1.
Lateral
View of Lobes in Left Hemisphere
TOPOGRAPHY
Division of Cerebral Cortex into Lobes
T1
PARIETAL
TEMPORAL
PARIETAL
FRONTAL
TEMPORAL
LIMBIC
PARIETAL
2.
Medial
View of Lobes in Right Hemisphere
3.
Dorsal
View of Lobes 4.
Ventral
View of Lobes
OCCIPITAL
OCCIPITALFRONTAL FRONTALOCCIPITAL
TEMPORAL LIMBIC
FRONTAL
INSULAR: buried in lateral fissure
OCCIPITAL
Comment: The cerebral lobes are arbitrary divisions of the cerebrum, taking their names, for the most part, from overlying bones. They are not functional subdivisions of the brain, but
serve as a reference
for locating specific functions within them. The anterior (rostral) end of the frontal lobe is referred to as the
frontal pole.
Similarly, the anterior end of the temporal lobe is the
temporal pole
, and the posterior end of the occipital lobe the
occipital pole
.
TOPOGRAPHY
Lateral View of Left Hemisphere
T2
Comment:
Insula
(insular gyri) exposed by removal of overlying opercula (“lids” of frontal
and parietal cortex).
superior, middle and inferior temporal gyri
superior temporal gyrus
inferior parietal lobule:supramarginal and angular gyri
OT
OP
cerebellum
preoccipitalnotch
incision for close-upbelow
middle frontalgyrus
superior frontalgyrus
postcentralgyrusprecentral gyrus
central sulcus superior parietallobule
intraparietal sulcus
lateralsulcus
inferior frontalgyrus:
O
-orbital
T
-triangular
OP
-opercular
cut surface corresponding to incision in above figure
insula
central sulcus
SUMMARY CARTOON: GYRI
parieto-occipital sulcus
SUMMARY CARTOON: LOBES
frontal
parietal
temporal
occipital
central sulcuscentral sulcus
lateralsulcus
lateralsulcus
Lateral View of Insula
supramarginal site (posterior Wernicke’s)
caudate
Broca’s site
arcuate fasciculus
TOPOGRAPHY
T3
Language sites and arcuate fasciculus. MRI reconstruction from a volunteer
.
superior temporal site (anterior Wernicke’s)
Broca’s site
supramarginal site (posterior Wernicke’s)
Language sites
(squares) approximated from electrical stimulation sites in patients undergoing operations for epilepsy or tumor removal (Ojeman and Berger).
Broca’s site
arcuate fasciculus
transverse temporal gyrus
superior temporal gyrus
Broca’s region
Dissection of arcuate fasciculus
supramarginal site (posterior Wernicke’s)
superior temporal site (anterior Wernicke’s)
corpus callosum
arcuate fasciculus
central sulcus
central sulcus
visualradiation
TOPOGRAPHY
T4
fiber in base of pons
spinal cord
pons
central sulcus
central sulcusinternalcapsule
fiber in cerebral peduncle
fiber in pyramid
corona radiatapyramidal cell inprecentral gyrus
pyramidaldecussation
lateral fissure
medulla
middle temporal gyrus
cut surface of middlefrontal gyrus
putamen
external capsule
Lateral Dissections
supramarginal gyrus
T5
TOPOGRAPHY
Posterior View of Brain
Dorsal View of Brain
longitudinal fissure
superior frontal sulcus
precentral gyrus
middle frontal gyrus
superior frontal gyrus
parieto-occipital fissure
superior parietal lobule
postcentral sulcus
precentral sulcus
occipital lobe
longitudinal fissure
cerebellum
falx lies between the cerebral hemi-spheres in the longitu-dinal fissure
parieto-occipital sulcus
occipital lobe
tentorium lies between occipital lobes and cerebellum
medulla
LEFT HEMISPHERE RIGHT HEMISPHERE
central sulcus
postcentral gyrus
intraparietal sulcus
TOPOGRAPHY
T6
AA
B B
B
A
corpus callosum
corpus callosum
lateral fissure
lateral fissure
lateral ventricle: inferior horn
thalamus
occipital pole
thalamus
longitudinal fissure
central sulcus
FRONTAL LOBE
OCCIPITAL LOBE
caudate nucleus
caudate nucleus
lateral ventricle: posterior-horn
intraparietal sulcus
cerebellum
parieto-occipital fissure
parieto-occipital fissure
parieto-occipital fissure
lateral fissure
central sulcus
parieto-occipital fissure
T7
TOPOGRAPHY
Dorsal View of Brain
RIGHTLEFT
genu of corpus callosum
body of corpus callosum
splenium of corpus callosumoccipital lobe
thalamus
frontal lobe
transverse temporal gyrus
posterior hornof lateral ventricle
splenium of corpus callosum
internal capsule
choroid plexus
caudate nucleus
genu of corpus callosum
T8
TOPOGRAPHY
Dorsal View
thalamus
amygdala
fimbria
fornix
amygdala
inferior hornof lateral ventricle
hippocampus
caudate nucleus
thalamus
fimbria
fornix
posterior hornof lateral ventricle
internal capsule
anterior horn of lateral ventricle
caudate nucleus
internal capsule
hippocampus
inferior horn of lateral ventricle
corpuscallosum
TOPOGRAPHY
Medial View of Right Hemisphere
T9
cuneus (cuneate gyrus )corpus callosum:
lingual gyrus
fornix
cerebral aqueduct and fourth ventricle
subcallosal gyrus
parieto-occipital fissure
midbrain
pons
medulla
septum pellucidum
interventricular foramen and hypothalamus
optic chiasm
anterior commissure
genu
bodysplenium
thalamus
Medial View of Right Hemisphere: Brain Stem and Septum Pellucidum Removed
fornix
part of thalamus remaining after removal of brainstem
cingulate gyrus
isthmus of cingulate gyrus
parahippocampal gyrus
optic chiasm
anterior commissure
uncus
corpus callosum
column of fornix entering dissected hypothalamus
fimbria at edge of hippocam-pus (not seen)
subcallosal gyrus
lamina terminalis
superior andinferior colliculi
caudate
cingulate gyruscentral sulcus
calcarinefissure
cerebellarvermis
T10
TOPOGRAPHY
septum pellucidum
calcarine fissure
spinal cord
cerebral aqueduct
optic nerve
parieto-occipital fissure
fornix
pituitary fossa
superior and inferior colliculi
Magnetic Resonance Scan: midline
cingulate gyrus
midbrain
medulla
pons
third ventricle
fourth ventricle
cerebellar vermis
corpus callosum
TOPOGRAPHY
T11
1. Septum Pellucidum, Hypothalamus & Most of Thalamus Removed
2. Remaining Thalamus & Fornix Removed
head of caudate nucleus
internal capsule
thalamus cerebral peduncle
fornix body of corpus callosum
cerebral peduncle
cerebral pedunclesubstantia nigra
substantia nigra
anterior commissure
head of caudate nucleus
calcarine sulcus
cingulum
cingulate gyrus
cingulate gyrussplenium of corpus callosum
body of corpus callosum
genu of corpus callosum
calcarine sulcus
parieto-occipital fissure
cingulate gyrus
parieto-occipital fissure
pons
pons
pons
uncus
uncus
uncus
anterior commissure
anterior commissure
internal capsule
3. Caudate Removed
vermis
vermis
vermis
vermis
TOPOGRAPHY OF THE CNS
Ventral View of Brain
T12
FRONTAL LOBE
TEMPORAL LOBE
optic nerve,optic chiasm andoptic tract
floor of hypothalamus(tuber cinereum)
mammillary body
inferior temporal gyrus
olive
mammillary body of hypothalamus
cerebralpeduncle
orbital gyri
CEREBELLUM
MEDULLA
BASE OFPONS
lateral sulcus
olfactory bulb and olfactory tract
pyramid
occipital pole
temporal pole
frontal pole
Comment: The ventral surface of the brain is especially important. It is here that the blood supply to the brain enters. The brain stem and many of the cranial nerves are visible. In addition, one can see the cerebellum, portions of the frontal, temporal and occipital lobes, and the floor of the diencephalon. And it is also here that the pituitary gland (not shown) is attached to the hypothalamus by the small infundibulum (posterior to the optic chiasm).
flocculus(part of cerebellum)
parahippocampal gyrus
collateral sulcus
lateral and medialoccipitotemporal gyri
tonsil(part of cerebellum)
trigeminal nerve
T13TOPOGRAPHY
X. Vagus nerve rootlets
IV. Trochlear nerve
III. Oculomotor nerve
VI. Abducens nerve
V. Trigeminal nerve
VII. Facial nerve nerve
II. Optic nerve: The cell bodies of origin are in the retina. Half the axonscross (optic chiasm) to the oppositeoptic tract, half continuing to helpform the optic tract of the same side.
I . Olfactory bulb: olfactory nerves (in the nasal epithelium) terminatein the bulb.
Olfactory tract
mammillary body (nucleus)
Optic chiasm and optic tract
XII. Hypoglossal nerve rootlets
Cranial Nerves: Numbers and Names
cerebralpeduncle
orbital gyri
VIII. Vestibulocochlear nerve
IX. Glossopharyngeal andXI. Accessory (cranial) nerve rootlets are too small to see here: position is rostral and caudal to the vagus in the same line
olive
pyramid
ponsmiddle cerebellar peduncle
straight (rectus)gyrus
infundibulum andtuber cinereum
T14TOPOGRAPHY
Ventral View Dissections
amygdala
infundibulum
hippocampus parahippocampalgyrus
cerebral peduncle
uncus
midbrain
inferior horn of lateral ventricle
amygdala
cerebral aqueduct
hippocampus
mammillary body
splenium of corpus callosum
olfactory bulb
optic tract
posterior horn of lateral ventricle
splenium of corpus callosum
cerebral peduncle
mammillary nucleus (body)
parahippocampal gyrus
optic chiasm
olfactory tractfrontal pole
temporal pole
occipital pole
uncus
optic tract
hypothalamus
substantianigra
T15TOPOGRAPHY
Ventral Dissection: Optic Radiation
infundibulumand hypothalamus
pulvinarparahippocampalgyrus
cerebral peduncleoculomotor nerve
optic radiation: temporal (Meyer’s) loop
lateral geniculate
hypothalamus
olfactory bulband tract
optic nerve, chiasm and tract
splenium of corpus callosum
dura
medial geniculate
optic radiation
dissected lower bank of calcarine fissure
middle cerebral artery
midbrain
substantia nigra
RIGHT LEFT
TOPOGRAPHY
BRAINSTEM
1. Medial view of right hemisphere
T16
septum pellucidum
thalamus
optic chiasm
cerebellar vermis
superior &inferiorcolliculus
hypothalamus
inferior olive
midbrain
flocculus
tonsil
trigeminal nerve (V)
cerebellar hemisphere
corpus callosum
4. Lateral view from left side
medulla
pons
cerebralpeduncle
optic tract
flocculus
tonsilinferior olive
optic chiasmand tract
mammillarybody
anteriorcommissure
2. Anterior view
striatum
pyramid
hypothalamus
cerebellar hemisphere
cerebral peduncle
pyramid
cerebral aqueduct
pineal
fornix
fourth ventricle
pons
medulla
pons
medulla
internal capsule
hypothalamus
3. Posterior view: cerebellum removed
superior cerebellarpeduncle
middle cerebellarpeduncle
inferior cerebellarpeduncle
VIII
superior colliculus
inferior colliculus
cerebral peduncle
floor of 4th ventricle