The Human Brain During the Third Trimester

GW30 Horizontal

CR 260 mm

Y187-65

Level 12: Section 861

Gyrus rect

us

Gyrus rect

us

Fusiform

gyrus?

Fusiform

gyrus?

Orbital gyri

Lateral fissure

Third Third ventricleventricle

TTeemmppoorraal lol lobbee

Occipital

lobe

Occipital

lobe

Interhemispheric

fissure

Frontal

lobe

Frontal

lobe

Hypo-

thalamus

Hypo-

thalamus

TTectuectumm

MMiiddbbrraaiinn

Para-

hippocampal

gyrus

Para -

hippocampal

gyrus

Middle temporal gyrus

Inferior temporal gyrus

Lateral

occipital

gyri

Inferior

colliculus

Inferior

colliculus

Layer I

Cortical plate

White matter

11

22

33

44

55

66

77

88

99

1010

1111

1212

1313

TTe gmentumegmentum

Primary olfactory

cortex (piriform)

Endopiriform

nucleus

Endopiriform

nucleus

CeCerre bral aqueducebral aqueductt

C

er

eb

ra

lp

ed

uncl

e

C

er

eb

ra

lp

ed

uncl

e

Substantia

nigra

Substantia

nigra

Olfactory

peduncle

Olfactory

peduncle

A

m

y

g

d

a

la

A

m

y

g

d

a

la

Optic tractOptic tract

Central

nucleus

Central

nucleus

Corticomecial

complex

Corticomecial

complex

Cere bellum

(vermis)

Lateral

ventricle

H

ip

p

oc

a

mp

us

H

ip

p

oc

a

mp

us

L

at

er

al

vent

ricle

L

at

er

al

vent

ricle

Pa rahippocampal neuroepithelium, subventricular
zone, and stratified transitional field
3

5 Occipital stratified transitional field

6 Te mporal neuroepithelium and subventricular zone

1 Rostral migratory stream

4 Occipital neuroepithelium and subventricular zone

2 Fo rnical glioepithelium

7 Te mporal stratified transitional field

11 Po sterior striatal neuroepithelium and subventricular zone

12 Amygdaloid glioepithelium/ependyma

8 Alve ar glioepithelium

10 Lateral migratory stream (cortical)

9 Subgranular zone (dentate)

14 Subpial granular layer (cortical)

13 External germinal layer (cerebellum)

Remnants of the germinal matrix, migratory streams, and transitional fields

14

See detail of brain core and

cerebellum in Plates 141A and B.

Damaged areas in section

PLATE 123