The Human Brain During the Third Trimester

C

o

r

t

ic

a

l

p

la

te

An

te

rio

r lo

be

(H

I-H

V)

An

te

rio

r lo

be

(H

I-H

V)

Simplex

lobule

(HVI)

Simplex

lobu le

(HVI)

Primary fissure

Ansiform lobule

crus II

(HVIIA)

Ansifo rm lobu le

crus II

(HVIIA)

Ansiform lobule

crus I

(HVIIA)

Ansiform lobu le

crus I

(HVIIA)

Olfactory

tubercle

Olfactory

tubercle

Orbital gyrusOrbital gyrus

Lateral ventricle

A

M

Y

G

D

A

L

A

A

M

Y

G

D

A

L

A

Choroid

plexus

Choroid

plexus

Corpus

callosum

(splenium)

Corpus

callosum

(splenium)

BASAL

GANGLIA

BA SAL

GANGLIA

VENTRAL

HIPPOCAMPUS

VENTRAL

HIPPOCAMPUS

PPONSONS

Nerve (^) V
(root)
Nerve (^) V
(root)
PulvinarPulvinar
P
O
S
T
E
R
IO
R
C
O
M
P
L
E
X
P
O
S
T
E
R
IO
R
C
O
M
P
L
E
X
Floccular pedunclFloccular pedunclee
Fourth ventricle
(lateral recess)
Fourth ventricle
(lateral recess)
Dorsal
cochlear
nucleus
Dorsal
cochlear
nucleus
Superior
vestibular
nucleus
Superior
vestibu lar
nucleus
Optic
tract
Optic
tract
Nucleus
accumbens
Nucleus
accumbens
En
tor
hin
al
co
rte
x
En
tor
hin
al
co
rte
x
SubiculuSubiculumm
Anterior
commissure
Anterior
commissure
Choroid plexus
Induseum griseum?Induseum griseum?

DORSAL

HIPPO-

CAMPUS Cin

gu

la

te^

gy

ru

s

(r

et

ro

sp

le

ni

al^

ar

ea

)

Ci

ng

ul

at

e^ g

yr

us

(r

et

ro

sp

le

ni

al^

ar

ea

)

C

o

r

p

u

s^

c

a

llo

su

m

C

o

r

p

u

s^

c

a

llo

su

m

11

11

33

22

44

44

55

12

99

12

13

CEREBELLUM

(HEMISPHERE)

Ci

ng

ulu

m

Ci

ng

ulu

m

Substantia

nigra

Substantia

nigra

DO

RS

AL

CO

MP

LE

X

DO

RS

AL

CO

MP

LE

X

CENTRAL

COMPLEX

CENTRAL

COMPLEX

Centromedian

nucleus

Centromedian

nucleus

DorsolateralDorsolateralnucleusnucleus

Sub-

thalamic

nucleus

Sub-

thalamic

nucleus

In

fe

ri

o

r

ce

re

b

el

la

r

p

ed

u

n

c

le

In

fe

ri

o

r

ce

re

b

el

la

r

p

ed

u

n

c

le

Middle

cerebellar peduncle

Middle

cerebellar peduncle

Ventral

postero-

lateral

nucleus

Ve ntral

postero-

lateral

nucleus

Ventral

postero-

medial

nucleus

Ve ntral

postero-

medial

nucleus

Ventral

lateral

nucleus

Ve ntral

lateral

nucleus

Ventral

Anterior

nucleus

Ve ntral

Anterior

nucleus

THALAMUSTHALAMUS

SU

BT

HA

LA

MU

S

SU

BT

HA

LA

MU

S

Dentate nucleuDentate nucleuss

Para-

flocculus

(HIX)

Para -

flocculus

(HIX)

Biventral

lobule

(HVIII)

Biventra l

lobu le

(HVIII)

Paramedian

lobule

(HVIIB)

Paramedian

lobu le

(HVIIB)

C

en

tr

al

la

te

ra

l

nu

cl

eu

s

C

en

tr

al

la

te

ra

l

nu

cl

eu

s

P

ar

a

ce

nt

ra

ln

uc

le

us

P

ar

a

ce

nt

ra

ln

uc

le

us

Medial

geniculate

body

Medial

geniculate

body

R

E

T

IC

U

L

A

R

B

E

L

T

(R

etic

ula

rn

uc

le

us

)

R

E

T

IC

U

L

A

R

B

E

L

T

(R

etic

ula

rn

uc

le

us

)

C

ere

bra

lpeduncle

C

ere

bra

lpeduncle

I

n

te

r

na

l

c

a

p

s

u

l

e

I

n

te

r

na

l

c

a

p

s

u

l

e

In

te

rn

a

lc

a

ps

u

le

(a

n

te

ri

or

lim

b)

In

te

rn

a

lc

a

ps

u

le

(a

n

te

ri

or

lim

b)

Caudate

(head)

Caudate

(head)

V

E

N

T

R

A

L

CO

MPLE

X

V

E

N

T

R

A

L

CO

MPLE

X

C

or

tic

om

ed

ial

co

m

plex

C

or

tic

om

ed

ial

co

m

plex

B

as

o

la

te

ra

lc

om

pl

ex

B

as

o

la

te

ra

lc

om

pl

ex

S

p

in

o

ce

r

eb

el

la

r

tr

a

ct

?s

S

p

in

o

ce

r

eb

el

la

r

tr

a

ct

?s

In

fe

ri

or

ce

re

be

lla

rp

ed

unc

le

In

fe

ri

or

ce

re

be

lla

rp

ed

unc

le

Fornix

Primary olfactory cortexPrimary olfactory cortex

Lateral olfactory tractLateral olfactory tract

Pa

rie

to-

occ

ipi

tal

su

lcu

s

Pa

rie

to-

occ

ipi

tal

su

lcu

s

Calcarine sulcuCalcarine sulcuss

Pa

ra

hi

pp

oc

am

pa

l^ g

yr

us

Pa

ra

hi

pp

oc

am

pa

l^ g

yr

us

Occipital lobeOccipital lobe

C

o

r

t

ic

a

l

p

la

te

White matterWhite matter

Brachium of the inferior colliculusBrachium of the inferior colliculus

Zona

incerta

Zona

incerta

Globus pallidus

(internal

segment)

Glob us pallidus

(internal

segment)

Globus pallidus

(external

segment)

Glob us pallidus

(external

segment)

SUBSTANTIA

INNOMINATA

SUBSTANTIA

INNOMINAT A

Diagonal band of Broca

(horizontal limb)

Diagonal band of Broca

(horizontal limb)

Medullary laminaMedullary lamina

Str

ia

te

rm

in

al

is

Str

ia

te

rm

in

al

is

Damaged arDamaged areaea

44

7 Alve ar glioepithelium

8 Amygdaloid glioepithelium/ependyma

10 Anteromedial striatal neuroepithelium and subventricular zone

9 Anterolateral striatal neuroepithelium and subventricular zone

6

Pa rahippocampal neuroepithelium, subventricular

zone, and stratified transitional field

2 Fr ontal neuroepithelium and subventricular zone

12 External germinal layer

11 Strionuclear glioepithelium

1 Rostral migratory stream (source area)

4 Callosal glioepithelium

5 Fo rnical glioepithelium

13 Subpial granular layer

3 Fr ontal stratified transitional field

66

88 77

13

1010

1010

1111

Stem cells of the

choroid plexus?

Ventral

cochlear

nucleus?

Ventra l

cochlear

nucleus?

Remnants of the germinal matrix,

migratory streams, and transitional fields

LayLayer er II

Stem cells of the choroid plexus?

PLATE 204B