The Human Brain During the Third Trimester

Choroid

plexus

Middle cerebellar peduncle

Inferior cer

ebella

r

peduncl

e

Inferior cer

ebella

r

peduncl

e

Dorsal cochlear nucleusDorsal cochlear nucleus

Inferior

cer

ebella

r

peduncle

Inferior

cer

ebella

r

peduncle

Pontocerebellar

fibers

PParaflocculuaraflocculuss

PParaflocculuaraflocculuss

Paramedian

lobule

HVIIB

Paramedian

lobu le

HVIIB

Paramedian

lobule

HVIIB

Paramedian

lobu le

HVIIB

FlocculusFlocculus

Dentate nucleuDentate nucleuss

Medial longitudinal fasciculuMedial longitudinal fasciculuss

Spinotectal tractSpinotectal tract

Dorsal longitudinal fasciculuDorsal longitudinal fasciculuss

Uvul

a

IX

Uvul

a

IX

Anterior lobe

HI-HV

Anterior lobe

HI-HV

Anterior lobe

HI-HV

Anterior lobe

HI-HV

Simplex

lobule

HVI

Simplex

lobu le

HVI

Simplex

lobule

HVI

Simplex

lobu le

HVI

IX nerve

root

V nerve root

(premyelination gliosis)

Hypoglossal nucleus (XII)Hypoglossal nucleus (XII)

Dorsal motor nucleus (XDorsal motor nucleus (X))

PrPrepositus nucleus epositus nucleus

Reticular Reticular fformatio normation

Primary fissu re

Primary fissu re

V

es

tib

ul

ar

nu

cl

ea

r

co

m

p

le

x

V

es

tib

ul

ar

nu

cl

ea

r

co

m

p

le

x

Ve

sti

bu

la

r^ n

uc

lea

r

co

m

ple

x

Ve

sti

bu

la

r^ n

uc

lea

r

co

m

ple

x

Spinocephalic tractSpinocephalic tract

Raphe nuclear compleRaphe nuclear complexx

Ve ntral cochlear nucleus

(intermingled with VIII nerve bundles)

VII nerve

Choroid

plexus

C

h

o

ro

id

p

le

x

u

s

C

h

o

ro

id

p

le

x

u

s

F

ourth

v

entricl

e

F

ourth

ventricle

Ce rCere bellar deep nucleuebellar deep nucleuss

Lateral lemniscuLateral lemniscuss

M

de

ia

ll^

em

in

sc

su

na

d

tr

ap

ze

oi

d

bo

dy

M

de

ia

ll^

em

in

sc

su

na

d

tr

ap

ze

oi

d

bo

dy

MEDULLAMEDULLA

Middle cerebellar peduncle

Middle cerMiddle cerebellar pedunclebellar pedunclee

Middle cerebellar peduncle

Superior olivary

complex

Superior olivary

complex

Motor nucleus (VII)Motor nucleus (VII)

So

lit

ar

y (^) n
uc
.
an
d
tr
ac
t
So
lit
ar
y (^) n
uc
.
an
d
tr
ac
t
C
un
ea
te
nu
cle
us
C
un
ea
te
nu
cle
us
VERMIS
HEMISPHEREHEMISPHERE
HEMISPHEREHEMISPHERE
CEREBELLUMCEREBELLUM
P O N SP O N S
External germinal layer
External germinal layer
Ansiform lobule
(Crus I HVIIA)
Ansiform lobu le
(Crus I HVIIA)
Ansiform lobule
(Crus I HVIIA)
Ansiform lobu le
(Crus I HVIIA)
Ansiform lobule
(Crus II HVIIA)
Ansiform lobule
(Crus II HVIIA)
A
n
s
i
f
o
r
m
(^) l
o
b
u
l
e
(
C
r
u
s
I
I
(^) H
V
I
I
A
)
A
n
s
i
f
o
r
m
(^) l
o
b
u
l
e
(
C
r
u
s
I
I
(^) H
V
I
I
A
)
PPontine grayontine gray
Transpontine
corticofugal tract
Germinal and transitional structures in italics
Spinal^ nucleus
and^ tract^ (V)
Spinal^ nucleus
and^ tract^ (V)
Spin
al nu
cleus
and^
tract
Spinal n (V)
ucleu
s
and^
tract
(V)
Medullary glioepithelium/ependymaMedullary glioepithelium/ependyma
PLATE 93B