found lying posterior to the
36:30primary somatosensory cortex that we
36:32just talked about so
36:33right back here you can see the
36:35somatosensory association cortex
36:38now we talk somatosensory association
36:40cortex its function
36:41its function is to integrate sensory
36:43input
36:45it will integrate sensory input
36:46basically temperature and pressures
36:49to produce an understanding then
36:53it integrates sensory inputs to produce
36:57an understanding
37:00even if you stick your hands in your
37:01pocket you say okay here
37:03uh sensory receptors are giving you this
37:05information okay here i've got
37:06chapstick here are my keys here's a dime
37:10here's a quarter
37:11you know here's a dollar bill uh you
37:14know i don't know is it five a 20 or
37:15that i mean we're not that good with but
37:17at least we know this is money or
37:18you know maybe even regular paper you
37:21could confuse it for
37:22uh there as well so again the
37:24somatosensor the somatosensory
37:26association cortex
37:27is going to integrate sensory inputs to
37:29help produce then an understanding
37:34so it integrates uh basically this
37:37information from the objects
37:38that are being felt or seen or
37:41temperature being sensed
37:42and then it helps to produce that
37:44understanding
37:46next thing we have our primary visual
37:48cortex now our primary
37:50visual cortex is going to be found
37:52located at the extreme posterior tip
37:54of the occipital lobe at the extreme
37:57posterior tip of the occipital lobe
38:04so at the extreme posterior tip of the
38:06occipital lobe
38:07and here you can see that right inside
38:10of here
38:12i'm going to move over to another view
38:14this other view is going to be basically
38:15a nice
38:16medial cut along that longitudinal
38:19fissure and you're going to be able to
38:20see this
38:21here very well so this parasagital
38:25view we can say here you can see the
38:27rest of that primary visual cortex
38:29so when we talk primary visual cortex i
38:31told you it's at the extreme posterior
38:32tip of the occipital lobe
38:34but most of it is going to be buried
38:37deep in the calcarine sulcus
38:42so it's buried deep in that calcarine
38:45sulcus
38:47in the medial of
38:50in the medial aspect of that occipital
38:52lobe
38:54so on that medial aspect of the
38:56occipital lobe
39:01so again extreme posterior tip of the
39:03occipital lobe but most of it is buried
39:05deep in that calcrine sulcus
39:07in the medial aspect of that occipital
39:12lobe
39:17another function let's talk function
39:19function of this primary visual cortex
39:21so coming back out
39:22you can see primary visual cortex right
39:24inside of there again
39:26and then you can see the majority of it
39:28is buried deep within that calcium
39:29sulcus
39:30so it receives visual information
39:33that originates on the retina of the eye
39:36it receives visual information
39:40that originates on the retina of the eye
39:47next then we have our visual association
39:49area so moving back
39:50out you can appreciate the visual
39:52association area there as well
39:54moving back out you can see our visual
39:56association area
39:58it's found surrounding the primary
40:00visual
40:01cortex it is found surrounding the
40:04primary visual cortex
40:06and covers most of that occipital lobe
40:09as you can see
40:10and it covers most of that occipital
40:13lobe
40:14when we talk function we talk function
40:17you'll see
40:18it's going to use past
40:21visual experiences it will use
40:25past visual experiences to interpret
40:28visual stimuli
40:32enabling us then to recognize what we
40:35are seeing
40:37enabling us to recognize what we are
40:38seeing
40:43next we can appreciate the primary
40:45auditory cortex
40:47the primary auditory cortex now we talk
40:49primary auditory cortex
40:51the primary auditory cortex is going to
40:53be found located at the superior margin
40:56of the temporal lobe
40:58at the superior margin of the temporal
40:59lobe you can see that there very nicely
41:02and they say it's a budding right next
41:04to
41:05a budding or a a budding or right next
41:08to
41:11a b u t t i n g a butting
41:17or right next to the lateral sulcus
41:21the function of the primary auditory
41:22cortex you'll see its function now
41:25is that it interprets sound for pitch
41:29it will interpret sound for pitch
41:34loudness and
41:37location loudness
41:41and location
41:46and then you can see right next to it uh
41:49is the auditory association area
41:51so we talk a auditory association area
41:54this
41:55auditory association area is going to be
41:56found posterior to the primary auditory
41:59cortex
41:59so just posterior to so you can think
42:01lateral and posterior to
42:04the primary auditory cortex
42:07now the auditory association area it
42:10permits the perception of
42:12sound stimulus as speech
42:18a scream
42:22and music or even music so it's going to
42:25permit
42:25the perception of sound stimuli
42:29as speech
42:32a scream or music being played
42:39this is where we store sound memories
42:41and this is where we store
42:43sound memories
42:47these association areas next we've got
42:51our primary olfactory cortex now we talk
42:53primary olfactory cortex
42:56it's involved with the sense of smell
42:57it's going to be found located on the
42:59medial aspect of the temporal lobe
43:02found located on the medial aspect of
43:04the temporal lobe
43:10on the piriform lobe they also refer to
43:13it as
43:14so we'll look at that in a few seconds
43:16now this primary olfactory cortex when
43:19you look at its shape
43:20you'll see it's got like a hook part to
43:23it it's got like this part that looks
43:24like a hook to it
43:26and it's called it's a little hook-like
43:29part that's called an
43:30ankus
43:34you can see that here very well so
43:37here's the primary olfactory cortex
43:39and then here's the unkiss the hook like
43:41part of it
43:42right inside of there
43:47function primary olfactory cortex its
43:49function is to give us
43:50conscious awareness of different odors
43:53it will give
43:54us conscious awareness of different
43:55odors
44:01next then we have the gustatory cortex
44:04and we talk gustatory cortex the
44:05gustatory cortex
44:07is when we talk location you'll see the
44:09gustatory cortex
44:11is in the insula deep
44:14to the temporal lobe so here you can see
44:18gustatory cortex
44:19in the insula deep to the temporal lobe
44:25function of the gustatory cortex
44:27function is that it's involved
44:29in the perception of taste stimuli
44:32it is involved in the perception of
44:35taste
44:36stimuli
44:41next time we've got our visceral sensory
44:43area
44:44now our visceral sensory area you can't
44:46see so when you talk location
44:48i'll tell you location location is going
44:50to be the cortex of the
44:52insula
44:55cortex of the insula
44:58posterior to the gustatory cortex
45:02you can't actually see it but it's
45:04described as being
45:05at the cortex of the insula posterior to
45:08the gustatory cortex
45:12when we talk function function of this
45:15visceral sensory area
45:17is it's involved in the perception of
45:19visceral sensations
45:20it is involved in the perception of
45:22visceral sensations
45:26upset stomach full bladder let's say for
45:30example
45:32all thanks to then this visceral sensory
45:34area
45:38next we have our vestibular cortex then
45:41we talk vestibular cortex vestibular
45:43cortex you'll see is going to be
45:44involved in maintaining equilibrium
45:47maintaining equilibrium
45:50so when we talk vestibular cortex the
45:53vestibular cortex
45:55the location again unknown exact
45:58location
45:59unknown exact location
46:02can't see it however we believe it's
46:04posterior
46:05it's at the posterior part of the insula
46:07it's at the posterior part of the insula
46:11and adjacent to the parietal cortex
46:15and adjacent to the parietal cortex
46:19when we talk function function you'll
46:22see
46:22it's going to be involved in the
46:24awareness of balance
46:26it's involved in the awareness of
46:28balance
46:30and the position of the head in space
46:34and the position of our head in space
46:44next then we have our multimodal
46:46association areas
46:48now when we talk about our multimodal
46:50association areas
46:52i'd like you to know there's a couple of
46:54different uh
46:56parts here we're gonna go through we're
46:57gonna look at first we have what we call
46:59the anterior association area
47:01the anterior association area is also
47:04known as the
47:05prefrontal cortex again prefrontal
47:08cortex
47:08remember we're still talking about the
47:09corteses so the prefrontal cortex you
47:12can appreciate here
47:13then in pink purple pink
47:17pink i think yeah i guess this is like
47:20that
47:21gold dress or shoe or whatever it was
47:24and
47:25they know the color or even the object
47:27so forget that or a black dress or
47:29whatever it was there
47:30so you can appreciate the anterior
47:32association area here then or
47:34prefrontal cortex we also refer to it as
47:36now again the location
47:38on the frontal lobe now when you talk
47:40function
47:41function is that it's involved with
47:43intellect
47:45it's involved with intellect complex
47:48learning abilities
47:53recall our ability to recall
47:58and personality and personality
48:08next then is the posterior association
48:10area now you can look at the posterior
48:11association area
48:13and you can appreciate that right back
48:14here is the same color there now as well
48:16as the anterior association area
48:18when we talk posterior association area
48:20it's a large region
48:22encompassing you can see the temporal
48:24lobe
48:25parietal lobe and parts of the occipital
48:27lobe
48:30function function of this posterior
48:32association area
48:34is that it recognizes patterns and faces
48:37it recognizes patterns and faces
48:41localizing us and our surroundings
48:44localizing us and our surroundings
48:53now wernicke's area just like broca's
48:56area
48:57are found on the left hemisphere only
49:00both
49:01only present on the left hemisphere so
49:03we talk wernicke's area
49:05wernicke's area is involved in
49:08understanding
49:13or you can say it's involved in the
49:14recognition
49:18of written and spoken language so it's
49:21involved in
49:22understanding written and spoken
49:28language
49:34i can't see myself when i'm recording so
49:37i don't know you know what i look like
49:39or what's going on i find out afterwards
49:42sorry
49:47i don't know lighting or anything i
49:48tried to fix it the best i could before
49:50i started but
49:52we'll see afterwards so wernicke's area
49:55present on the left hemisphere only just
49:57like we said with broca's area as well
49:59okay so next let's move down let's talk
50:01uh limbic association area
50:03let's talk olympic association area so
50:05here then we can move
50:06and again look at this is all we've
50:08talked about is the cortices so you see
50:09just that outer border
50:10highlighted there same thing here as
50:12well
50:16limbic system let's talk limbic
50:18association system so here
50:20uh olympic association area now when we
50:21talk olympic association area it's going
50:23to include
50:24a few structures so it's going to
50:25include the cingulate gyrus
50:27it will include the cingulate gyrus
50:29it'll include the
50:30amygdala the amygdala and the
50:33hippocampus
50:34so the prominent components making up
50:36this limbic system are going to be the
50:38amygdala
50:39cingulate gyrus and the hippocampus
50:44now the function the function is it's
50:45involved with emotion and memory
50:47it's involved with emotion and memory
50:51okay you can say kind of it provides us
50:53with the emotional impact
50:55that makes a scene important to us
50:59so emotion and memory
51:02we had the term ipsilateralization that
51:04we used before
51:05now the term lateralization is there now
51:07when we talk lateralization
51:10and contralateralization basically it's
51:12going into and it's talking about how
51:14some parts of the body their function is
51:17going to be controlled by
51:19the same side brain
51:22or sometimes when we talk
51:23contralateralization you'll see
51:25the right side brain will control parts
51:26on the left side so that's basically
51:28what these two terms there are in
51:29reference to
51:30next then let's move down to white
51:33matter cerebral white matter
51:34and we talk cerebral white matter it's
51:36going to consist mainly of myelinated
51:38fibers mainly of myelinated fibers so
51:40here's a
51:41good view depicting that to us there and
51:44we can see the same thing right inside
51:45of here besides beta nuclei
51:48and same thing we can see here now when
51:50we talk
51:51cerebral white matter its function is
51:53that it's involved
51:54it's responsible for communication it's
51:57responsible for communication between
52:00cerebral areas and between
52:03the cerebral cortex
52:07and lower cns structures so responsible
52:10for communication between
52:12cerebral areas and
52:15between the cerebral cortex and lower
52:17cns centers
52:21here you have commissures i want you to
52:23be familiar with them we talk common
52:24shores
52:25common shores are going to be basically
52:27helping to connect
52:29corresponding gray areas of the two
52:32hemispheres
52:34they help connect corresponding gray
52:38areas of the two hemispheres
52:41enabling them to function as a
52:43coordinated whole
52:45enabling them to function as a
52:47coordinated whole
52:49there is a couple of different types of
52:51commissures that you'll have to know
52:53about the first type are going to be
52:54is going to be your corpus callosum now
52:56we talked corpus callosum here you can
52:58appreciate the corpus callosum
53:00from this view here where they've done
53:02uh basically
53:04you can see there a nice coronal cut and
53:07through this coronal cut now you can
53:09appreciate those commissural fibers
53:10but in order to appreciate this
53:12commissure in greater detail what we can
53:14do is we can move over to this picture
53:16right inside of
53:17here you can see that corpus callosum
53:20right inside of there
53:23so look at this image versus this image
53:26this detailed image of those fibers
53:32so corpus callosum it's the largest
53:34commissure
53:36located superior to the lateral
53:40ventricle
53:42located superior to the lateral
53:44ventricles
53:46and deep in the longitudinal fissure
53:50and deep in the longitudinal fissure
53:54we also have anterior and posterior
53:57commissures
53:59here we're going to be able to
54:00appreciate then the anterior
54:02and posterior commissures here we've got
54:04the anterior commissure again
54:06connecting corresponding gray areas of
54:08the two hemispheres
54:10here we've got the posterior commissures
54:15right inside of there
54:19and they're less prominent chroma less
54:21prominent commissures compared to that
54:22corpus callosum
54:26next i'll move back to this image and we
54:28can see the association fibers
54:31and we talk association fibers now the
54:33association fibers are going to connect
54:35different parts of the same hemispheres
54:38so here you can see in that pink
54:40or bright kind of a pink you can see
54:44all of these various association fibers
54:46so again these association fibers
54:48they're going to connect different parts
54:50of the same hemispheres
54:51some are long and some are going to be
54:53short but they connect different parts
54:55of the same hemisphere
54:58then you have your projection fibers
55:00when we talk projection fibers the
55:01projection fibers are going to be
55:03sending
55:04sensory information to the cerebral
55:06cortex
55:07they'll send sensory information to the
55:09cerebral cortex
55:12and they take motor output and
55:16take motor output
55:20so here you can appreciate those
55:22association fibers
55:24uh we saw here and now here are the
55:26projection fibers
55:28all projection fibers up this way and up
55:32this way here now in relation to these
55:34projection fibers you've got a couple of
55:36divisions or a couple structures in
55:37relation to them
55:38first you've got the internal capsule
55:40now the internal capsule you can
55:41appreciate
55:42right inside of here and right inside of
55:44here basically it's a
55:46it's a it's a collection or a compact
55:49band of
55:49projection fibers it's a collection of
55:52projection fibers
55:54found at the top of the brain stem found
55:57right at the top of the brain stem so
55:59you can see here you've got the medulla
56:00you've got the pawns and then we're
56:01going to have the midbrain
56:03and then right up here commissures
56:09you're going to have the peduncles the
56:10cerebellar peduncles and then right
56:12inside of here if we're
56:13moving a little bit more anterior right
56:15and then here you can appreciate
56:18the internal capsules and then here as
56:20you continue up
56:22further into the cortices you can
56:24appreciate this
56:25fan like radiating
56:30fan like radiating pattern
56:33of these projection fibers that's the
56:35corona
56:36radiati the corona radiati
56:40so the fan like fibers radiating through
56:43the cerebral white
56:44matter to reach the cortex
56:48next then we have our basal nuclei we
56:50talk basal nuclei basal nuclei are going
56:52to be
56:53masses of cereb masses of cerebral gray
56:56matter
56:57masses of cerebral gray matter
57:01embedded deep in the white matter
57:03embedded deep in the white matter
57:06so first we have the corpus triatum we
57:08talk corpus striatum corpus striatum
57:10it's consists of the lentiform nucleus
57:13and the caudate
57:14nucleus
57:18let's talk caudate nucleus caudate
57:20nucleus then you can appreciate
57:23just inferior to the lateral ventricles
57:25bilaterally on both sides
57:29and then we've got the lentiform nucleus
57:31the lentiform nucleus you can see
57:32inferior to that caudate nucleus on both
57:35sides
57:36it's made up of the putamen and the
57:38globus pallidus
57:40the putamen and the globus pallidus
57:43putamen and globus pallidus
57:46now the function of this whole basal
57:48nuclei
57:49the whole function of the basal nuclei
57:52is that it influences muscle movement
57:55influences muscle movement so motor
57:57control
57:59and it helps to regulate attention and
58:02cognition
58:04it helps to regulate attention and
58:07cognition
58:12it's also going to regulate
58:15the intensity of slow or stereotyped
58:20movements
58:23and it inhibits antagonistic
58:28and unnecessary movements and it will
58:31help
58:31inhibit antagonistic and unnecessary
58:35movements
58:40so this will conclude then this first
58:43part of chapter 15 and the last part of
58:4613 there
59:00you

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