ANATOMY

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ANATOMY OF THE HUMAN BRAIN
A Power-Point Tutorial on the Topography of the
Human Brain
John A. Beal, Ph. D. Professor Department of
Cellular Biology Anatomy LSUHSC-S
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CONTENTS
SLIDE

• TERMS DEFINITIONS.3-4
• MENINGES5-8
• DIVISIONS OF BRAIN..9-15
• CEREBRAL HEMISPHERES..16-31
• VENTRICLES 32-38
• THALAMUS 39-44
• BRAINSTEM45-56
• CRANIAL NERVES57-59
• CEREBELLUM 60-66
• SPINAL CORD 67-70

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• TERMS DEFINITIONS
• Colliculus rounded elevation
• Commissure a bundle of axons which cross the
  midline to connect with the same area on the
  contralateral side
• Decussation- a bundle of axons which cross the
  midline to connect with different areas on the
  contralateral side
• Fasciculus a structurally well defined bundle
  of axons
• Funiculus a large bundle of fibers made up of
  two or more fasciculi
• Fissure a deep sulcus
• Fossa - a depression
• Gyrus a folded elevation of the cerebral cortex

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• Peduncle a large bundle of axons arranged in a
  stalk or pillar-lke structure
• Stria a stripe or ridge
• Sulcus a groove or depression
• Tectum roof of ventricle in the midbrain
• Tegmentum floor of the ventricle in the
  brainstem
• Tubercle a bump
• Tract a bundle of axons in CNS with a common
  origin, termination, function
• Trigone a triangular shaped elevation

TERMS DEFINITIONS (continued)
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• MENINGES
• (Coverings of the Brain)

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MENINGES Coverings of Brain
DURA MATER
The brain and spinal cord have three connective
tissue coverings called the meninges. The outer
covering, shown here following removal of the
calvaria or skull cap, is the tough Dura Mater.
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ARACHNOID
The second layer is the Arachnoid. The Arachnoid
is a thin, glistening connective tissue layer.
The brain can be seen beneath the transparent
arachnoid. The pia mater is the third layer. The
pia mater forms a connective tissue capsule which
is intimately connected to the outer surface of
the brain and spinal cord. Cerebrospinal fluid, a
clear, colorless filtrate from the blood, is
present between the arachnoid and pia mater in
the subarachnoid space.
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DURA MATER (Reflections)
Falx Cerebri
Tentorium Cerebelli
The Dura Mater has several reflections within the
cranial vault which separate parts of the brain.
The Falx Cerebri separates the right from the
left cerebral hemisphere, the Tentorium Cerebelli
separates the Occipital Lobe of the Cerebrum from
the underlying Cerebellum, and the Diaphragma
Sellae forms a circular partition around the
stalk of the pituitary gland. The medial edge of
the Tentorium Cerebelli is called theTentorial
Incisure.
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• DIVISIONS
• OF THE
• BRAIN

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DIVISIONS OF BRAIN
FOREBRAIN - CEREBRUM (Telencephalon) -
THALAMUS) (Diencephalon)
Yellow Embryological Terms
HINDBRAIN - BRAINSTEM - Medulla
(Myelencephalon) - Pons (Metencephalon)
- Midbrain (Mesencephalon) - CEREBELLUM
(Metencephalon)
SPINAL CORD
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The divisions of the brain are seen here in a
Frontal (Coronal) Slice of the brain.
FRONTAL (Coronal) SECTION
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In this lateral view, the largest parts of the
brain, the Cerebrum the Cerebellum, can be seen.
CEREBRUM
If we take out the area of the Cerebrum outlined
in red, the brainstem and its connections to the
Cerebrum Cerebellum can be appreciated.
CEREBELLUM
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BRAIN Lateral View
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CEREBRUM
Midbrain
If we take out the area of the Cerebrum outlined
in red, the brainstem and its connections to the
Cerebrum Cerebellum can be appreciated.
CEREBELLUM
BRAINSTEM
Pons
Medulla
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BRAIN Lateral View
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BRAINSTEM Medulla-Pons-Midbrain
FOREBRAIN Thalamus-Cerebrum
The divisions of the brain and the connection of
the brain to the spinal cord is viewed here in a
midsagittal cut of the brain (Half-Brain).
Cerebrum
Thalamus
Midbrain
Cerebellum
Pons
Medulla
Spinal Cord
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BRAIN Midsagittal View
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The three divisions of the brainstem are seen
here in this anterior- inferior view.
BRAINSTEM
ANTERIOR - INFERIOR VIEW
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• CEREBRAL
• HEMISPHERES (Telencephalon)

• LABORATORY SPECIMENS UTILIZED
• Half Brain

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CEREBRAL HEMISPHERES LOBES
PARIETALLOBE
FRONTALLOBE
Transverse Fissure
OCCIPI- TALLOBE
LATERAL VIEW
INSULARLOBE
TEMPORALLOBE
-Located deep to Frontal Parietal Lobes is
not shown
The Cerebrum is divided into 5 Lobes. On the
lateral surface the Frontal Lobe is separated
from the Parietal Lobe by a fairly regular sulcus
(Central Sulcus) which passes vertically and
slightly obliquely through the central portion of
the hemisphere.
The most rostral part of the Forebrain is the
Cerebrum or Telencephalon made up of two
Cerebral Hemispheres. The Cerebrum has an outer,
highly stratified layer of gray matter called
the Cerebral Cortex which is thrown into a series
of folds or Gyri (singular gyrus) which
greatly increase the surface area of the cortex.
The grooves between the gyri are called Sulci
(singular sulcus). Deep grooves are often
referred to as Fissures. Deep to the cortex is
the white matter along with several large nuclei
located internally called Basal Ganglia.
The Occipital Lobe is separated from the Parietal
and Temporal Lobes by an imaginary vertical line
passing between the Preoccipital Notch or
indentatation and the Parieto-occipital Sulcus
which starts at the superior surface then extends
inferiorly on the medial surface.
The Temporal Lobe is separated from the Frontal
Parietal Lobes by the deep Transverse Fissure
which continues posteriorly as an imaginary line
which intersects the middle of the
occipital-parietal line.
Note the Frontal, Temporal, and Occipital Poles.
The Poles are reference points indicating the
furthest extent of the Frontal Temporal Lobes
anteriorly, and the Occipital Lobe posteriorly.
BRAIN (Left) (Lateral View)
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CEREBRAL GYRI
The major Gyri Sulci of the Cerebrum are
labelled.note The function of the Primary Motor
Primary Sensory Areas are also indicated.
The Postcentral Gyrus is the Primary
Somatosensory Cortex or Sensory Strip- the area
where sensations from the body, e.g., touch,
project into conscious awareness.
The Precentral Gyrus is the Primary Motor Cortex
or Motor Strip-the area which contains most of
the neurons which directly control voluntary
movements.
BRAIN (Left) (Lateral View)
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CEREBRAL SULCI
BRAIN (Left) (Lateral View)
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Eponyms Lateral Fissure Sylvian Fissure
Central Sulcus Rolandic Sulcus
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CEREBRAL SULCI
SUPERIOR-LATERAL VIEW
Frontal Pole
Occipital Pole
BRAIN ( Left Right Hemispheres)
(Superior-Lateral View)
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CEREBRAL GYRI
( Inferior Portion of Lateral Frontal Parietal
Lobes Resected )
LATERAL VIEW
The two Transverse Temporal Gyri Make up the
Primary Auditory Cortex where auditory
sensations (sounds) project into conscious
awareness.
BRAIN (Left) (Lateral View)
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CEREBRAL GYRI
( Parietal Lobe Resected Temporal Lobe Pulled
Inferiorly )
LATERAL VIEW
BRAIN (Left) (Lateral View)
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CEREBRAL GYRI
INFERIOR VIEW
BRAIN (Inferior View)
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CEREBRAL SULCI
BRAIN (Inferior View)
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CEREBRAL GYRI SULCI
Anterior Perforated Substance
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BRAIN (Inferior View)
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CEREBRAL GYRI
MIDSAGITTAL VIEW
The superior portion of the Lingual Gyrus the
inferior portion of the Cuneus (Lips of the
Calcarine Fissure) make up the Primary
Visual Cortex where what we see is projected
into conscious awareness.
The anterior half of the Paracentral Lobule is
the continuation of the Primary Motor Cortex or
Motor Strip of the Precentral Gyrus onto the
medial surface of the cerebrum. The posterior
half of the Paracentral Lobule is the
continuation of the Primary Somatosensory Cortex
or Sensory Strip of the postcentral gyrus onto
the medial surface of the cerebrum.
BRAIN (Left) (Mid Sagittal View)
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CEREBRAL SULCI
BRAIN (Left) (Mid Sagittal View)
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Splenium
Body
Septum Pellucidum
Fornix
MIDSAGITTAL VIEW
Rostrum
Genu
On this half-brain specimen, note the two
commissures which interconnect the right and left
hemispheres. These are the massive Corpus
Callosum, found in the roof of the anterior horn
and body of the lateral ventricle, and the
diminutive Anterior Commissure located in the
anterior-superior part of the 3rd ventricle.
The Fornix is an associational bundle of axons
which connects the Hippocampus with the
Hypothalamus. The fornix forms a portion of the
roof of the 3rd ventricle. Also note the Septum
Pellucidum, a thin membrane located in the
interval between the Corpus Callosum and the
Fornix which separates the right and left
ventricle.
The Corpus Callosum is divided into a central
part or Body, an enlarged posterior part called
the Splenium, an anterior part which forms a
C-shaped bend called the Genu and a thin inferior
part called the Rostrum.
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BRAIN (Left) (Mid Sagittal View)
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CEREBRAL GYRI
INFERIOR-MEDIAL VIEW
LEFT CEREBRUM (Inferior-medial View)
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CEREBRAL SULCI
LEFT CEREBRUM (Inferior-Medial View)
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(Septum Pellucidum Brainstem Resected)
Fornix
Body
INFERIOR-MEDIAL VIEW
Crus
Column
Fimbria
Note the C-shaped Fornix which has an anterior
portion or Column which forms the anterior and
superior boundary of the interventricular
foramen, a Body overlying the 3rd ventricle, a
Crus which interconnects with the contralateral
fornix, and a tail or Fimbria which overlies the
Hippocampus in the inferior horn of the lateral
ventricle.
LEFT CEREBRUM (Inferior-Medial View)
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• VENTRICLES

LABORATORY SPECIMENS UTILIZED - Half Brain
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LATERAL VENTRICLE (Regions)
Lateral Portion of Frontal, Parietal, Occipital,
and Superior Portion of Temporal Lobe Resected
Caudate Nucleus
LATERAL VIEW
Frontal Pole
Occipital Pole
RIGHT BRAIN DISSECTED (Lateral View)
Temporal Pole
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The anterior horn of the lateral ventricle is
located in the frontal lobe. The body of the
lateral ventricle continues posteriorly into the
parietal lobe, the posterior horn into the
occipital lobe, and the inferior horn down into
the temporal lobe
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Lateral Portion of Frontal, Parietal, Occipital,
and Superior Portion of Temporal Lobe Resected
LATERAL VENTRICLE (Structures in Inferior
Posterior Horns)
Frontal Pole
Occipital Pole
Temporal Pole
BRAIN (Right) (Lateral View)
These structures produce elevations or bumps in
the walls of the posterior and/or inferior horns
of the lateral ventricles.
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LATERAL VENTRICLE (Strucutures in Anterior Horn
Body)
Fornix Septum Pellucidum Resected Lateral
Ventricle Exposed
CAUDATE NUCLEUS (In Lateral Wall of Lateral
Ventricle)
MIDSAGITTAL VIEW
The head and body of the Caudate nucleus produce
a large elevation in the lateral wall of the
anterior horn and body of the lateral ventricle
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BRAIN (Left) (Mid Sagittal View)
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VENTRICLES
BRAIN (Left) (Mid Sagittal View)
Septum Pellucidum
3rd Ventricle
4th Ventricle
The Septum Pellucidum separates the lateral
ventricles of the two cerebral hemispheres. The
lateral ventricle connects with the Third
Ventricle via the Interventricular Foramen
(Foramen of Monroe). The dorsal thalamus and
hypothalamus make up the lateral walls of the
third ventricle. The third ventricle merges
caudally with the narrow Cerebral Aqueduct in
the midbrain which passes into the Fourth
Ventricle overlying the pons and medulla. The
roof of the fourth ventricle is the superior
medullary velum and inferior medullary velum
(not shown).
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VENTRICLES (Recesses)
Septum Pellucidum
C
3rd Ventricle
4th Ventricle
A
B
D
A Optic Recess B Infundibular Recess C
Pineal Recess D Lateral Recess
Note the Recesses (A-D) of the third and fourth
ventricles. Recesses are small extensions or
evaginations of the ventricles.
BRAIN (Left) (Mid Sagittal View)
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VENTRICLES
(Septum Pellucidum Resected)
The Fourth Ventricle opens into the Cisterna
Magna via the Median Aperture of Magendie and two
Lateral Apertures of Lushka. Identify the Choroid
Plexus in the lateral ventricle, roof of the
third ventricle, and the posterior roof and
lateral recess of the fourth ventricle.
Choroid Plexus
Lateral Ventricle
3rd Ventricle
4th Ventricle
Cerebral Aqueduct
Median Aperture
Lateral Recess to Lateral Aperture
BRAIN (Left) (Mid Sagittal View)
Interventricular Foramen
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• THALAMUS
• (Diencephalon)

• LABORATORY SPECIMENS UTILIZED
• Brainstem
• Half Brain

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• The Thalamus (Diencephalon) is part of the
  Forebrain and is divided into
• Dorsal Thalamus (Superior)
• Hypothalamus (Inferior and Medial)
• Subthalamus (Lateral to Hypothalamus)

On a half brain specimen, the Thalamus
can be identified. The Thalamus (anteroom) is
connected caudally with the midbrain and
rostrally with the cerebral hemispheres. Note
that the walls of the 3rd ventricle are
completely formed by the Thalamus. The
Hypothalamic Sulcus separates the Dorsal Thalamus
superiorly from the Hypothalamus inferiorly. The
subthalamus is located lateral to the
hypothalamus and is not visible here.
Dorsal Thalamus
MIDSAGITTAL VIEW
Hypothalamus
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BRAIN (Left) (Mid Sagittal View)
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The anterior wall of the 3rd ventricle is a thin
sheet of tissue called the Lamina Terminalis. In
the Dorsal Thalamus note the Interthalamic
Adhesion (Massa Intermedia), and the three parts
of the Epithalamus Stria Medullaris Thalami,
Habenula, and the Pineal Gland. The floor of the
Hypothalamus is made up of the Infundibulum,
which connects with the pituitary gland, and
posteriorly, the Tuber Cinereum and Mammillary
Body.
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Mammillary Body
BRAIN (Left) (Mid Sagittal View)
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BRAINSTEM
POSTERIOR VIEW
On this specimen, the following thalamic
structures can be seen 1. the Epithalamus (Stria
Medullaris Thalami, Habenula, Pineal), 2. the
Anterior Nucleus of the dorsal thalamus (Anterior
Tubercle) and, 3. the Pulvinar (the large
posterior portion of the dorsal thalamus which
overhangs the midbrain.
BRAINSTEM- THALAMUS (Posterior View)
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BRAINSTEM
Pulvinar
The Metathalamus of the Dorsal Thalamus is made
up of two nuclei tucked under the Pulvinar. These
are the Medial and Lateral Geniculate Bodies. The
Medial Geniculate Body receives input from the
Brachium of the Inferior Colliculus and is part
of the Auditory Pathway. The Lateral Geniculate
Body is part of the Visual Pathway receiving
fibers from the Optic Tract. The Lateral
Geniculate Body also gives rise to visual reflex
fibers which enter the Superior Colliculus via
the Brachium of the Superior Colliculus.
BRAINSTEM- THALAMUS (Posterior-Superior View)
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On this view of the inferior surface of the
brain, the following parts of the Dorsal
Thalamus can be observed Optic Nerve, Optic
Chiasm, Optic Tract. In the Hypothalamus, the
Infundibulum, Tuber Cinereum, Mammillary Body
can be seen.
INFERIOR VIEW
BRAIN (Inferior View)
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• BRAINSTEM
• -Medulla ( Myelencephalon)
• -Pons (Part of
  Metencephalon)
• - Midbrain (
  Mesencephalon)

• LABORATORY SPECIMENS UTILIZED
• Brainstem
• Half Brain

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Cerebrum
MIDSAGITTAL VIEW
Cerebellum
Brainstem
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BRAIN (Left) (Mid Sagittal View)
The Brainstem is connected caudally with the
spinal cord and rostrally with the Thalamus.
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• As seen in the midsagittal view, the brainstem is
  divided into 3 longitudinal tiers
• The Tectum (roof) located posterior to the
  cerebral aqueduct in the midbrain
• The Tegmentum (floor) which is located
• anterior to the ventricle throughout the
  length of the brainstem
• 3) The Pyramid in the medulla, the Basilar
  Pons in the pons, and the Cerebral Peduncle in
  the midbrain are all part of a large motor
  pathway (Pyramidal Tract) which is located
  anterior to the tegmentum

Tectum
The Tectum is further divided into a Superior
Colliculus and an Inferior Colliculus on each
side. The Posterior Commissure of the midbrain
is located just rostral to the tectum. Caudally,
the tectum is continuous with the Superior
Medullary Velum which forms the roof over the
rostral portion of the 4th ventricle.
4th Ventricle
The Medulla is separated from the Pons by the
Inferior Pontine Sulcus and the Pons is separated
from the Midbrain by the Superior Pontine
Sulcus.
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BRAIN (Left) (Mid Sagittal View)
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BRAINSTEM (Temporal Lobes Pulled Laterally)
ANTERIOR VIEW
Thalamus
Midbrain
Pons
Medulla
BRAINSTEM (Anterior View)
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BRAINSTEM
In the Medulla, the right left Pyramids are
separated by the Anterior Median Fissure. The
Pyramidal Decussation , where the Pyramidal Tract
crosses to the contralateral side, is apparent on
the surface of the caudal pyramids. The Olive is
a large bump located just lateral to the pyramids
in the rostral medulla. A tuft of Choroid Plexus
can be seen extending from the Inferior Medullary
Velum through the lateral aperture of the 4th
ventricle.
MEDULLA
BRAINSTEM (Anterior View)
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BRAINSTEM
In the Medulla, the Preolivary Sulcus is seen
between the pyramid and the olive. The
Postolivary Sulcus is located between the olive
and the Tuberculum Cinereum (not shown). The
Inferior Pontine Sulcus is located between the
medulla and pons. In the Pons, the Basilar
Sulcus or groove of the Basilar artery can be
seen.
BASILAR PONS
MEDULLA
BRAINSTEM (Anterior View)
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BRAINSTEM (Temporal Lobes Pulled Laterally)
In the Midbrain the massive right and left
Cerebral Peduncles are seen. The two peduncles
are separated by the Interpeduncular Fossa.
Posteromedial central arteries enter the brain
through the holes in the Posterior Perforated
Substance located in the floor of the fossa.
Cranial nerve III also enters the midbrain
through this fossa.
Posterior Perforated Substance
Cerebral Peduncle
Interpeduncular Fossa
BRAINSTEM (Anterior View)
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POSTERIOR VIEW
The Medulla, Pons Midbrain are delineated on
the posterior surface of the brainstem.
BRAINSTEM
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In the caudal Medulla, several structures are
seen. The Posterior Median Sulcus is on the
midline. The Posterior Intermediate sulcus
divides the Fasciculus Gacilis (long slender)
and Fasciculus Cuneatus (wedge shaped), and the
Posterolateral Sulcus separates the Fasciculus
Cuneatus from the more lateral swelling, the
Tuberculum Cinereum (Spinal Nucleus of V). The
Fasciculus Gracilis terminates rostrally in a
swelling - the Tuberculum (Nucleus) Gracilis and
the Fasciculus Cuneatus terminates in the
Tuberculum (Nucleus) Cuneatus.
BRAINSTEM
Tuberculum Cuneatus
Tuberculum Gracilis
Posterior Lateral Sulcus
Tuberculum Cinereum
Posterior Median Sulcus
Fasciculus Gracilis
Posterior Intermediate Sulcus
Fasciculus Cuneatus
CAUDALBRAINSTEM (Posterior View)
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BRAINSTEM
Lateral to the median emminence at the
junction between the medulla pons is the
Vestibular Area (Vestibular Nuclei), and lateral
to this is the Auditory Area (Dorsal Cochlear
Nucleus). The Sulcus Limitans separates the
Median Emminence from the Vestibular Area.
A swelling on either side of the
Posterior Median Sulcus called the Median
Emminence is present from the rostral medulla
through the pons. In the caudal pons a small
rounded elevation in the median emminence, the
Facial Colliculus (Motor fibers of VII passing
over the Nu of VI ) can be seen.
Rostral to the tuberculum gracilis is the floor
of the 4th ventricle or Rhomboid Fossa which
extends from the mid-medulla to the mid to
rostral Pons. The caudal most point of the
ventricle is called the Obex.

• Three V-shaped swellings can be seen in the
  caudal portion of the fossa. These are from
  medial to lateral
• Hypoglossal Trigone ( Motor Nu XII)
• Vagal Trigone (Dorsal Motor Nu X )
• Area Postrema (Emetic Center)

CAUDALBRAINSTEM (Posterior View)
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BRAINSTEM
NOTE The 4 Colliculi of the tectum are
refered to collectively as the Quadrigeminal
Plate.
The three Cerebellar Peduncles are shown here as
they enter the brainstem on each side. In the
Midbrain identify the Superior Colliculus and
Inferior Colliculus. Also identify the Brachium
of the Superior Colliculus and the Brachium of
the Inferior Colliculus which connect with the
Lateral Geniculate Body and Medial Geniculate
Body, respectively.
BRAINSTEM (Posterior View)
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BRAINSTEM
(Portions of Parietal Temporal Lobes Resected)
In this lateral view, the large Middle Cerebellar
Peduncle is seen projecting from the Basilar
Pons. In the Midbrain, the massive Cerebral
Peduncles (anterior) and the Superior Colliculus,
Inferior Colliculus, and Superior Cerebellar
Peduncle (posterior) are seen.
LATERAL VIEW
MIDBRAIN
CEREBELLUM
PONS
MEDULLA
BRAINSTEM (Lateral View)
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• CRANIAL NERVES

• LABORATORY SPECIMENS UTILIZED
• Whole Brain
• - Brainstem

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I OLFACTORY
I
CRANIALNERVES
Fila Olfactoria
ORIGIN
ANTERIOR - INFERIOR VIEW
The fila olfactoria (approximately 20 nerve
rootlets on each side) comprise the Olfactory
nerves (I) which run from the olfactory
receptors in the nasal cavity to the olfactory
bulb.
CEREBRUM (I)
To get a better view of the other cranial nerves
well ZOOM in on the area outlined in red.
Nerves are illustrated on the left side of brain
only
BRAIN (Anterior-Inferior View)
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CRANIAL NERVES (continued)
II
ORIGIN
II OPTIC (CNS Tract)
The Optic nerves (II) are large join at the
midline to form the optic chiasm, then continue
laterally as the optic tracts. The optic nerve
is not a true nerve but rather a CNS tract.
III
THALAMUS (II)
IV
III OCULOMOTOR
The Oculomotor nerves (III) emerge from a
depression in the midbrain, the interpeduncular
fossa, just caudal to the optic chiasm
MIDBRAIN (III, IV)
IV TROCHLEAR
V
V TRIGEMINAL
The Trochlear nerves (IV) are small are seen
on the lateral surface of the midbrain. They are
the only nerves which exit from the posterior
side of the brain
PONS (V, VI, VII)
VI
VI ABDUCENS
VII
VII FACIAL
The Trigeminal nerves (V) are large and emanate
from the lateral surface of the pons
VIII
VIII VESTIBULO- COCHLEAR
IX
Pontomedullary Jct. (VIII)
The Abducens nerves (VI) exit near the midline
from the inferior pontine sulcus which separates
the pons from the medulla
X
IX GLOSSOPHARYNGEAL
Moving laterally in the inferior pontine sulcus,
the Facial nerves (VII) can be seen.
XII
Slightly lateral to the facial nerve is the
Vestibulocochlear nerve (VIII)
X VAGUS
XI
MEDULLA (IX, X, XII)
XI SPINAL ACCESSORY
The postolivary sulcus is a groove running
rostrocaudally on the lateral surface of the
medulla. From this sulcus pass the small
Glossopharyngeal nerves (IX) rostrally and the
much larger Vagus nerves (X) caudally.
XII HYPOGLOSSAL
The Spinal Accessory nerves (XI) exit the
cervical cord then pass rostrally through the
foramen magnum to exit the cranial vault with
the glossopharyngeal and vagus nerves.
BRAINSTEM (Anterior View)
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The Hypoglossal nerves (XII) exit the medulla
via the preolivary sulcus
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• CEREBELLUM
• (Part of Metencephalon)

• LABORATORY SPECIMENS UTILIZED
• Whole Brain
• Half Brain
• Brainstem

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CEREBELLUM
POSTERIOR VIEW
Vermis
Posterior View
Lateral Hemispheres
The cerebellum coordinates movement and retains
motor skill (procedural) memory. The cerebellum
is divided mediolaterally into a narrow midline
portion called the Vermis which is connected
laterally to two massive (right and left)
Hemispheres. The surface (cortex) is thrown into
a series of transverse folds called Folia.
ANTERIOR VIEW
Anterior View
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CEREBELLUM
Medial Lateral Divisions
MIDSAGITTAL VIEW
The Vermis and Left Hemisphere of the cerebellum
are shown on this half brain. specimen
VERMIS
LATERALHEMISPHERE
BRAIN (Left) (Midsagittal View)
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CEREBELLUM
Anterior - Posterior Divisions ( Lobes )
POSTERIOR VIEW
ANTERIOR LOBE
POSTERIOR LOBE
Posterior View
FLOCCULONODULAR LOBE
The hemispheres together with the vermis of the
cerebellum are also divided from anterior to
posterior into 3 phylogenetic (as well as
functional) divisions or lobes. These are the
Anterior Lobe, the large Posterior Lobe, and,
the oldest part of the cerebellum the
Flocculonodular Lobe. The latter is made up of
the Nodulus of the vermis and the paired
Flocculi of the hemispheres.
ANTERIOR VIEW
Anterior View
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CEREBELLUM
Anterior - Posterior Divisions (Lobes)
The anterior posterior divisions (Lobes) are
best seen in a midsagittal cut through the
vermis. The Anterior Lobe Occupies the vermis
and hemispheres rostral to the Primary Fissure.
The Posterior Lobe makes up the bulk of the
cerebellum, comprising the remaining vermis and
hemispheres from the Primary Fissure to the
Posterolateral Fissure. The latter fissure
separates the Posterior lobe from the
Flocculonodular Lobe.
The Flocculonodular Lobe (Archicerebellum) is the
oldest part of the cerebellum and connects with
the vestibular system to coordinate balance
and equilibrium. The Anterior Lobe
(Paleocerebellum) is associated with the
development and coordination of the limbs. The
Posterior Lobe (Neocerebellum) developed in
association with the development of the
cerebral cortex and is associated with the
coordination of complex skilled movements.
LOBES
Anterior Lobe
MIDSAGITTAL VIEW
Posterior Lobe
BRAIN (Left) (Midsagittal View)
Nodulus (Of Flocculonodular Lobe)
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BRAINSTEM
The cerebellum forms the roof of the 4th
ventricle and is connected to the brainstem by 3
pairs of peduncles or pillars (shown on right
side of brainstem) . The peduncles are made up of
axons entering and leaving the cerebellum. The
Inferior Cerebellar peduncle projects
from the medulla, the large Middle Cerebellar
Peduncle projects from the Pons, and the Superior
Cerebellar Peduncle connects with the midbrain.
POSTERIOR VIEW
4th Ventricle
BRAIN STEM (Posterior View)
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BRAINSTEM
(Portions of Parietal Temporal Lobes Resected)
The connections of the Middle and Superior
Cerebellar Peduncles can be seen in this lateral
dissection. The Inferior Cerebellar Peduncle is
NOT shown. Note also the Cerebral Peduncle
(enroute from the cerebrum) on the anterior
surface of the midbrain.
LATERAL VIEW
MIDBRAIN
Cerebral Peduncle
CEREBELLUM
PONS
MEDULLA
Superior Cerebellar Peduncle
Middle Cerebellar Peduncle
BRAINSTEM (Lateral View)
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• SPINAL CORD

• LABORATORY SPECIMENS UTILIZED
• Spinal Cord

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SPINAL CORD
ANTERIOR VIEW
Spinal Cord (Anterior View)
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SPINAL CORD
Fasciculus Cuneatus
Fasciculus Gracilis
POSTERIOR VIEW
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Rostral Spinal Cord (Anterior View)
Rostral Spinal Cord (Posterior View)
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SPINAL CORD
ANTERIOR VIEW
The Conus Medullaris terminates between the L1
and L2 vertebral levels in the adult.
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Caudal Spinal Cord (Anterior View)
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• LABORATORY EXERCISE III
• BLOOD SUPPLY

LABORATORY SPECIMENS NEEDED - Whole Brain
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BRAIN BLOOD SUPPLY
Arterial Circle
Internal Carotid A.
The Brain receives its blood supply via the
Internal Carotid and the Vertebral Arteries.
ANTERIOR VIEW
BASILAR PONS
Basilar A.
Vertebral A.
CEREBELLUM
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BASE OF BRAIN
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ARTERIAL SUPPLY
ANTERIOR VIEW
The major branches of the Internal Carotid and
Vertebral-Basilar Artery Systems are shown.
BRAINSTEM (Anterior View)
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ARTERIAL SUPPLY
The arterial branches which make up the
Arterial Circle of Willis are indicated here.
BRAINSTEM (Anterior View)
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ARTERIAL SUPPLY
Three recurrent arterial branches to forebrain
structures are shown here.
BRAINSTEM (Anterior View)
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ARTERIAL SUPPLY
DORSAL THALAMUS
Central Arteries
MIDBRAIN
HYPOTHALAMUS
MIDSAGITTAL VIEW
PONS
The small Central Arteries which take origin
from the Arterial Circle. are arranged in four
groups Anteromedial from the anterior
cerebral and anterior communicating
arteries Posteromedial (also called
thalamoperforating) from the posterior
communicating and medial
portion of the posterior cerebral
arteries Posterolateral (also called
thalamogeniculate) from the lateral portion of
the posterior cerebral
arteries Anterolateral (also called
lateral striate or lenticulostriate) arising from
the middle cerebral artery
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BRAIN (Left) (Midsagittal View)
MEDULLA
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STRAIGHTSINUS
Corpus Callosum
GREAT CEREBRAL VEIN
Splenium
Thalamus
The Great Cerebral Vein is located just inferior
to the splenium of the corpus callosum. This
vessel, which drains into the Straight Sinus,
provides venous drainage for internal forebrain
structures.
BRAIN (Right) (Midsagittal View)
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THE END