MARIAN DIAMOND: Good morning.
It's quite loud this
morning, excuse me--
sort of shocked myself too.
Let's continue with our
derivatives of the neural tube.
And we were talking
about the mesencephalon,
but we didn't quite complete it.
So I'd like to return to it.
And we drew a section
through the mesencephalon.
We showed the aqueduct was here.
This is our central canal as
it looks-- boy, this is loud.
Is that loud for you too?
STUDENT: [INAUDIBLE]
MARIAN DIAMOND: Right,
it keeps you awake.
STUDENT: [INAUDIBLE]
MARIAN DIAMOND: It's what?
It's OK.
All right, thanks.
Aqueduct-- and
then, we had the--
these could be the corpora
quadrigemina-- either.
I just repeat it,
repeat it, repeat it.
And sometimes, that's
referred to as the tectum.
Tectum means roof.
And you'll see that
in the literature too,
so I thought this
morning I'd put it in.
Tectum is the same
as a roof here.
Then, we had that
cerebral peduncles
down on the ventral surface.
And we put in the
substantia nigra,
which would be just
dorsal to the peduncles.
This would be the
substantia nigra.
And we said it gets its
name, black substance,
from the pigment melanin--
pigment melanin.
And the fibers were
rich in dopamine.
Dopamine was their transmitter.
And there's substantia
nigra projects
then up to the basal ganglia.
We'll see the basal
ganglia today.
We'll develop it--
basal ganglia,
which modifies motor behavior.
Does many things but just for
the moment, we need this--
modifies motor-- we'll
just say motor action--
so that if we get
[INAUDIBLE] that
knocks out our substantia nigra.
So lose cells in
substantia nigra,
what disease did we say you got?
Everybody knows that one.
It's such a clear cut one.
Parkinson's, and the
tremor for Parkinson's is
a tremor at rest.
And I give you that
one because there's
another part of the
brain that gets destroyed
and it's a tremor when you
intend to do something.
So [INAUDIBLE] when you
look at your neurosurgeon,
whether he's trembling at rest,
because then you know he'll
go away when he starts
to do his surgery.
But the intention tremor can
be sitting there quietly.
But when he picks up the
scalpel, then he does that.
So you have to be careful.
So let's move on up then.
There are lots more
things in our--
one other thing I do
want to say though,
because I want to
be consistent here.
We've been giving
the cranial nerves
with each one of these areas
as we move up the brain stem.
So the cranial nerves
with the mesencephalon
will be three and four.
And the ventricle then
was our aqueduct so--
to see how they
change as we go up.
So our next area will
be the diencephalon,
as we move up from
the mesencepholan.
Our diencephalon--
and we might as well
give the cranial nerve
associated with it,
since we just talking about it.
What cranial nerve is
related to the dyancephlona.
Well, we've moved
all the way up.
We've only got two more to go.
We've gone from 12
up to three, so where
are we with nyancelphlaon?
Two.
And what is the
second cranial nerve?
Does anybody know?
It's the optic nerve,
very important.
Yours is definitely
being used right now.
And the ventricle
in the dyancelphloan
then is going to
be what ventricle?
We've had fourth.
We've had aqueduct.
We're moving up.
What's next-- third.
So just so you can figure
these things out for yourself.
So it's not just memorizing.
You could see where you are.
So we're going to have
a third ventricle.
And the structures that we'll be
dealing with then will be the--
I've got to take this
off, I trust you have it--
thalamus and epithalamus
and hypothalamus.
But I first want to make
one point, because it gives
a landmark that's
used when you're
using radiology and finding out
where your sections are coming
from.
So I'm going to make our
old neural tube that we had.
This is our neural tube.
And the most anterior
part of the neural tube
is called the
lamina terminalice.
Lamina-- which
just means layer--
terminalus, because we want
to use this landmark when
we put it in our
diencephalic structures.
So this is going to be
our lamina terminalis
for a lateral view
of our diencephalon.
This is our lamina terminalice--
an important structure for a
landmark when you're reading
scans.
So from it, we're going to come
out and form the structures
of the diencephalon.
And what we've put here
will have three structures.
We'll have the epithalamus.
Epi means a upon, so it
means upon the thalamus.
So the epithalamus is just going
to be some structures up on top
here.
But in addition, the
pineal gland back here.
So our epithalamus
will be this, and this
will be our pineal gland.
It's the only structure
of the epithalamus
that I'm going to give you.
It is what?
It's a neuroendocrine gland--
neuroendocrine.
It plays a role in
establishing and maintaining
your biological rhythm--
your biological,
or biological clock
if you like-- biological clock.
Don't you find it
strange that after you've
gotten up at 6 o'clock in the
morning for several months
and had your alarm, sometimes
your alarm doesn't go off,
but you get up anyhow?
Your pineal is playing a role.
So beneath the epithalamus,
we have the thalamus.
What is the thalamus?
The thalamus is
a mass of nuclei.
We defined nuclei before.
Whoops, there it goes.
What happened?
Thalamus-- mass of nuclei.
And somebody said they're
about 25, plus or minus.
We're not going to
give you those, just
let you know that they exist.
All sensory impulses that are
going to your cerebral cortex
first go through the thalamus
before they go to the cortex,
with one exception.
So all sensory input
goes through thalamus
before going to cerebral cortex.
But there's one
sensation that does not.
What is that?
STUDENT: Olfaction.
MARIAN DIAMOND:
Olfaction, right--
that's a course in itself.
Why doesn't olfaction?
So for example--
just making it easy--
we're going to bring light to
the retina, to the thalamus,
to the visual cortex.
And one could do this
with all, but you'll
find out that the auditory
pathway is much more complex.
So it's not just from
the main receptor
to the thalamus to the cortex.
So I picked light instead.
So that gives you a general
idea of the thalamus.
What does it look like?
They're considered
to be egg-shaped.
You have the two thalami,
the right and the left.
And the third ventricle
then will be between them,
with the hypothalamus below.
And then go on down to
your pituitary here.
So these would be
thalamus, thalamus.
And the third ventricle
will be between them here.
And this will be hypothalamus
in this slide, in this section.
And here's to pitiatary.
Just to give you, this
would be a coronal view.
In some, there's a connection
between the two thalami.
Does anybody know
what it's called?
The massa intermedia,
massa intermedia.
It's missing in 30% of males.
And we've tested that once in
class when we had 20 brains.
We knew what sex they were.
Exactly 30% were missing it.
Males as you know, if we
could go into sex differences
in the brain-- whole subject--
are more lateralized.
That means, many
times, they have
one side that's much stronger.
The right side
stronger than the left.
And perhaps those
people who have this
don't have that differentiation.
But when it's missing,
they have it strongly.
I don't know.
Now, the structure beneath the
thalamus is the hypothalamus.
And this, many of us, when we
were starting in the field,
thought was the most exciting
structure in the brain.
How much does it weigh,
your hypothalamus?
Hypothalamus weighs
only four grams.
How much does a
large grape weigh?
Four grams gives
you the size of it.
I know.
It depends on the size
of the grape, but still.
What are the functions of
this important structure?
Why did it attract so many of
us, when I did my PhD on it?
Well, number one,
it's a control center
for your autonomic
nervous system,
control center for the A and
S, which we've introduced.
It regulates your
body temperature,
regulates body temperature.
How many have an average
body temperature of 98.6?
How many don't?
How many know what your
average temperature is?
But how in the world?
You put all these different
kinds of fuels in there,
and this machine can maintain
a body temperature, because you
have a hypothalamus.
You destroy this nucleus
in the hypothalamus.
The hypothalamus,
again, is a mass
of nuclei, just
like the thalamus
but only different functions.
If we destroy the
nucleus for temperature,
temperature will climb
to 106 and death.
Then, we have anterior
pituitary releasing hormones.
This is our pituitary down here.
So hypothalamus can
send down releasing
hormones, anterior
pituitary-releasing hormones.
It regulates thirst.
You finish class, you run
out and get a drink of water.
It regulates your appetite,
tells you when you want to eat.
It affects emotions.
Just think, a
computation that has
to go on to a little
structure that's that big.
We're still going.
It affects mating behavior.
It's actually different
in homosexual males
than heterosexual
males in the one area
dealing with mating behavior.
So seven affects
mating behavior.
And it affects your
sleep mechanism.
Where are we-- nine, memory.
And it produces your
posterior pituitary hormones.
Produces-- just, we'll
put it produces--
ADHD, which is
antidiuretic hormone
to be stored in the
posterior pituitary.
That was my thesis, to see if it
was active in the hypothalamus,
as well as in the pituitary.
And it was.
But look at that.
Isn't that amazing?
You know how you tell somebody
where your hypothalamus is--
that's exactly it.
He knows exactly-- up
your nose, above your ear,
where the two points meet--
because most people have
never heard of a hypothalamus.
But look at what
it does for you--
phenomenal.
So let's then go on
to our telencephalon.
Can I take this off?
So we're way up at the top--
telencephalon.
The telencephalon than
is going to account
for 85% of your brain.
It's the big
[INAUDIBLE] and will
consist of the basal ganglia
and the cerebral hemispheres.
These are the
massive hemispheres.
So we've worked our
way all the way up.
When we're drawing
embryologically,
here would be our
lamina terminalis
from our neural tube.
But then, we pouch
out like this to start
to form our cerebral
hemispheres and basal ganglia.
This was our lamina terminalis.
So that landmark is
used a great deal
in talking about
forebrain relationships.
So let's look at the
embryo, at the reason why
it's called a basal ganglia.
Let's look at our hemispheres.
And this will be in the embryo.
And have the [INAUDIBLE]
till we get to the base.
And then, we'll come in.
So here, in the base
of the hemispheres,
we will have these
masses of cells
that are the precursors of
your adult basal ganglia--
basal ganglia.
And these, of course, are
your cerebral hemispheres.
And so what will we name
or number the ventricles
in the cerebral
hemispheres way back
at this level-- one and two.
As we get to the adult, we call
them the lateral ventricles.
One and two will become
lateral ventricles.
And those are going to be
reading MRIs and PET scans,
you'll have to know your
ventricles backwards
and forwards, because
they're affected.
If you've got a tumor,
they get smaller.
If you get older,
they get larger,
as the cortex decreases.
So ventricles in your
medical profession
are very important to know.
But what do they look like
now in the adult brain?
Let's take a section
through an adult brain.
So we'll take our
hemispheres again.
And we know we have the
thalamus in here, the thalamus.
And we have a hypothalamus
beneath it in here,
coming on down just to
get our orientation.
What's the ventricle
between the thalami?
Third-- very important.
Third ventricle.
Hypothalamus has the same third
ventricle, because they're
both right together.
So it just lets you know what
we have in our midline area
at this level.
But now, we're going to
put in the basal ganglia.
They take on a very
different shape in the adult.
And we're going to put in
some lateral ventricle here.
So this will be a lateral
ventricle at this level.
And we'll put in some
more basal ganglia here,
inferior to the lateral wall,
or the lateral ventricle.
Got the same duplicated
on the opposite side.
We need one more structure.
It will be in here.
So we're ready to label
these now basic parts
of the basal ganglia--
so parts of basal ganglia.
Let's take number one.
One is the caudate
nucleus, chordate nucleus.
We'll show pictures of these.
Number two, we're going
to take the lateral aspect
of this part, and this
is called the putamen--
putamen.
And the medial part
here has divisions,
but we're just going
to show it as a whole
for introductory purposes.
It's called the globus pallidus.
These will be
second nature to you
after you start studying brains.
What does that mean?
Pale globe-- so you'll
be able to pick it out
because it stains much
lighter than the putamen
or the caudate, for example.
And our fourth one here--
I should have had a
little bigger thalamus--
so it's called the subthalamic
nucleus, sub thalamic nucleus.
So one, two, three, four
equal our basal ganglia--
very large, very important
part of your forebrain,
modifying motor behavior.
You get different symptoms
from every one of these.
If you knock out your
subthalamic nucleus,
I've only seen one example
in my life of subthalamic.
And he goes like this.
He was an engineer.
He could talk to
you, he was fine.
But he had no control
over these flailing limbs.
Just amazing-- so you better
be thankful that you're
subthalamic nuclei are in order,
because I don't see anybody
going through such gyrations.
But it was amazing
and fatiguing too.
So just to let you
know the importance
of these when they work.
You just take them for granted.
So what else would we want to
say about our basal ganglia
before we move up?
Let's be sure we're catching it.
Yes, we want to mention another
important structure here.
Let's put in the internal
capsule, internal capsule.
So we're going to see a pathway,
fibers that are surrounding
the basal ganglia.
These x's make up
the internal capsule.
And you say well, is
there an external?
Yes, but not as much
is known about it,
but I'll put it in out here.
This will be external capsule.
But the internal is
extremely important
because we've put
these basal ganglia
right in the middle
of our hemispheres
where we have all this
information coming
from the thalamus, coming
from the spinal cord,
into the cortex.
And it's got to go
around these big nuclei.
So they call the inner
one the internal capsule.
So it consists of ascending
and descending fibers
to and from cerebral cortex.
So if I break a blood
vessel right in here,
we know exactly what fibers
will be knocked out coming
from my motor behavior.
These are very well-defined
within the internal capsule.
All right, that gives us one
component of our telencephalon.
And our next one then are these
large cerebral hemispheres,
which make you you and me
me, give us our uniqueness
to our brains.
So cerebral
hemispheres-- so we're
going to divide these into
the archicortex, which
means the old cortex,
and the neocortex.
Let's take the
archicortex first.
It will only have three
layers in its components.
And what are they?
They're found in what's known
as the hippocampal complex,
hippocampal complex.
What does that consist of?
It consists of the hippocampus
and the dentate gyrus,
dentate gyrus.
We've used this
term before when we
said that there
were neurogenesis
or new nerve cells can
be formed in the adult,
in the dentate gyrus,
because it had granule cells
with small, short axons.
So where is this
hippocampal complex?
Let's put it in and then say
a word about its function.
So let's take a medial
view of the hemispheres.
Just to put in some landmarks,
when we cut through the two
hemispheres, we'll have
a big mass of fibers
that we've cut through, that are
connecting the two hemispheres.
Who can tell me what
they're called--
the corpus callosum.
So this is the corpus callosum.
For those who haven't
studied neural before,
we'll look at them
a different way,
and we'll see that we've
got these fibers that
are connecting back and
forth to the hemispheres,
coming around and going here.
So it's crossing like this.
But what we've done,
we've cut in the middle.
So we've got them crossing
and looking at them
from a medial view.
So that's the corpus
callosum those are fibers
connecting both hemispheres.
All right, those for a landmark,
whenever you see those,
you know it's a medial view.
To pick up the
hippocampal complex,
we're going to go
into this lobe.
What is this lobe--
temporal, good for you.
Temporal lobe just beneath
your temporal bone.
You can figure these out.
This would be which
lobe up here--
frontal, sure.
So we want to go
deep into the lobe,
because it's not going
to be on the surface.
So deep within this
lobe, we'll find
this structure that
looks like a sea horse
to the early anatomists.
And this is the hippocampal
complex in here.
When you study neural, you'll
follow all of its pathways,
but we're just
identifying it here.
This is hippocampal complex.
And I'd have to peel
at a part so you
could see the dentate gyrus.
Why is it called dentate?
What does dentate mean?
Teeth, you look at it, and it's
just got all these little rows
like this.
And that's the dentate gyrus.
So it's easy to identify
when you have a brain
and can peel back
the hippocampus.
What does a
hippocampus do for you?
Hopefully, it's working in
your brains at this moment.
What's it doing?
STUDENT: [INAUDIBLE]
MARIAN DIAMOND:
What kind of memory?
There are all sorts.
STUDENT: [INAUDIBLE]
MARIAN DIAMOND: Pardon.
STUDENT: [INAUDIBLE]
MARIAN DIAMOND: Short-term
memory, right, thank you.
So this complex deals with
short-term memory processing--
terribly important.
And what's another function
for the hippocampus--
visual spatial acuity,
visual spatial acuity.
So when is it important?
Let's say you're going on
a trip for three weeks.
You park your car in the
parking lot down in the Oakland
Airport, and you've got to
remember where you parked it.
So as you leave it,
you turn around,
reinforce your visual
spatial acuity,
so you know exactly where it is.
So when you're coming
from the other direction,
you'll recognize where it is.
And you need your recent
memory to put it into long-term
memory--
so hippocampus, just
a small example.
It's very much affected
with Alzheimer's.
I saw in University of
Iowa, [? Dimassio ?]
said you want to see
a defunct hippocampus?
And I said, yes.
And he said he just has one
in from an Alzheimer patient.
So you looked under
the microscope,
and the cells were
all disoriented
and decreasing
for recent memory.
So you need to work on your
recent memory for a lifetime,
because otherwise, you lose it.
All right, so this
is the archicortex.
And as we said,
it's three-layered.
It's not as complex.
It's older.
But we go up to our
neocortex, which
is the most highly-evolved
mass on this Earth
and most recently designed.
It's the last to develop
embryologically and the last
to develop phylogenetically.
So we're up to our
cerebral hemispheres.
Let's look at a
lateral view again.
And as we showed you previously,
that it's thrown into folds.
How big did I say it would
be if it weren't folded?
[INTERPOSING VOICES]
Not the cerebral cortex.
No, that would really
be interesting,
because to fold that
as big as a cortex,
we'd have heads as big as this
center part of our auditorium.
So to have, it's as big as
two and 1/2 feet square.
And we always ask, why
can't you have a head that's
two and 1/2 feet square.
STUDENT: [INAUDIBLE]
MARIAN DIAMOND: Pardon.
STUDENT: [INAUDIBLE]
MARIAN DIAMOND: Well,
I think it's something
more important than that.
Pardon, why can't you have a
head two and 1/2 feet square.
Why does it have to
fold as it evolves?
STUDENT: Childbirth.
MARIAN DIAMOND:
Childbirth, of course.
You imagine, any woman
who's given birth
and knows two and
1/2 feet square.
That's not gonna work.
So it's highly folded,
and it's folded
so that you have these folds.
And the top of the
fold is called a gyrus.
And the indentation
between the folds--
these are gyri-- would
be sulci or a sulcus.
Some people like
hills and valleys.
The hills are the dry rye.
Anyway, just to remember
them, because when
you have Alzheimer's, the
sulci are very much pronounced
because the gyri have
been losing their cells.
So they're important to know.
And when we look at the lateral
aspect of our brain over here,
we have a central sulcus.
You have a lateral fissure--
lateral fissure.
So what lobe is this?
What lobe is this?
[INTERPOSING VOICES]
What lobe is this?
[INTERPOSING VOICES]
What lobe is it--
temporal.
So we've learned that the
occipital deals with vision,
all sorts of modifications.
Part of the temporal-- just
a little part up here--
deals with hearing.
The parietal deals
with sensory--
general sensory--
pain, touch pressure.
We'll just put sensory.
Lots of other functions
but just to give it a name.
And part of the frontal,
what's this first part
of the frontal deal with?
Motor but it's
really refined motor.
And then, we have what's
called supplementary motor.
We'll just give you one other
that you've already had.
What is here--
Broca's area, good for you.
What artery is
supplying Broca's area?
Middle cerebral,
don't forget it.
You heard the fellows at 131
using that the other day.
So this is Broca's area.
What does Broca's
area do for you?
[INTERPOSING VOICES]
Motor speech.
I wouldn't be able
to talk if I had
broken my middle
cerebral blood vessel.
Now, the area that
is uniquely human
and has advanced furthest in the
brain is our prefrontal cortex.
So let's say a word about
the prefrontal cortex.
So functions of
prefrontal cortex--
One, planning
ahead-- how many have
thought what they're going to
do on Thanksgiving vacation?
So you have a prefrontal cortex.
Two-- sequencing
events, knowing how
you're going to fit things
together to carry out
an action, sequencing events.
Initiative-- decide
what we're going to do.
And then, once you decide,
is it really wise to do it--
judgement from
prefrontal cortex.
Working memory-- how
does working memory
differ from others?
That you hold the
memory in your thoughts
while you're working with it.
I hold telencephalon.
What am I going to
bring in next to say?
That's working memory--
so working memory.
Oh, lots more--
lots, lots, more.
Let me just pull up a
couple just so that you
get the dynamics of them.
Oh, that's fine.
We'll do it with those.
Now, what game of cards
uses all of these functions?
Bridge-- yes.
That's why we use Bridge,
to see if we could stimulate
the prefrontal
cortex, because we
found in an
immune-deficient animal,
he was bilaterally deficient
in his dorsal lateral frontal
cortex.
We transplanted the
thymus, came back again.
We knew we had an area of
the cerebral cortex that
controls the immune system.
Whoops, we've got slides.
I didn't see the lights.
Did you see the lights?
Boy, I was involved-- sorry.
Here we go.
Can we go fast because I've got
lots of good slides for you.
I'm sorry.
First slide, please.
No show-- too bad.
We've got it.
What part of the
brain stem are we--
hindbrain, midbrain, forebrain?
STUDENT: [INAUDIBLE]
MARIAN DIAMOND: Midbrain, sure.
Here is your aqueduct.
Here are your colliculi.
Here is the cerebral peduncles.
And is a substantia nigra.
You see, it's a major
part of that midbrain.
In the next one--
at our cerebral hemispheres
thrown into folds,
what area is this?
STUDENT: Broca's.
MARIAN DIAMOND: Broca's
area-- good for you.
What area is this?
STUDENT: [INAUDIBLE]
MARIAN DIAMOND: Hearing.
What area is this?
STUDENT: Prefrontal cortex.
MARIAN DIAMOND:
Prefrontal cortex.
What area is this?
STUDENT: [INAUDIBLE]
MARIAN DIAMOND: Occipital.
This area?
[INTERPOSING VOICES]
Parietal.
Great-- next one.
And now, it shows what the
ventricles look like inside.
This is our fourth ventricle
back here in the hindbrain.
Then, we have the aqueduct.
This thin one, you
can see what happens
if a tumor gets against that.
So that's really
dangerous there,
to have such a narrow tube.
But then, we come up.
This is third ventricle.
And these are the
lateral ventricles
as they get stretched.
This would be in
the temporal lobe.
This will be back in
the occipital lobe.
And this one will be
in the frontal lobe.
So you get all, but you learn
to know those ventricles--
landmarks.
Next one.
And this shows our brain stem.
This was fourth ventricle.
Our cerebellum was over here.
We cut it off, but we wanted
to see the thalamus now.
This was all midbrain here.
Here, we come up into
the diencephalon.
The epithalamus would be on the
surface in the midline here.
We don't see the pineal
here on this slide.
But then, the
basal ganglia would
be out here with the
whole hemispheres
surrounding the whole thing.
In the next one--
and here it shows
the basal ganglia.
You have to look sharp.
Here's the head of the caudate.
Here's the putamen, pale globe,
thalamus, third ventricle.
And you could see--
this line that
divides here-- that's
that big internal
capsule with fibers
coming from the motor cortex.
Coming through there,
you break a blood vessel,
you're paralyzed on
the opposite side,
because they're all condensed
in the internal capsule because
of these masses of
nuclei that sit here.
In the next one--
and this shows the fibers as
they have to be condensed.
So this would be
internal capsule
from a different point of
view, because then, nuclei
would be in here,
coming down very narrow,
as they come down
your brainstem.
In the next one--
and this shows the
dentate gyrus forming.
The hippocampus, just to let
you see how they're related.
In the next one--
and it shows step-by-step
how it curls up,
so that you end up
with a dentate gyrus
and the hippocampus
right together,
in the hippocampal complex,
within your temporal lobe.
In the next one--
and this shows what
it really looks like.
Here's your hippocampus here.
And see the little
dentates here.
So this is where your recent
memory is processed and sent
on then to long-term memory.
And an article I just read
doesn't put long-term memory
in the frontal lobe.
I have doubts about that,
but it did not put it there.
It put in parietal,
occipital, and temporal.
In the next one--
and then, this shows
that you will eventually
learn the names of all
these gyri and what they do.
In the next one--
and I put this one in.
What is this?
[INTERPOSING VOICES]
How many have been to Rome--
a few of you.
Where is this in Rome?
[INTERPOSING VOICES]
Sistine Chapel, the roof
of the Sistine Chapel.
Here's God, and here's man.
But what's the shape of the
shroud that's around God?
[INTERPOSING VOICES]
Did Michelangelo
have fun up there,
at the top of that chapel?
Think about it.
All right, that's it.
