The Human Brain During the Third Trimester

TTectuectumm

TTe gmentumegmentum

MIDBRAIMIDBRAINN

Gl

obu

s^ p

alli

dus

(ex

ter

nal

se

gm

ent

)

Gl

obu

s^ p

alli

dus

(ex

ter

nal

se

gm

ent

)

G

lo

b

u

s^

p

a

ll

id

u

s

(i

n

te

rn

al

s

eg

m

en

t)

G

lo

b

u

s^

p

a

ll

id

u

s

(i

n

te

rn

al

s

eg

m

en

t)

Diagonal band of BrDiagonal band of Broca (voca (vertical limb)ertical limb)

Median prMedian preoptic nucleueoptic nucleuss

A

n

terior

com

m

issu

r

e

A

n

terior

com

m

issu

Ex re

te

rn

al

ca

ps

ule

Ex

te

rn

al

ca

ps

ule

Interhemispheric fissure

Lateral fissure

Raphe nucleiRaphe nuclei

Habenulo-

interpeduncular

tract

Habenulo-

interpeduncular

tract

Cl

au

str

um

Cl

au

str

um

Pu

ta

m

en

Pu

ta

m

en

V

entral

striatum

Ve

ntral

striatum

Insular gyrusInsular gyrus

POSTERIOR

COMPLEX

POSTERIOR

COMPLEX

Third

ventricle

Third

ventricle

Int

ern

alc

ap

sule

(an

ter

ior

lim

b)

Int

ern

alc

ap

sule

(an

ter

ior

lim

b)

Zona

incerta

Zona

incerta

Red

nucleus

Red

nucleus

BBA SAL GANGLIASAL GANGLIAA

S U B T H A L A M U S

S U B T H A L A M U S

THALAMUSTHALAMUS

CEREBELLUM

HYPOHYPOTHALAMUSTHALAMUS

PREOPTIC

AREA

PREOPTIC

AREA

Lateral prLateral preoptic areoptic areaea

SU

B

ST

A

N

T

IA

IN

N

O

M

IN

A

T

A

SU

B

ST

A

N

T

IA

IN

N

O

M

IN

A

T

A

Lateral Lateral hhypothalamic arypothalamic areaea

SSuubbccaallollosasal l aarreeaa

Periventricular

nucleus

Periventricular

nucleus

Inter-

peduncular

nucleus

Inter-

peduncular

nucleus

Dorsomedial

nucleus

Dorsomedial

Medial nucleus

preoptic

nucleus

Medial

preoptic

nucleus

SUPERIOR

COLLICULUS

SUPERIOR

COLLICULUS

M

ed

ia

l

g

en

ic

u

la

te

b

od

y

M

ed

ia

l

g

en

ic

u

la

te

b

od

y

Lateral

geniculate

body

Lateral

geniculate

body

S

u

b

th

a

la

m

ic

n

u

cle

u

s

S

u

b

th

a

la

m

ic

n

u

cle

u

s

Fo

rn

ix

Fo

rn

ix Central

gray

Central

gray

Oculomotor

nuclear complex (III)

Oculomotor

nuclear complex (III)

Medial longitudinal

fasciculus

Medial longitudinal

fasciculus

CeCerre bral aqueducebral aqueductt

Nucleus

accumbens

Nucleus

accumbens

Culmen

IV

,

V

Culmen

IV

,

V

C

er

e

b

r

a

l

p

ed

u

n

cl

e

C

er

e

b

r

a

l

p

ed

u

n

cl

e

LaLarge island of Callejarge island of Calleja

Meyer's loop

(visual radiation)

Meyer's loop

(visual radiation)

Germinal and transitional structures in italics

Fimbria/

fornix

Fimbria/

fornix

Dentate gyrusDentate gyrus

Para-

hippocampal

gyrus

Para-

hippocampal

gyrus

Lateral ventricle

Choroid plexus

Ammon's horAmmon's hornn

SubiculuSubiculumm

Caudate (tail)Caudate (tail)

Stria terminalisStria terminalis

DORSAL

HIPPOCAMPUS

DORSAL

HIPPOCAMPUS

In

te

r

n

a

l^

c

a

p

su

le

(p

o

st

e

ri

o

r

l

im

b

)

In

te

r

n

a

l^

c

a

p

su

le

(p

o

st

e

ri

o

r

l

im

b

)

Rostral migratory stream (source area)Rostral migratory stream (source area)

Lateral migratory stream

(infiltrates the claustrum)

Frontal neuroepithelium and

subventricular zone

Fr ontal neuroepithelium and

subventricular zone

Frontal stratified

transitional field

Fr ontal stratified

transitional field

Accumbent neuroepithelium

and subventricular zone

(infiltrated by the rostral migratory stream)

Accumbent neuroepithelium

and subventricular zone

(infiltrated by the rostral migratory stream)

Medial forebrain bundle

and ansa lenticularis

Medial forebrain bundle

and ansa lenticularis

CClaustrumlaustrum

Subgranular

zone

Subgranular

zone

Fornical

glioepithelium

Fo rnical

glioepithelium

GlioepitheliuGlioepitheliumm

AlAlvve ar glioepitheliumear glioepithelium

External germinal layer

Parahippocampal

neuroepithelium,

subventricular zone, and

stratified transitional field

Pa rahippocampal

neuroepithelium,

subventricular zone, and

stratified transitional field

Po sterior striatal neuroepithelium

and subventricular zone

Te mporal neuroepithelium and subventricular zone

Te mporal stratified transitional field

Frontal

lobe

Frontal

lobe

VERMISVERMIS

White matter

Cortical plate

Layer I

Mesencephalic glioepithelium/ependymaMesencephalic glioepithelium/ependyma

PLATE 87B