The Human Brain During the Third Trimester

F

ourth

v

entricl

e

F

ourth

ventricl

e

La

te

ra

l le

m

nis

cu

s

La

te

ra

l le

m

nis

cu

s

Lateral lemniscu

s

Lateral lemniscu

s

Nerve V (root)

Nerve V

Nerve V (boundary cap)

Moto r

nucleus (VII)

Moto r

nucleus (VII)

Moto r

nucleus (VII)

Moto r

nucleus (VII)

Abducens nucleus (VI)Abducens nucleus (VI)

Superior

olive

omplex

Superior

olive

omplex

Medial longitudinal

fasciculus and

tectospinal tract

Medial longitudinal

fasciculus and

tectospinal tract

Dorsal longi-

tudinal fasciculus

Dorsal longi-

tudinal fasciculus

Transpontine corticofugal tract Reticular Reticular ffo rmationormation

Pontocerebellar fibers

DEEP NUCLEIDEEP NUCLEI

Pyramis

(VIII)

Pyramis

(VIII)

Tuber

(VIIa)

Tuber

(VIIa)

Nodulus

(X)

Nodulus

(X)

Uvula

(IX)

Uvula

(IX)

Simplex lobu le (HVI)

Anterior lobe (HIV-HV)

Raphe nuclear compleRaphe nuclear complexx

Spinal nucleus

and tract (V

)

Spinal nucleus

and tract (V

)

Spinal nucleus

and tract (V)

Spinal nucleus

and tract (V)

Primary fissure

Dentate nucleuDentate nucleuss

Crus I,

ansiform lobule

(HVIIA)

Crus I,

ansiform lobu le

(HVIIA)

Crus II,

ansiform lobule

(HVIIA)

Crus II,

ansiform lobu le

(HVIIA)

Crus II,

ansiform lobule

(HVIIA)

Crus II,

ansiform lobu le

(HVIIA)

Pa

ram

edia

n lo

bu

le (H

VIIB

) a

nd^

biv

entr

al lo

bule

(H

VIII)

Pa

ram

edia

n lo

bu

le (H

VIIB

) a

nd^

biv

entr

al lo

bule

(H

VIII)

R

et

ic

u

la

r

et

gm

en

ta

l

nu

cl

eu

s

R

et

ic

u

la

r

et

gm

en

ta

l

nu

cl

eu

s

Infe

cer rior

ebell

pedunar

cle

Infe

cer rior

ebell

pedunar

cle

Vestibular

nuclear

complex

Vestibular

nuclear

complex

Vestibular

nuclear

complex

Vestibular

nuclear

complex

Choroid

plexus

Choroid

plexus

Inferior

cer

ebella

r

peduncl

Inferiore

cer

ebella

r

peduncl

e

Dor

sal

coc

hlea

r^ nu

cleu

s

Dor

sal

coc

hlea

r^ nu

cleu

s

Fourth ventricle

(lateral recess)

Fourth ventricle

(lateral recess)

Floccular

peduncle

Floccular

peduncle

FlocculuFlocculuss

M

id

dl

e

ce

re

b

el

la

r

pe

du

n

cl

e

M

id

dl

e

ce

re

b

el

la

r

pe

du

n

cl

e

Dor

salcochl

ea

r

nu

cl

eu

s

Dor

salcochl

ea

r

nu

cl

eu

s

M

ed

ia

l

le

m

ni

sc

us

M

ed

ia

l

le

m

ni

sc

us

T

ra

p

ez

oi

d

(^) b
do
y
T
ra
p
ez
oi
d
(^) b
do
y
Mid
dle
and
Inf
erio
r
cere
bella
r^ pe
dun
cles
Mid
dle
and
Inf
erio
r
cere
bella
r^ pe
dun
cles
Middle and Inferior
cerebellar peduncles
Middle and Inferior
cerebellar peduncles
M
i
d
d
le
c
er
ebel
la
r
p
e
d
u
n
c
le
M
i
d
d
le
c
er
ebel
la
r
p
e
d
u
n
c
le
Cr
us
I,
an
sif
or
m
lo
b
u
le
(H
V
II
A
)
Cr
us
I,
an
sif
or
m
lo
b
u
le
(H
V
II
A
)
Pa
ra
m
ed
ian
lo
bu
le (H
V
IIB
)
an
d
biv
en
tr
al lo
bu
le (H
V
III
)
Pa
ra
m
ed
ian
lo
bu
le (H
V
IIB
) a
nd
biv
en
tr
al lo
bu
le (H
V
III
)
Germinal and transitional structuGerminal and transitional structurres ines in italicsitalics
CEREBELLUM
VVermisermis
HemispheHemispherree
Pontine gray
P O N SP O N S
External germinal layer
External germinal layer
PPontine glioepithelium/ependymaontine glioepithelium/ependyma
Germinal
trigone
Germinal
trigone
PLATE 147B