2022 Edition
Sheep Brain Atlas
A Photographic Guide
Neuroanatomy Laboratory
Dr. Janelle LeBoutillier
Acknowledgements
When this Sheep Brain Atlas was originally conceived in 2007, the idea was to
compile a selection of brain dissections which could be used by students to study
outside of the lab using a web-based platform. The goal was to provide students
with images that reflected our course content and a self-test tool to assess their
learning. All students enrolled in NROB60 at UTSC have access to this atlas via our
course page. Feedback from students, primarily through course evaluations over
the past years, resulted in the production of a printed version of the atlas,
dissection guides and more detailed study worksheets to further assist them in
successfully completing the laboratory content. Together, the aim of the printed
version of the sheep brain atlas and the web supplement is to provide students
in our introductory anatomy course with the tools to prepare for and succeed in
our labs!
This book would never have become reality without the help and suggestions of
many supportive colleagues and students. In particular, I would like to
acknowledge the contributions of Dr. Zenya Brown, Sadia Riaz, Michael
Murphy-Boyer, Ken Jones, and Yomi Gammada. Dr. Zenya Brown and Sadia Riaz,
experienced teaching assistants with the course for many years who share my
enthusiasm for brain anatomy, played a pivotal role designing and revising the
2014-2022 Editions of the Sheep Brain Atlas. Michael Murphy-Boyer, an instructional
multimedia designer working on this project in the Information and Instructional
Services at UTSC created our webversion of the sheep brain atlas. Ken Jones, the
principal photographer at UTSC provided the original custom photographic and
imaging services, and Yomi Gammada, who as a UTSC undergraduate was
involved with the majority of data input with the original Atlas 2007 edition.
Many others have assisted with various aspects of this project for the 2007, 2010
2014 and 2016 editions. I wish to thank (in alphabetical order): Zac Campbell,
Daryl Cheung, Victoria Fugariu, Kimia Honarmand, Jaspreet Johal , Matthew
John, Sarah Johnson, Crystal Mahadeo, Paul McKeever, Andreea Moraru,
Vito Oriente, Christina Plaginannakos, Vishwajeet Tummala, Tina Wang and
Ruth Warre for their contributions.
Lastly, I would like to express my appreciation to University of Toronto
Scarborough for their financial support through teaching enhancement grants
without which this project could not have succeeded.
Please send all correspondence to:
Dr. Janelle C. LeBoutillier
Department of Psychology
University of Toronto Scarborough
1265 Military Trail, Scarborough ON M1C 1A4
janelle.leboutillier@utoronto.ca
Sheep Brain Atlas: A Photographic Guide
Copyright by Janelle C. LeBoutillier, 2022
Previous Editions: 2007, 2010, 2014, 2015, 2016
1
Contents
Introduction
Anatomical terminology
Anatomical characteristics of the brain
Planes of orientation
List of Acronyms
Major Subdivisions of the Brain
Major Neuronal Circuits
Naming Structures on Bellringer Tests
Study Sheets
Sheep Brain Dissections
Photoseries 1
Photoseries 2
Photoseries 3
Photoseries 4
Photoseries 5
Photoseries 6A
Photoseries 6B
Appendix
3
4
5
5
6
7
8
9
10
24
34
41
53
70
79
92
99
2
Introduction
Welcome to the laboratory component of Neuroanatomy Laboratory
(NROB60). The purpose of this lab is to provide you with hands-on anatomy
training, familiarizing you with the three dimensional structure of the
mammalian brain. A good understanding of (i) the location and
connections between brain regions (learned here in the lab), and (ii) the
physiology of neuronal activity (learned in lecture), together form the
fundamental basis of your neuroscience training.
Labs will examine large-scale neuroanatomical structures (gross anatomy)
through a series of dissections. To accomplish this task, The Sheep Brain
Atlas: A Photographic Guide is divided into six Photoseries, each designed to
visually guide you through the dissections conducted on your assigned
sheep brain over the term. In brief summary:
Photoseries 1 – examines the external features of the dorsal, lateral and
ventral surfaces of the sheep brain
Photoseries 2 – reviews the 12 cranial nerves, their point(s) of attachment,
and the type of sensory and/or motor information each nerve carries
Photoseries 3 – the sheep brain is bisected along the longitudinal midline
(midsagittal plane), showing the medial face of the two hemispheres
Photoseries 4 – details a hippocampal dissection, which reveals components
of the diencephalon
Photoseries 5 – a transverse (horizontal) cut is made at two depths revealing
the dorsal and ventral components of the diencephalon, basal ganglia and
limbic system
Photoseries 6 – the sheep brain is sectioned coronally through the cerebrum
(6A) and cerebellum (6B), to reveal cortical and subcortical structures,
including several fiber tracts and nuclei not visible in other planes.
Before we begin, I’d like to offer a word of advice: learning neuroanatomy
requires time and effort, as it is the equivalent of learning both a new
language and “map of the brain” simultaneously. So allow yourself lots of
time to practice the nomenclature using the various study aids we have
designed to facilitate your learning. These include:
•
•
•
•
The Study Sheets in this Atlas (pg 11-23)
The “Random label” and “Full label” self-test feature of the online Atlas
Dissection videos
Weekly office hours
Teaching this course is one of my passions. I hope you enjoy the material
covered and I wish you success with your studies!
Dr. Janelle LeBoutillier
3
Anatomical Terminology
In anatomy, using standard directional
terms and planes of orientation enables
us to describe the locations of structures
in relation to other structures/locations.
Below is a list of terms that will be
frequently used in the labs.
Dorsal
(Superior)
Posterior
(Caudal)
Anterior/Rostral: near the head end or
toward the front plane
Posterior/Caudal: located behind a part
or toward the rear
Ventral
(Inferior)
Dorsal
(Superior)
Dorsal: relating to the back or top side of
an animal
Ventral: relating to the front or bottom
side of an animal
Superior: above or on the upper surface
Inferior: below or on the lower surface
Posterior
(Caudal)
Medial: referring to the middle of the
body or structure (towards the midline)
Lateral: situated at or extending to the
side (away from the midline)
Proximal: a part of the body that is closer
to the center of the body than another
part
Distal: a part of the body that is located
far from a point of reference
Anterior
(Rostral)
Ventral
(inferior)
Proximal
(closer to
midline)
Ipsilateral: on the same side of the body
Contralateral: on the opposite side of the
body
Efferent: away from; e.g. efferent motor
neuron- carries information away from
CNS
Afferent: towards; e.g. afferent sensory
neuron- carries information towards CNS
Anterior
(Rostral)
Distal
(Further from midline)
Lateral!
Medial!
4
Anatomical Characteristics of the Brain
Lissencephalic (Greek: lissos = smooth;
enkephalos = brain): a brain in which the
cerebral hemispheres are devoid of
convolutions (gyri) and clefts (sulci)
Gyrus
(“hill”)
Sulcus
(“valley”)
Fissure
Gyrencephalic (Greek: gyros = spiral;
enkephalos = brain): a brain in which the
cerebral hemispheres are highly folded
and convoluted due to presence of gyri
and sulci
Gyrus (pl. gyri): the ”hill" or convolution on
the surface of the brain; caused by the
folding of the cortex
matter"
White
matter"
Sulcus (pl. sulci): the “valley” or cleft on
the surface of the brain, separating the
gyri
Fissure: is a deep sulcus; elongated cleft,
natural division
Grey matter: consists of neuronal cell
bodies (soma) and dendrites
White matter: is composed of bundles of
myelinated axons; it appears white to the
naked eye because myelin is primarily
composed of lipid (fat)
Planes of Orientation
Sagittal Cut (conducted in PS3)"
Right"
Left"
Horizontal Cut (conducted in PS5)"
Dorsal"
Sagittal plane: vertical plane that divides
the brain into right and left parts
Ventral"
Horizontal (Transverse) plane: divides the
brain into dorsal and ventral (superior/
inferior) parts; is perpendicular to coronal
and sagittal planes
Coronal Cut (conducted in PS6)"
Coronal (frontal) plane: vertical plane that
divides the brain into anterior and posterior
(rostral/caudal) sections
Posterior"
Anterior"
5
List of Acronyms
NOTE: On bellringer tests you are required to provide the complete full name of all
anatomical structures. The acronyms below have been utilized in this course as a
space saving technique on study sheets and slides shown during labs.
III
IV
A
AL
Alv
ATN
B
C
CA
CC
CN
CP
DG
F
Fl
G
GP
H
Hb
HI
Hy
IC
LGB
LV
Third ventricle
Fourth ventricle
Amygdala
Ansiform lobule
Alveus
Anterior thalamic
nuclei
Body of corpus
callosum
Claustrum
Cerebral aqueduct
Corpus callosum
Caudate nucleus
Cerebral peduncle
Dentate gyrus
Fornix
Flocculus
Genu of corpus
callosum
Globus pallidus
Hippocampus
Habenula
Habenulointerpeduncular
tract
Hypothalamus
Inferior colliculus
Lateral geniculate
body
Lateral ventricle
MB
Med
MGB
MI
Mid
MTN
OC
OT
OB
OTb
OTr
P
PB
Pf
PmL
Pv
S
SC
SF
SM
SN
SP
SpC
T
TB
VTN
Mammillary body
Medulla
Medial geniculate
body
Massa intermedia
Midbrain
Medial thalamic
nuclei
Optic chiasm
Optic tract
Olfactory bulb
Olfactory tubercle
Olfactory tract
Putamen
Pineal body
Paraflocculus
Paramedian lobule
Pulvinar
Splenium of corpus
callosum
Superior colliculus
Subcallosal fasciculus
Stria medullaris
Septal nucleus
Septum pellucidum
Spinal cord
Thalamus
Trapezoid body
Ventral thalamic nuclei
6
Major Subdivisions of the Sheep Brain
The brain is divided into numerous subdivisions based on embryonic and
evolutionary development. These include the:
1. FOREBRAIN
Telencephalon – the cerebrum:
Cerebral cortex:
- Frontal lobe
- Parietal lobe
- Occipital lobe
- Temporal lobe
Subcortical structures:
- Hippocampus
- Amygdala
- Basal ganglia
Rhinencephalon:
- Olfactory tract
- Pyriform lobe
Diencephalon – the “interbrain”;
connects midbrain to cerebrum:
- Thalamus
- Hypothalamus
- Mammillary body
- Pineal body
2. MIDBRAIN
Mesencephalon – the midbrain:
- Cerebral peduncles
- Superior colliculus
- Inferior colliculus
3. HINDBRAIN
Metencephalon
- Cerebellum
- Pons
Myelencephalon
- Medulla
VENTRAL SURFACE (PS2)
CP
SpC
Med TB Pons
OT
MB OC
OTr
OB
Brain Stem
The brain stem =
mesencephalon,
pons + medulla
MIDSAGITTAL CUT (PS3)
SC PB
IC
T
Cerebellum
SpC
Cingu
Mid
Med
Pons
MB
late gy
Hy
rus
OC
7
Brain Stem
Major Neuronal Circuits
Although structurally discrete, many regions of the brain are functionally
interconnected due to dense neuronal projections between them. Such
neuronal networks form “systems” that govern complex behaviours. Two
major systems found in the sheep brain are the basal ganglia and limbic
system.
THE BASAL GANGLIA
The basal ganglia is a subcortical
system composed of several
structures, including the:
CUT E
CN
• Striatum: caudate nucleus,
putamen
• Pallidum: globus pallidus,
ventral pallidum
• Substantia nigra
• Thalamus
This system is primarily associated
with voluntary motor movements,
action selection and procedural
learning.
P
GP
CUT H
Damage to the basal ganglia can
lead to movement disorders such
as Parkinson’s and Huntington’s
disease.
T
SN
THE LIMBIC SYSTEM
The limbic system is a complex
network of numerous structures,
including the:
•
•
•
•
•
Hippocampus
Amygdala
Anterior thalamic nuclei
Fornix
Prefrontal cortex
This system mediates a variety of
complex behaviours including
emotion, memory and motivation.
CUT F
H
ATN
A
F
Prefrontal
Cortex
8
Naming Structures on Bellringer Tests
As you proceed through each Photoseries you will encounter several structures that are
comprised of numerous anatomically discrete regions/lobules/nuclei. These include the:
• Cerebellum (PS3)
• Corpus callosum (PS4)
• Thalamus (PS3-6)
• Hippocampal formation (PS3-6)
• Ventricular system (PS3-6)
On bellringer tests you are expect to provide the
most specific name for the structure. For example,
in the image on the right, the appropriate answer
for the green pin is “simplex” not “cerebellum”.
The Thalamus
• In PS3, you are viewing the midsagittal surface
of the left and right thalamus. In this dissection,
you can only see the gross anatomical
boundaries of the structure, plus the area where
it crosses the midline (massa intermedia). This is
because the majority of the thalamic nuclei are
located lateral to the midline.
Thus, it is accurate in PS3 dissections to
state “thalamus” or “massa intermedia”
as your answer, depending on which
structure is pinned
• In PS4, PS5 and PS6, the individual thalamic
nuclei are visible, therefore you must state which
specific nuclei has been pinned as your answer
You are responsible for knowing which
nuclei are visible in each cut/dissection
based on the labeling in your atlas
The Hippocampal Formation
• In PS3, the specific components of the
hippocampal formation can not be seen.
Again, this is because most of the components
are located lateral to the midline.
Thus, it is accurate in PS3 dissections to
state “hippocampal formation” as your
answer
• In PS4, PS5 and PS6, the individual components
of the hippocampal formation are visible,
therefore you must state which specific structure
has been pinned as your answer
You are responsible for knowing which
areas of the hippocampal formation are
visible in each cut/dissection based on
the labeling in your atlas
Cerebellum
HF
CC
MI
VENTRAL
SURFACE
DORSAL
SURFACE
9
Study Sheets
Note: The following study sheets do not label all
neuroanatomical structures identified in Photoseries 1-6.
Students are responsible for learning all structures as
presented in each Photoseries.
See Appendix for answers.
Neuroanatomy Laboratory
Dr. Janelle LeBoutillier
Cerebrum (latin) = brain
Cerebellum (latin) = little
brain
PHOTOSERIES 1: Dorsal and Lateral Structures
FIG. 1
5
4a
3
4b
6
2
1.
_______________________
2.
_______________________
3.
_______________________
4a. _______________________
1
b. _______________________
Cerebellum
5.
_______________________
6.
_______________________
Prefix definitions:
Endo– inside; within
Ecto– outer; external
Supra– above; over
Anterior
What is the difference between a sulcus and gyrus?
FIG. 2
5
4
7
3
6
1
2
Cerebellum
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
Anterior
The olfactory tract and
pyriform lobe are
continuous structures
What is the difference between a sulcus and fissure?
FIG. 3
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
Anterior 8.
_______________________
1
Cerebellum
2
3
4
5
6
8
7
The olfactory bulbs
are located outside
of the brain
PHOTOSERIES 2: Ventral Surface Structures
FIG. 1
Once axonal
projections from the
olfactory bulb enter
the brain, the
structure becomes
the olfactory tract
1
2
5
4
3
Tracts are bundles
of myelinated
axons that connect
one part of the
brain to another
6
(center
‘hole’)
7
Posterior
Which structures comprise the brain stem?
1.
___________________
2.
___________________
3.
___________________
4.
___________________
5.
___________________
6.
___________________
7.
___________________
FIG. 2
Pons (latin) = bridge
The trapezoid body,
olive and pyramidal
tract are regions of
the medulla
The ventral median
fissure runs along
the ventral surface
of the medulla and
spinal cord
1
Medulla
Spinal
Cord
5
2
1.
___________________
3
2.
___________________
3.
___________________
4.
___________________
5.
___________________
6.
___________________
4
6
PHOTOSERIES 2: Cranial Nerves and Tracts
NAMING: Oh once one takes the anatomy final very good vacations seem heavenly
FUNCTION: Some say marry money but my brother says bigger brains matter more
FIG. 1
Note the point of attachment of
each cranial nerve
1
POINTS OF CRANIAL
NERVE ATTACHMENT:
Midbrain
2
Pons
Medulla
3
4
5
6
8
7
9
(on lateral
surface of
midbrain)
12
1.
__________________________
2.
__________________________
3.
__________________________
4.
__________________________
5.
__________________________
6.
__________________________
7.
__________________________
8.
__________________________
9.
__________________________
10. __________________________
10
11. __________________________
11
12. __________________________
13. __________________________
13
14. __________________________
15. __________________________
What is the difference between a
nerve and a tract?
PHOTOSERIES 3: The Rostral Cerebellum
FIG. 2
Primary
Fissure
4
5
6
7
3
2
1
Pons
Rostral
The lingula, centralis and culmen
together comprise the anterior
lobe of the cerebellum
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
PHOTOSERIES 3: The Cerebellum
FIG. 1
Primary
Fissure
5
4
6
AL
PmL
Pf
3
2
7
1
Fl
Spinal
Cord
Pons
Medulla
Lateral
5
4
6
3
SC
2
IC
7
8
1
Pons
Medulla
Midsagittal
FIG. 3
3
5
4
2
1
Caudal
Spinal Cord
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
Compare Figure 1 & 2: Note that
the nodulus can only be seen in
a midsagittal cut because it is
located at the base of the
cerebellum
FIG. 2
Primary
Fissure
Prefix definition:
Para– beside; alongside of
Flocculus – tuft of wool
Vermis – worm
Spinal
Cord
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
8.
_______________________
Note that the ansiform lobule
and flocculus cannot be seen in
the caudal (posterior) view
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
The fornix is a
component of the
hippocampal
formation
10. _______________________
_______________________
9.
_______________________
7.
_______________________
8.
_______________________
6.
_______________________
7.
_______________________
5.
_______________________
_______________________
4.
6.
_______________________
3.
_______________________
_______________________
2.
The corpus callosum
is a commissure – a
bundle of myelinated
axons that cross the
midline
5.
_______________________
1.
_______________________
9
4.
8
7
6
_______________________
5
3.
Pons
3
_______________________
Med
Mid
1
2
2.
5
6 7
What is the difference between a commissure and a tract?
4
3
_______________________
2
1.
Pons
Mid
1
FIG. 2
What is the function of the corpus callosum? Why is it white?
Med
FIG. 1
PHOTOSERIES 3: Midsagittal Structures
10
The massa
intermedia is the
region of the
thalamus that
connects the left
thalamus & right
thalamus at the
midline
Prefix definition:
Hypo– under;
beneath
Anterior
PHOTOSERIES 3: The Midsagittal Ventricular System
FIG. 1
Choroid
Plexus
2
1
3
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
4
PHOTOSERIES 4: Major Arteries and Brain Stem Nuclei
FIG. 2
2
3
1
The Circle of Willis is
composed of arteries labeled
1,3 and 4, plus the anterior
communicating artery and
internal carotid arteries.
(Arteries 2 & 5 supply the
brain but are not considered
part of the Circle of Willis).
4
5
Anterior
Communicating
Artery
(under optic chiasm)
Ventral
FIG. 3
“Name the
space”
IC
Spinal
Cord
Dorsal
1
2 5
3 4
SC
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
16
PHOTOSERIES 4: Hippocampal Formation and Diencephalon
The fimbria (white matter) is
the most anterior aspect of
the hippocampal formation;
it is smooth and white in
appearance
FIG. 1
SC
2
5
1
4
6
3
‘membrane
separating LV’
Dorsal view of the
Hippocampal formation
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
The dentate gyrus (grey
matter) and hippocampal
fissure (groove) are only
visible in the ventral view
FIG. 2
5
3
2
4
6
8
9
1
Ventral view of the
Hippocampal formation
FIG. 3
1
SC
Pons
Lateral
2
3
5
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
8.
_______________________
9.
_______________________
The optic chiasm, optic tract,
LGB and pulvinar are one
continuous structure
Optic
Radiation
IC
7
1.
4
Internal
Capsule
6
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
1
LV
2
3
5
4
LV
6
7
Cut A2
FIG. 2
LV
III
4
5
3
2
6
1
(the “space”)
CA
7
IV
Cut B2
7.
_______________________
Observe which structures can be seen in the A and/or B cut, as well as the overall shape of the brain, to determine which
transverse cut you’re examining.
1. _______________________
Globus Pallidus –
The pulvinar, LGB and MGB
1. _______________________
Latin for “pale
are also thalamic nuclei
2. _______________________
2. _______________________
globe”; the
3. _______________________
structure is
Fasciculus – a slender bundle
3. _______________________
traversed by
of fibers
4.
_______________________
4. _______________________
myelinated axons
of other brain
The caudate nucleus,
5. _______________________
5. _______________________
regions, causing
putamen and globus pallidus
6.
_______________________
the light grey (pale)
are components of the basal
6. _______________________
appearance
ganglia
7. _______________________
FIG. 1
PHOTOSERIES 5: Horizontal Cuts at the level of the Pineal Body (Cut A) and ventral level of the Thalamus (Cut B)
PHOTOSERIES 6A: Coronal Cuts Through the Cerebrum (Cuts C to H)
CUT C
2
1
3
4
6
CUT D
4
5
6
9
8
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
8.
_______________________
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
8.
_______________________
9.
_______________________
10. _______________________
10 (on ventral surface)
CUT E
SF
2
1
8
3
7
6
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
8.
_______________________
19
PHOTOSERIES 6A: Coronal Cuts Through the Cerebrum (Cuts C to H)
CUT F
SF
1
2
4
3
5
6
7
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
8.
_______________________
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
8.
_______________________
9.
_______________________
8
CUT G
LV
SF
9
1
2
4
6
LV
3
9
1
7
8 (Ventral Surface)
CUT H
1
10
(outer
surface of
hippocampus)
3
9
III
8
4
7
5
6
10
(outer
surface of
hippocampus)
10. _______________________
Remember, the pulvinar, LGB &
MGB are also thalamic nuclei
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
8.
_______________________
9.
_______________________
10. _______________________
Mastering The Cerebral Coronal Cuts
When studying the coronal cuts, keep in mind the anterior to posterior progression of structures
learned in PS3-5:
Cuts C to E
• As you progress posteriorly, you are observing the evolution of the major striatal/pallidal
components of the basal ganglia (see pg 8 for complete description of basal ganglia) and
the capsules (internal/external/extreme) that separate them
• The globus pallidus is the last structure of the striatal/pallidal basal ganglia to enter, which
occurs around Cut D3/4
• The presence of the optic chiasm indicates that you’re at the tail end of the striatal/pallidal
basal ganglia
Cuts F to H
• As you progress posteriorly, you are observing the evolution of the thalamus and
hippocampal formation
Remember from PS4 that the thalamus (Pv, LGB, MGB etc) is located ventral to the
hippocampal formation; this spatial arrangement is evident in PS6
• The entry of the hippocampal formation in Cut F indicates the end of the major striatal/
pallidal components of the basal ganglia and beginning of the diencephalon (see page 7 for
complete description of the diencephalon)
Taken together, you should note that when components of the striatal/pallidal components of
the basal ganglia are visible, you can not see thalamic nuclei. Conversely, when components
of the thalamus and hippocampal formation are visible, you can not see the striatal/pallidal
region of the basal ganglia. Thus, it is helpful to think to yourself:
“Front of brain – striatal/pallidal basal ganglia; back of brain – hippocampal formation/
thalamus”
Cut C"
The major
components
of the
striatal/
pallidal
basal
ganglia are
visible in
Cuts C to E
Cut D1"
Cut D3"
Cut E2"
Cut F1"
Cut G"
Cut H1"
The
hippocampal
formation and
thalamic
nuclei are
visible after
the optic
chiasm in
Cuts F to H
Cut H4"
Cut I"
Cut E4"
21
PHOTOSERIES 6B: Coronal Cuts Through the Cerebellum (Cuts J to L)
CUT J
1
8
2
3
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
8.
_______________________
7
Fasciculus– a slender bundle of
fibers
Lemniscus– a fiber tract that
terminates at specific nuclei in
the diencephalon
Reticular– forming an intricate
network
4 6
5
CUT K
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
Peduncle– band of neuronal
projections joining different parts
of the brain
C UT L
1
2
4
3
6
5
7 (on ventral surface)
1.
_______________________
2.
_______________________
3.
_______________________
4.
_______________________
5.
_______________________
6.
_______________________
7.
_______________________
22
Mastering The Cerebellar Coronal Cuts
When studying the cerebellar cuts, keep
in mind;
1. The overall shape of the cut
• Cut J is a “W” shape
• Cut K is a “U” shape, where the
brain stem is:
(i) connected to the cerebellum
along the lateral edges
(ii) tight against the ventral surface
of the cerebellum, causing the
ventricle to appear as a narrow slit
• Cut L is also a “U” shape, where the
brain stem is:
(i) not connected to the cerebellum
(ii) ventricle is larger
CUT J
Brain stem
connected to
cerebellum along
lateral edges"
“W” shape!
2. The spatial clustering of nuclei
Learn the order of the nuclei along the
ventral surface of the IV ventricle
• The cerebellar peduncle and
vestibular nucleus were previously
seen in PS4
CUT K
Brain stem
connected to
cerebellum along
lateral edges"
Learn the order of the nuclei along the
midline
• The medial longitudinal fasciculus
and medial lemniscus are located
along the midline in Cuts J and K
Note the location of nuclei located
lateral to the midline
• The reticular formation is in the same
location in all cuts
Remember each cut has a tract that
runs along the ventral surface
• The transverse pontine fibers are
located in the cut through the pons
• The trapezoid body fibers are
located in the cut through the
trapezoid body
• The pyramidal tract was previously
seen in PS2
“U” shape!
CUT L
Brain stem is not
attached to
cerebellum"
“U” shape!
23
Sheep Brain Dissections
Photoseries 1
During this lab we will examine the dorsal, ventral and
lateral surface structures of the sheep brain. By the end
of this class, you should be able to:
- Understand and utilize all basic anatomical terms
- Identify all major gyri and sulci
- Identify the major components of the cerebellum
- Identify all major lateral and ventral structures
Neuroanatomy Laboratory
Dr. Janelle LeBoutillier
Dissection Procedures: Photoseries 1
Neuroanatomy Laboratory
ANATOMY OF THE DISSECTION
In this lab, you will remove the meninges (pia, arachnoid and dura mater)
from the outer surface of the cerebrum and cerebellum. In addition, the
pituitary gland (hypophysis) will be removed from ventral surface of the
brain to expose several cranial nerves.
MATERIALS
• Scissors
• Dissection probe
• Forceps
• Dissection Tray
PROCEDURE
Removal of Meninges on the Cerebrum
Most specimens arrive with dura (see page 29) and arachnoid mater
already removed from the dorsal and lateral surface of the brain. However,
pia mater – a thin, translucent, cellophane-like membrane – remains
adhered to the entire surface of the brain.
1. To begin the process of pia mater removal on the dorsal surface, use your
scissors to make shallow cuts along the entire length of the medial
longitudinal fissure, which is the deep groove located in between the left
and right cerebral hemispheres (see photograph below).
Medial
longitudinal
fissure
Once the pia mater has been cut along the midline, you need to create
similar openings along each sulci using your dissection probe (steps 2-3). "
25
2
Dissection Procedures
2. Place the tip of your probe along a sulcus in the frontal lobe and gently press it
through the pia mater. Once it has been severed, lift the probe out of the
sulcus (see photograph below). You may also use your scissors to cut through
the pia mater along each sulcus to complete this step if you find it easier.
3. Repeat Step 2 along the entire length of each sulcus, working in an anterior to
posterior direction, over the entire dorsal and lateral surface of the brain.
Medial
longitudinal fissure
Frontal lobe
4. Once pia has been severed along each sulcus, insert the smooth outer
edge of the forceps into a sulcus and grasp a loose edge of the pia
mater. Secure the forceps in the closed position and slowly pull the
membrane away from the surface face of the brain (see photograph
below).
5. Repeat step 4, moving from anterior sulci to posterior sulci until all
pia mater has been removed from the dorsal and lateral surface of
the cerebrum.
26
Dissection Procedures
Removal of Meninges on the Cerebellum
1. Place your forceps flat on the surface of the cerebellum. Grasp the pia
mater by squeezing the arms of the forceps into the closed position. Be
careful not to damage the underlying cerebellar tissue during this step.
Cerebellar folia
Note that
cerebellar folia
(gyri on the
surface of the
cerebellum), are
arranged in a
medial-lateral
orientation (i.e.,
extend laterally
from the
midline).
2. Once you have securely grasped the membrane with your forceps, pull
the translucent layer in the lateral direction, away from the midline of the
brain (i.e., the same direction the cerebellar folia are oriented). Do not
pull the membrane along the anterior–posterior axis, as this may
damage the underlying cerebellar tissue.
Cerebellar
hemisphere
Pull meninges in the
lateral direction
Vermis
Cerebellar
hemisphere
3. Repeat Steps 1-2 along the entire length of the vermis and cerebellar
hemispheres until all pia mater has been removed from the cerebellum.
27
Dissection Procedures
Removal of the Pituitary Gland (Hypophysis)
1. Orient your brain so that the ventral surface faces up. Locate the
pituitary gland (hypophysis) – the darker-coloured bulb, located in the
center of the ventral surface, surrounded by dura mater (white, opaque,
ridgid membrane; see photograph below).
2. With your fingers, carefully lift dura at the edges. You will note that it is
attached to the ventral surface of the brain by several cranial nerves (see
table on page 35 for complete list of cranial nerves and their points of
attachment).
Dura mater
Pituitary Gland
(Hypophysis)
3. Using your scissors, snip the cranial nerves as close to the dura mater as
possible (this will preserve the integrity of each nerve for closer examination
in Photoseries 2). Repeat for each nerve until the dura mater and pituitary
gland (hypophysis) can be lifted off the brain without any resistance. Once
removed, the cranial nerves should be visible.
Cut cranial nerves
closest to dura
ANATOMY OF DISSECTED SAMPLE
Your assigned sheep brain now has its meninges and hypophysis removed.
The dorsal, lateral and ventral surface of the cerebrum is now exposed, as
well as the folia of the cerebellum. The cranial nerves are also visible.
28
Dorsal View with Dura Mater
Dura mater
mmb
Ventral View with the Hypophysis
Pituitary gland
mmb
Dura mater
Periamygdaloid cortex (Uncus)
mmb
mmb
29
Dorsal View of Cerebellum
Medial longitudinal fissure
Cerebellar hemisphere
Spinal cord
mmb
mmb
mmb
Cerebellar hemisphere
mmb
Cerebrum
mmb
Dorsal View with Arteries
Cerebellar hemisphere
Spinal cord
Vermis
mmb
mmb
mmb
Cerebrum
mmb
30
Dorsal View with Gyri and Sulci
Ectomarginal gyrus
Marginal gyrus
Endomarginal gyrus
mmb
mmb
mmb
Endomarginal sulcus
mmb
Ectomarginal sulcus
Marginal sulcus
mmb
mmb
Dorsal View with Gyri and Sulci
Rostral suprasylvian gyrus
Ansate sulcus
Coronal sulcus
Precoronal gyrus
mmb
Caudal suprasylvian gyrus
mmb
mmb
mmb
mmb
31
Dorsal View with Gyri and Sulci
Rostral suprasylvian gyrus
mmb
Ectomarginal gyrus
mmb
Caudal ectosylvian gyrus
Precoronal gyrus
Coronal sulcus
mmb
mmb
Caudal suprasylvian gyrus
mmb
Marginal gyrus
mmb
mmb
Endomarginal gyrus
mmb
Endomarginal sulcus
Ansate sulcus
mmb
mmb
Marginal sulcus
Medial longitudinal fissure
mmb
Suprasylvian sulcus
mmb
Ectomarginal sulcus
mmb
mmb
Dorsal View with Gyri and Sulci
Coronal sulcus
mmb
Ansate sulcus
mmb
6
Precoronal gyrus
32
Lateral View
Rhinal fissure
mmb
Sylvian sulcus
mmb
Diagonal sulcus
mmb
Presylvian sulcus
Pyriform lobe
mmb
mmb
Lateral olfactory tract
Periamygdaloid cortex (Uncus)
mmb
mmb
Presylvian gyrus
mmb
33
Sheep Brain Dissections
Photoseries 2
During this lab we will examine the location and point of
attachment of each cranial nerve and sensory tracts.
By the end of this lab you should be able to:
- Identify all 12 cranial nerves
- Know the type of information each nerve carries
(sensory, motor or both)
- Distinguish between nerves and tracts
*Note: The hypoglossal nerve is not pictured in this Photoseries, but students
are still responsible for knowing its location (see diagram on page 13) and type
of information it carries (see table on page 35).
Neuroanatomy Laboratory
Dr. Janelle LeBoutillier
Ventrolateral View
Pons
Periamygdaloid cortex (Uncus)
Presylvian sulcus
mmb
mmb
Ventral median fissure
mmb
mmb
Olive
Lateral olfactory tract
Sylvian sulcus
mmb
mmb
Trapezoid body
mmb
mmb
Pyriform lobe
mmb
35
Ventral View
Periamygdaloid cortex (Uncus)
Optic tract
Olive
mmb
Trapezoid body
mmb
mmb
mmb
Pyramidal tract
Optic chiasm
mmb
mmb
Olfactory tubercle
mmb
Ventral median fissure
Lateral olfactory tract
Pons
mmb
Pyriform lobe
mmb
mmb
mmb
Ventral View
Oculomotor nerve
Pons
Pyramidal tract
Ventral median fissure
mmb
Lateral olfactory tract
mmb
mmb
mmb
mmb
Mammillary body
mmb
Olfactory bulb
mmb
36
Ventral View with Meninges
Mammillary body
Infundibulum
Abducens nerve
Olfactory tubercle
mmb
Olfactory bulb
Spinal accessory nerve
Medial olfactory tract
mmb
Vagus nerve
Lateral olfactory tract
mmb
Glossopharyngeal nerve
Tuber cinereum
Trigeminal nerve
Ventral View with Cranial Nerves
Infundibulum
mmb
Mammillary body
mmb
Trigeminal nerve
Oculomotor nerve
Tuber cinereum
mmb
mmb
mmb
Facial nerve
mmb
Vestibulocochlear nerve
mmb
37
Ventral View with Cranial Nerves
Optic nerve
mmb
Infundibulum
mmb
mmb
Oculomotor nerve
mmb
Mammillary body
Tuber cinereum
mmb
mmb
Spinal accessory nerve
Trigeminal nerve
Vestibulocochlear nerve
mmb
Facial nerve
mmb
mmb
mmb
Lateral View with Cranial Nerves
Oculomotor nerve
Optic nerve
mmb
Pons
mmb
Spinal accessory nerve
mmb
mmb
Olive
Periamygdaloid cortex (Uncus)
mmb
Facial nerve
Trigeminal nerve
mmb
mmb
mmb
Vestibulocochlear nerve
mmb
38
Lateral View with Cranial Nerves
Tuber cinereum
mmb
Mammillary body
mmb
Abducens nerve
Trigeminal nerve
mmb
mmb
Vestibulocochlear nerve
Facial nerve
mmb
mmb
Ventral View with Cranial Nerves
Oculomotor nerve
mmb
Optic tract
mmb
Optic chiasm
mmb
Medial olfactory tract
Olfactory tubercle
Trochlear nerve
mmb
mmb
mmb
Lateral olfactory tract
mmb
39
Ventral View with Trochlear Nerve
Infundibulum
mmb
mmb
Tuber cinereum
Oculomotor nerve
mmb
Rhinal fissure
Trochlear nerve
mmb
mmb
mmb
Lateral-Ventral View of Cranial Nerves
Trochlear nerve
Oculomotor nerve
mmb
Trigeminal nerve
mmb
mmb
Pons
mmb
Trapezoid body
mmb
40
Sheep Brain Dissections
Photoseries 3
During this lab we will make a midsagittal cut, revealing
structures located along the midline of the brain. By the
end of this lab you should be able to identify:
- Components of the cerebellum
- Structures within the diencephalon, mesencephalon
and brain stem
- Components of the corpus callosum
- Major gyri and sulci along the midline
- Components of the ventricular system
Neuroanatomy Laboratory
Dr. Janelle LeBoutillier
Dissection Procedures: Photoseries 3
Neuroanatomy Laboratory
ANATOMY OF THE DISSECTION
In this lab, a midsagittal cut will be made to expose midline structures,
including the corpus callosum, diencephalon, brain stem and vermis of the
cerebellum.
MATERIALS
• Dissection tray
• Dissection knife (TA will provide and assist as necessary)
PROCEDURE
1. Turn your dissection tray upside down, exposing the flat metal surface
which you will use as your cutting surface. Position your assigned brain in
the center with the dorsal surface facing up (see photograph below).
2. Work with your partner to complete the dissection: one person should
stand on one side of the lab bench, closest to the frontal lobe, and
stabilize the brain by firmly holding the cerebral and cerebellar
hemispheres with their fingers. The other lab partner should stand on the
opposite side of the lab bench and position the knife (see photograph
below).
3. Place the dissection knife in the medial longitudinal fissure, and ensure
that it is oriented perpendicular (90 degrees) to the surface of the
dissection tray. Remember to keep your fingers away from the midline
where the cut will be made (see photograph below).
CAUTION: Keep
your fingers away
from the midline
where the brain is
being bisected.
42
Dissection Procedures
4. Ensure that the cerebellum and spinal cord are lined up with the blade
along the midline (see photograph below). The person stabilizing the
brain needs to maintain the brain in this exact position while the cut is
being made.
Ensure that the
the cerebellum
and spinal cord
are appropriately
lined up with the
dissection knife
along the midline
of the brain.
5. Apply even pressure down the full length of the blade, and slice downwards
in one smooth motion. Do not make sawing motions back and forth, as this
may damage the tissue along the midline; the blade is sufficiently sharp to
slice right through the brain in one smooth motion.
6. Once the blade connects with the surface of the dissection tray, slowly
pull the dissection knife towards you, keeping it perpendicular to the tray
at all times.
1
2
Pull dissection
knife towards you
Apply pressure
downwards
7. You can now pull apart the two hemispheres to reveal midline structures.
If the meninges have not been thoroughly removed, the hemispheres
may remain slightly connected, particularly along the ventral surface; if
this occurs, use your scalpel to sever the connected tissue.
43
Dissection Procedures
8. Before proceeding with the content of Photoseries 3, clean the metal
surface of the dissection tray using paper towels and 70% ethanol.
Once cleaned, you can turn over the dissection tray, place your
bisected sheep brain inside, and examine midline structures.
Clean metal
surface of
dissection tray
before
proceeding with
the content of
Photoseries 3.
ANATOMY OF THE DISSECTED SAMPLE
After performing this cut along the midline, you will have separated the left
and right hemispheres. The corpus callosum, ventricular system, thalamus,
hypothalamus, pineal body, vermis and superior+inferior colliculi will be
visible.
44
Lateral View with M eninges
Sylvian sulcus
Rhinal fissure
Paraflocculus
Paramedian lobule
mmb
mmb
mmb
mmb
Spinal accessory nerve
mmb
Flocculus
Lateral olfactory tract
mmb
Abducens nerve
mmb
Olfactory bulb
mmb
mmb
Sagittal Section Showing Anterior Lobe of the Cerebellum
Simplex
Primary fissure
mmb
mmb
Tuber vermis
Culmen
Centralis
mmb
mmb
mmb
mmb
Pyramis
Lingula
mmb
mmb
Flocculus
Cut surface of pons
mmb
mmb
Paraflocculus
mmb
45
Lateral Cerebellum
Tuber vermis
Pyramis
Ansiform lobule
mmb
mmb
mmb
Uvula
mmb
Paramedian lobule
mmb
Paraflocculus
mmb
Flocculus
mmb
Caudal View of the Cerebellum
Tuber vermis
mmb
Paramedian lobule
Pyramis
mmb
mmb
Paraflocculus
Uvula
mmb
mmb
Cut surface of spinal cord
mmb
46
Dorsal View of the Rostral Cerebellum
Simplex
Tuber vermis
mmb
mmb
Ansiform lobule
Primary fissure
mmb
mmb
Culmen
mmb
Paraflocculus
mmb
Rostral View of the Cerebellum
Tuber vermis
mmb
Ansiform lobule
Simplex
mmb
mmb
Paraflocculus
Primary fissure
Culmen
mmb
mmb
mmb
Centralis
mmb
Flocculus
Lingula
mmb
mmb
IV ventricle
mmb
Cut surface of pons
mmb
47
Midsagittal Section of the Cerebellum
Simplex
mmb
Primary fissure
Tuber vermis
mmb
mmb
Pyramis
mmb
Uvula
Centralis
Lingula
mmb
mmb
mmb
Nodulus
mmb
Sagittal Section with the Cerebellum
Primary fissure
mmb
Simplex
Culmen
Centralis
Lingula
mmb
mmb
mmb
mmb
Nodulus
mmb
48
Midsagittal Section of the Cerebellum
Simplex
Tuber vermis
mmb
Primary fissure
mmb
Culmen
Pyramis
mmb
Centralis
mmb
mmb
mmb
Uvula
Cerebral aqueduct
mmb
mmb
Lingula
mmb
IV ventricle
Nodulus
mmb
mmb
Midsagittal Section
Fornix
mmb
Genual sulcus
Posterior commissure
mmb
Cingulate gyrus
Superior colliculus
Inferior colliculus
mmb
mmb
mmb
mmb
Genual gyrus
Mammillary body
mmb
mmb
Hypothalamus
mmb
Anterior commissure
Subcallosal gyrus
mmb
mmb
49
Midsagittal Section
Body of corpus callosum
III ventricle
Splenium of corpus callosum
Superior colliculus
mmb
mmb
Genu of corpus callosum
mmb
mmb
mmb
Lateral ventricle
Interventricular foramen
mmb
Caudate nucleus
Inferior colliculus
mmb
Pineal body
mmb
mmb
mmb
Midsagittal Section with Arteries
Body of corpus callosum
Stria medullaris
mmb
mmb
Septum pellucidum
Habenula
Choroid plexus
mmb
mmb
mmb
Genu of corpus callosum
Mammillary body
mmb
Hypothalamus
Optic chiasm
mmb
mmb
mmb
50
Midsagittal Section
Thalamus
III ventricle
Cingulate gyrus
mmb
Cerebral aqueduct
mmb
mmb
mmb
Massa intermedia
mmb
Septum pellucidum
mmb
IV ventricle
Genual gyrus
mmb
mmb
Midbrain
Pons
Interventricular foramen
Spinal cord
mmb
mmb
mmb
Medulla
Midsagittal Section Of Epithalamus
Habenula
Stria medullaris
Thalamus
Choroid plexus
mmb
mmb
Pineal body
mmb
mmb
Posterior commissure
mmb
Massa intermedia
mmb
mmb
51
Midsagittal Section of Diencephalon and Brain Stem
Thalamus
Fornix
mmb
mmb
Midbrain
mmb
Medulla
Pons
Massa intermedia
mmb
mmb
mmb
Hypothalamus
mmb
Dorsal Sagittal Section
Alveus
mmb
Choroid plexus
mmb
Genual gyrus
Pineal body
mmb
mmb
52
Sheep Brain Dissections
Photoseries 4
During this lab we will perform a hippocampal dissection,
which will reveal numerous components of the
diencephalon. By the end of this lab you should be able
to identify:
- Brain stem nuclei
- Arteries of the brain
- Components of the hippocampal formation
- Components of the diencephalon
- Major tracts and capsules
Depth
of the
cut
53
Dissection Procedures: Photoseries 4
Neuroanatomy Laboratory
ANATOMY OF THE DISSECTION
In this lab, the cerebral cortex will be removed from one hemisphere
of your assigned sheep brain to expose the hippocampal formation.
MATERIALS
• Scalpel
• Forceps
• Scissors
• Dissection probe
• Dissection tray
PROCEDURE
Exposing the Hippocampal Formation
1. With your scalpel, make an incision through the splenium of the
corpus callosum (CC). Extend the incision in a posterior
direction, cutting through the occipital lobe (see below for
depth and location of this first cut).
Splenium
of the CC
Initial incision
(Midsagittal view)
Occipital
lobe
Extend incision posteriorly through
the occipital lobe
2. Continue cutting in a smooth motion along the circumference
of the cortex. Cut all the way around the brain – through the
occipital lobe, border of parietal-temporal lobe and frontal
lobe – until you return to the location of your first incision. Your
goal is to remove the top half of the cerebral cortex and
expose subcortical structures below (see photos on the next
page for guidance).
54
Dissection Procedures
1
Parietal lobe
2
Temporal
lobe
Cerebellum
Incision through occipital lobe
(Caudal view)
3
Temporal
lobe
Parietal
lobe
Frontal
lobe
Incision through frontal lobe
(Anterior view)
Incision through parietal lobe
(Lateral view)
Parietal
lobe
4
Frontal
lobe
Incision through frontal lobe
(Midsagittal view)
5
CAUTION: Keep
your fingers away
from the blade of
the scalpel while
performing this
dissection.
Splenium of CC
Return to location of initial incision
(Midsagittal view)
55
Dissection Procedures
3. Remove the top half of the brain that you have just bisected. You
should see the dorsal aspect of the hippocampal formation
surrounded by an opening, which is the lateral ventricle (see
photo below).
Removing Cortical Tissue Surrounding the Hippocampal formation
1. Locate the lateral ventricle (the hollow “space”) along the caudal
edge of the hippocampal formation. Using your forceps, grasp the
cortical tissue and carefully peel the tissue away from the
hippocampal formation (see photos below).
Cortex to be
removed
Hippocampus
Cortex to be
removed
Lateral Ventricle
2. Continue to remove all remaining cortex with your forceps (and
scalpel if necessary) until the entire ”horn" of the hippocampal
formation is revealed. Note that the hippocampus is only attached
at the midline by the fornix, so try not to sever this point of
attachment.
56
Dissection Procedures
ANATOMY OF THE DISSECTED SAMPLE
Once the surrounding cortex has been removed, the entire “horn” of
the hippocampal formation should be visible.
Dorsal view of Hippocampal
Formation
Hippocampus
Grasp the dorso-lateral tip of the hippocampal formation (labelled
below) and gently lift up the “horn”. The ventral surface of the
hippocampal formation, as well as several thalamic nuclei, will be visible.
Lateral view with Hippocampal
Formation
Ventral view of Hippocampal
Formation
Dorso-lateral tip of Hippocampal formation
Lateral view with Hippocampal
Formation Removed
Thalamic nuclei
57
Lateral View with Arteries
Rhinal fissure
mmb
Paraflocculus
mmb
Paramedian lobule
Middle cerebral artery
Flocculus
mmb
Periamygdaloid cortex (Uncus)
mmb
mmb
mmb
mmb
Ventral View with Arteries
Posterior cerebral artery
Basilar artery
Anterior cerebral artery
mmb
mmb
mmb
Posterior communicating artery
mmb
Middle cerebral artery
mmb
58
Circle of Willis
Posterior communicating artery
mmb
Basilar artery
mmb
Posterior cerebral artery
Middle cerebral artery
mmb
mmb
Pyriform lobe
mmb
Dorsal View of Brain Stem Nuclei
Vagal nucleus
Obex
mmb
IV ventricle
mmb
Gracile nucleus
mmb
Cerebellar peduncle
Cuneate nucleus
mmb
mmb
mmb
Vestibular nucleus
mmb
59
Dorsal View of the Hippocampal Formation and Caudate Nucleus
Superior colliculus
Inferior colliculus
mmb
mmb
IV ventricle
mmb
Caudate nucleus
Septum pellucidum
Vagal nucleus
Obex
mmb
mmb
mmb
Gracile nucleus
mmb
Cuneate nucleus
mmb
mmb
Vestibular nucleus
mmb
Genu of corpus callosum
Dorsal fornix
Alveus
mmb
mmb
mmb
Dorsal View of IV Ventricle
Inferior colliculi
Cerebellar peduncle
IV ventricle
mmb
Superior colliculi
mmb
mmb
mmb
60
Dorsal View of Hippocampal Formation
Vestibular nucleus
Obex
mmb
mmb
Pineal body
Vagal nucleus
Gracile nucleus
mmb
Genu of corpus callosum
mmb
mmb
mmb
Cuneate nucleus
mmb
Dorsal fornix
mmb
Fimbria
mmb
Dorsal View of Hippocampal Formation
Septal nucleus
Fimbria
Alveus
Superior colliculi
Caudate nucleus
Dorsal fornix
61
Hippocampal Formation
Fimbria
Alveus
Superior colliculi
mmb
mmb
mmb
Pineal body
mmb
Caudal View of Midbrain
Pulvinar
Alveus
mmb
Pineal body
mmb
mmb
Superior colliculi
IV ventricle
Inferior colliculi
mmb
mmb
mmb
62
Lateral View of Hippocampal Formation
Splenium of corpus callosum
Pineal body
Superior colliculus
mmb
Caudate nucleus
mmb
mmb
Genu of corpus callosum
mmb
mmb
Fimbria
mmb
Lateral ventricle
Alveus
mmb
mmb
Dorsal View of Detached Hippocampal Formation
Alveus
Fimbria
mmb
mmb
63
Ventral View of the Hippocampal Formation
Hippocampal fissure
mmb
Dentate gyrus
mmb
Fimbria
mmb
Ventral View of the Hippocampal Formation
Dentate gyrus
Hippocampal fissure
mmb
mmb
Fimbria
mmb
64
Dorsal View of the Diencephalon and Striatum
Fimbria
mmb
Habenula
Stria medullaris
mmb
mmb
Corona radiata
Superior colliculus
mmb
mmb
Medial geniculate body
Caudate nucleus
mmb
mmb
Lateral geniculate body
Pulvinar
mmb
mmb
Ventral View of Diencephalon
Lateral geniculate body
Optic tract
mmb
mmb
Trapezoid body
mmb
Pyramidal tract
Pons
Optic chiasm
mmb
Mammillary body
mmb
mmb
mmb
65
Lateral View of Midbrain
Superior colliculus
Pulvinar
mmb
mmb
Lateral geniculate body
Medial geniculate body
Inferior colliculus
mmb
mmb
mmb
Optic tract
mmb
Lateral View of Midbrain
Pulvinar
Superior colliculus
Inferior colliculus
Medial geniculate body
Lateral geniculate body
mmb
mmb
mmb
Optic tract
mmb
mmb
mmb
Mammillary body
mmb
Optic chiasm
mmb
66
Lateral View of Midbrain
Superior colliculus
Pulvinar
Lateral geniculate body
mmb
mmb
Ansiform lobule
mmb
mmb
Paramedian lobule
mmb
Paraflocculus
Medial geniculate body
mmb
Flocculus
Olfactory bulb
mmb
mmb
mmb
Pons
mmb
Lateral View of Internal Capsule
Inferior colliculus
mmb
Pons
Superior colliculus
Corona radiata
mmb
mmb
Internal capsule
mmb
Mammillary body
Optic chiasm
mmb
mmb
mmb
Optic tract
mmb
67
Lateral View of Internal Capsule
Optic radiations
Corona radiata
mmb
Superior colliculus
mmb
Massa intermedia
Optic chiasm
Internal capsule
mmb
mmb
IV ventricle
mmb
mmb
mmb
Lateral View of Internal Capsule
Pulvinar
Thalamus
mmb
mmb
Pineal body
Massa intermedia
mmb
mmb
Inferior colliculus
mmb
68
Ventral Cerebrum
Splenium of corpus callosum
mmb
Body of corpus callosum
mmb
Genu of corpus callosum
Cerebrum
mmb
mmb
69
Sheep Brain Dissections
Photoseries 5
During this lab we will make a transverse (horizontal) cut
at the level of the pineal body (Cut A) and ventral level of
the thalamus (Cut B). By the end of this lab you should
be able to identify dorsal and ventral components of the
diencephalon, basal ganglia, limbic system as well as
major capsules + tracts.
Midsagittal Cut
Cut A
Cut B
A1
A2
B1
B2
70
Dissection Procedures: Photoseries 5
Neuroanatomy Laboratory
ANATOMY OF THE DISSECTION
In this lab, two horizontal (transverse) cuts will be made:
• Cut A – sectioned at the level of the pineal body to expose the
basal ganglia and dorsal thalamic nuclei
• Cut B – sectioned through the ventral region of the thalamus to
reveal thalamic nuclei, limbic structures and the complete
ventricular system
MATERIALS
• Dissection tray
• Dissection knife (TA will provide and assist as necessary)
PROCEDURE
Horizontal (transverse) Cut A
1. Turn the dissection tray upside down, exposing the flat metal
surface. Place one hemisphere of your brain on the metal surface,
orientated with the midsagittal surface facing up (see photograph
below).
2. Work with your partner to complete this dissection: one person
should stand on one side of the lab bench and secure the the brain
in the position shown below. The other person, standing on the
opposite side of the lab bench, should position the dissection knife.
3. Place the dissection knife perpendicular to the surface of the
dissection tray, positioned at the level of the pineal body (shown in
photograph below). Apply even pressure down the full length of
the blade, and slice downwards in one smooth motion. Do not
make sawing motions back and forth, as this may damage the
tissue; the blade is sufficiently sharp to slice right through the brain in
one smooth motion.
Cut A
CAUTION: Keep
your fingers away
from the blade of
the knife.
Pineal
body
71
Dissection Procedures
4. Once contact has been made with the metal surface of the
dissection tray, slowly pull the knife towards you and allow the two
pieces of the brain to separate. The structures at the level of the
pineal body level should be visible (see photograph below).
Cut A
Horizontal (transverse) Cut B
1. Take the ventral portion of the hemisphere sectioned in Cut A, and
orient the tissue on the metal surface of the dissection tray as shown
below. Caution: you are now working with a thinner piece of brain
tissue, and therefore need to be more cautious when stabilizing the
brain and positioning the knife.
2. Align the knife along the ventral aspect of the cerebellum, above
the brain stem (see photograph below).
Cut B
Brain stem
Cerebellum
CAUTION: In Cut B
you are dissecting
a smaller tissue
sample – ensure
that your fingers
are appropriately
positioned away
from the blade of
the knife.
72
Dissection Procedures
3. Once again, push the knife through the brain tissue until you
contact the surface of the dissection tray. Slowly pull the knife
towards you and allow the two sections to separate.
Cut B
Clean metal
surface of
dissection tray
before
proceeding with
the content of
Photoseries 5.
4. Before proceeding with the content of Photoseries 5, clean the metal
surface of the dissection tray with 70% ethanol. Once cleaned, you
can turn over the dissection tray, place your bisected sheep brain
inside, and examine transverse structures.
ANATOMY OF THE DISSECTED SAMPLE
After performing these horizontal (transverse) cuts, dorsal and ventral
components of the basal ganglia, diencephalon and limbic system
will be visible.
73
(A1) At the Level of the Pineal Body
Lateral ventricle
Lateral geniculate body
Dentate gyrus
mmb
mmb
mmb
Superior colliculus
Pulvinar
mmb
mmb
Caudate nucleus
mmb
Stria medullaris
mmb
Paraflocculus
Habenula
mmb
mmb
Pineal body
mmb
(A2) At the Level of the Pineal Body
Internal capsule
Caudate nucleus
Subcallosal fasciculus
mmb
mmb
Putamen
mmb
Septal nucleus
mmb
III ventricle
mmb
mmb
Medial thalamic nucleus
Lateral ventricle
mmb
mmb
Genu of corpus callosum
mmb
Septum pellucidum
mmb
Anterior thalamic nucleus
Ventral thalamic nucleus
mmb
mmb
74
(A2) At the Level of the Pineal Body
Dentate gyrus
Alveus
Septal nucleus
Paraflocculus
Pineal body
Genu of corpus callosum
Pulvinar
Septum pellucidum
Lateral geniculate body
(A3) Ventral to the Pineal Body
Fimbria
mmb
Dentate gyrus
External capsule
Alveus
mmb
Globus pallidus
mmb
mmb
mmb
Cut surface of superior colliculus
mmb
75
(A3) Ventral to the Pineal Body
Internal capsule
Caudate Nucleus
mmb
mmb
Cut surface of superior colliculus
Putamen
mmb
mmb
(B1) Ventral Level of the Thalamus
Fimbria
Amygdala
mmb
mmb
Dentate gyrus
Caudate nucleus
mmb
mmb
III Ventricle
mmb
Central gray
Cerebral aqueduct
Genu of corpus callosum
mmb
mmb
mmb
Septal nucleus
Ventral thalamic nucleus
mmb
mmb
Habenulo-interpeduncular tract
mmb
76
(B1) Ventral Level of the Thalamus
Ventral thalamic nucleus
mmb
Habenulo-interpeduncular tract
Globus pallidus
Genu of corpus callosum
mmb
mmb
mmb
Lateral geniculate body
mmb
Medial geniculate body
mmb
(B2) Ventral to the Corpus Callosum
External Capsule
Putamen
mmb
Globus pallidus
Internal capsule
mmb
mmb
Amygdala
Caudate nucleus
mmb
mmb
Lateral geniculate body
Lateral ventricle
mmb
mmb
Medial geniculate body
Habenulo-interpeduncular tract
Septohypothalamic and septotubercular tracts
mmb
mmb
Ventral thalamic nucleus
Fornix
mmb
mmb
mmb
III ventricle
mmb
77
Structures seen in both Cuts A & B:
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
Structures specific to Cut B:
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
________________________________
Cut B2
Structures specific to Cut A:
Cut A2
PHOTOSERIES 5 IN-LAB ACTIVITY: Determine with structures are specific to Cut A, Cut B and are common to both
Sheep Brain Dissections
Photoseries 6A
During this lab we will make coronal cuts throughout the
cerebrum (cerebral hemispheres).
C
OB
OTr
D
E
F
G
H
Cerebral cuts
I
OTb
OC
Pons
MB
TB
Med
CP
C.
Caudal to Olfactory
Bulbs
D.
Olfactory Tubercles
E.
Optic Chiasm
F.
Caudal to Optic
Chiasm
G.
Mammillary Body
H.
Cerebral Peduncles
I.
Rostral Pons
Neuroanatomy Laboratory
Dr. Janelle LeBoutillier
Dissection Procedures: Photoseries 6A
Neuroanatomy Laboratory
ANATOMY OF THE DISSECTION
In this lab, seven coronal cuts through the cerebrum will be made
through the following ventral surface structures:
Cut G – through mammillary bodies
Cut C – caudal to olfactory bulbs
Cut H – through cerebral peduncles
Cut D – through olfactory tubercles
Cut I – through the rostral pons
Cut E – through optic chiasm
Cut F – Caudal to optic chiasm
MATERIALS
• Dissection tray
• Dissection knife (TA will provide and assist as necessary)
• Scalpel
PROCEDURE
1. Turn the dissection tray upside down, exposing the flat, metal surface.
Place one hemisphere of your assigned brain on the metal surface,
orientated with the ventral surface facing up (see photograph
below).
2. Work with your partner to complete this dissection: one person should
stand on one side of the lab bench and hold the the brain in place.
The other person, standing on the opposite side of the lab bench,
should position the dissection knife.
3. Place the dissection knife caudal to the olfactory bulbs, keeping the
blade perpendicular to the surface of the dissection tray (shown in
photograph below). Push the knife straight down in one smooth
motion.
4. As the blade touches the tray, slowly pull the knife towards you and
let the two pieces of brain separate. Your cut should be similar to that
shown below.
Olfactory
bulb
Cut C
)+"
Dissection Procedures
5. To complete Cut E, repeat steps 2-4, with the knife positioned at
the level of the optic chiasm.
Cut E
6. Similarly, repeat steps 2-4 at the level of the cerebral peduncles (Cut H).
Clean metal surface
of dissection tray
before proceeding
with the content of
Photoseries 6A.
Cut H
ANATOMY OF THE DISSECTED SAMPLE
After performing these coronal cuts through the cerebrum, all major
cortical and subcortical structures will be visible, including several
ventricles, tracts, commissures and capsules.
81
(C1) Caudal to Olfactory Bulbs
Corona radiata
Cingulum
Lateral ventricle
Subcallosal fasciculus
Claustrum
Caudate nucleus
External capsule
Septohypothalamic and septotubercular tracts
Putamen
(C2) Caudal to Olfactory Bulbs
"
Corona radiata
Cingulum
Genu of corpus callosum
Caudate nucleus
Putamen
Lateral olfactory tract
Septohypothalamic and septotubercular tracts
82
(D1) Through Olfactory Tubercles
Body of corpus callosum
Caudate nucleus
Subcallosal fasciculus
Extreme capsule
Internal capsule
Claustrum
Putamen
External capsule
Anterior commissure
Olfactory tubercle
Septohypothalamic and septotubercular tracts
(D2) Through Olfactory Tubercles
Caudate nucleus
Subcallosal fasciculus
Extreme capsule
External capsule
Internal capsule
Lateral olfactory tract
Anterior commissure
Olfactory tubercle
83
(D3) Through Olfactory Tubercles
Extreme capsule
mmb
Subcallosal fasciculus
External capsule
mmb
mmb
Putamen
mmb
Internal capsule
mmb
Globus pallidus
Claustrum
mmb
mmb
(D4) Through Olfactory Tubercles
Cingulum
mmb
Septum pellucidum
Septal nucleus
Globus pallidus
mmb
mmb
mmb
Olfactory tubercle
mmb
Lateral olfactory tract
mmb
84
(E1) Through Optic Chiasm
Body of corpus callosum
Lateral ventricle
Caudate nucleus
Extreme capsule
Septal nucleus
External capsule
Putamen
Claustrum
Globus pallidus
Preoptic area
Internal capsule
Optic chiasm
Column of fornix
(E2) Through Optic Chiasm
Subcallosal fasciculus
Extreme capsule
Caudate nucleus
Claustrum
Internal capsule
Putamen
Globus pallidus
Optic chiasm
85
(E3) Through Optic Chiasm
Body of corpus callosum
mmb
Caudate nucleus
mmb
Extreme capsule
External capsule
mmb
mmb
Claustrum
Optic chiasm
mmb
mmb
Globus pallidus
mmb
(F1) Through Optic Chiasm
Body of corpus callosum
Lateral ventricle
Fornix
Fimbria
Subcallosal fasciculus
Extreme capsule
Caudate nucleus
Anterior thalamic nucleus
Amygdala
Claustrum
Fornix
External capsule
Hypothalamus
Optic Chiasm
Putamen
86
(F2) Through Optic Chiasm
Fornix
Fimbria
Cingulum
Subcallosal fasciculus
Internal capsule
Optic tract
III Ventricle
Hypothalamus
(G1) Anterior to Mammillary Body
Subcallosal fasciculus
Fornix
III ventricle
mmb
mmb
mmb
Stria medullaris
mmb
Mammillothalamic tract
Fornix
Choroid plexus
mmb
mmb
mmb
Mammillary body
mmb
Optic tract
mmb
87
(G2) Through Mammillary Body
Fornix
Fimbria
mmb
Subcallosal fasciculus
mmb
mmb
Medial thalamic nucleus
Stria medullaris
mmb
mmb
Ventral thalamic nucleus
III ventricle
mmb
mmb
Fornix
mmb
Mammillary body
mmb
Optic tract
mmb
(G3) Through Mammillary Body
Splenium of corpus callosum
mmb
Subcallosal fasciculus
Fornix
Dentate gyrus
mmb
mmb
mmb
Fimbria
Habenula
mmb
Medial thalamic nucleus
mmb
mmb
Ventral thalamic nucleus
Optic tract
mmb
mmb
Mammillothalamic tract
mmb
Fornix
mmb
III ventricle
mmb
88
(H1) Through Cerebral Peduncles
Pineal body
Subcallosal fasciculus
mmb
mmb
Posterior commissure
Dentate gyrus
mmb
mmb
Lateral geniculate body
mmb
Medial geniculate body
Alveus
mmb
mmb
Crus cerebri
Substantia nigra
mmb
Midbrain reticular formation
mmb
mmb
(H2) Through Cerebral Peduncles
Cingulum
mmb
Subcallosal fasciculus
Splenium of corpus callosum
mmb
mmb
Pulvinar
Pineal body
mmb
mmb
Lateral geniculate body
mmb
Medial geniculate body
Crus cerebri
Midbrain reticular formation
mmb
Posterior commissure
mmb
mmb
mmb
Substantia nigra
mmb
89
(H3) Through the Cerebral Peduncles
Dentate gyrus
Pineal body
mmb
mmb
Posterior commissure
mmb
Pulvinar
mmb
Lateral geniculate body
Medial geniculate body
mmb
Alveus
mmb
Midbrain reticular formation
mmb
mmb
(H4) Through Cerebral Peduncles
Splenium of corpus callosum
mmb
Subcallosal fasciculus
Superior colliculus
mmb
mmb
Dentate gyrus
Posterior commissure
mmb
Alveus
Lateral ventricle
mmb
mmb
mmb
90
(I1) Through the Rostral Pons
Optic radiations
Superior colliculus
mmb
mmb
Inferior colliculus
Central gray
mmb
mmb
mm
b
Cerebral aqueduct
mmb
(I2) Through the Rostral Pons
mmb
Superior colliculus
mmb
Inferior colliculus
Rostral pons
mmb
mmb
91
Sheep Brain Dissections
Photoseries 6B
During this lab we will make coronal cuts throughout the
cerebellum.
Cerebellar cuts
J K
OB
OTr
L
J.
Mid-Pons
K.
Rostral medulla
L.
Glossopharyngeal
nerve
OTb
OC
Pons
MB
TB Medulla
CP
Neuroanatomy Laboratory
Dr. Janelle LeBoutillier
Dissection Procedures: Photoseries 6B
Neuroanatomy Laboratory
ANATOMY OF THE DISSECTION
In this lab, three cerebellar coronal cuts will be made through the
following ventral surface structures:
• Cut J – though mid-pons
• Cut K – through rostral medulla
• Cut L – at the glossopharyngeal nerve
MATERIALS
• Dissection tray
• Dissection knife (TA will provide and assist as necessary)
• Scalpel
PROCEDURE
1. Turn the dissection tray upside down, exposing the flat metal
surface. Place the uncut cerebellum remaining from Photoseries
6A on the metal surface, orientated with the ventral surface
facing up (see photograph on the following page).
2. Work with your partner to complete this dissection: one person
should stand on one side of the lab bench and hold the the
brain in place. The other person, standing on the opposite side
of the lab bench, should position the dissection knife.
3. Place the dissection knife over the middle of the pons, keeping
the blade perpendicular to the surface of the dissection tray
(shown in photograph on the next page). Push the knife straight
down in one smooth motion. Caution: you are now working with
a small piece of brain tissue, therefore be cautious when
stabilizing the brain and positioning the knife.
93
Dissection Procedures
4. When the blade touches the tray, slowly pull the knife towards you
and let the two pieces of brain separate. Your cut should be similar
to that shown below.
CAUTION: You are working
with a small tissue sample –
ensure that your fingers are
appropriately positioned
away from the blade of the
knife.
Cut J
CUT J
5. The next cerebellar cut (Cut K) is made along the division line
between the pons and the trapezoid body, as shown below.
Repeat steps 2-4 to complete this cut.
Cut K
Clean metal surface of
dissection tray before
proceeding with the content
of Photoseries 6B.
CUT K
.
6. The final Cut L is made along the division line between the
trapezoid body and the rest of the medulla (no photograph
shown). Note: this coronal section will likely separate into two
pieces: (1) the cerebellar folia and (2) the 'kidney bean' shaped
medulla.
ANATOMY OF THE DISSECTED SAMPLE
After performing these coronal cuts through the cerebellum,
numerous brain stem nuclei, tracts and the IV ventricle will be visible.
94
(J1) Through Middle of Pons
Superior cerebellar peduncle
Reticular formation
mmb
mmb
Dorsal tegmental nucleus
mmb
(J2) Through Middle of Pons
Superior cerebellar peduncle
Dorsal tegmental nucleus
mmb
Reticular formation
Medial longitudinal fasciculus
Medial lemniscus
mmb
mmb
mmb
mmb
Transverse pontine fibers
mmb
Corticospinal and corticobulbar tracts
mmb
95
(J3) Through Middle of Pons
Lingula
mmb
Dorsal tegmental nucleus
Medial longitudinal fasciculus
mmb
Superior cerebellar peduncle
mmb
Corticospinal and corticobulbar tracts
mmb
mmb
Medial lemniscus
mmb
(K1) Through Rostral Medulla
Lingula
Trapezoid body fibers
Medial lemniscus
mmb
mmb
mmb
Medial longitudinal fasciculus
mmb
96
(K2) Through Rostral Medulla
Lingula
mmb
IV ventricle
Medial longitudinal fasciculus
mmb
mmb
mmb
Medial lemniscus
mmb
Trapezoid body fibers
mmb
(K3) Through Rostral Medulla
IV ventricle
Reticular formation
mmb
Vestibular nucleus
mmb
Lingula
Medial longitudinal fasciculus
mmb
mmb
mmb
97
(L) Through Glossopharyngeal Nerve
Solitary tract
Olivary nucleus
mmb
mmb
Medial longitudinal fasciculus
Inferior cerebellar peduncle
Pyramidal tract
mmb
mmb
mmb
Reticular formation
mmb
Vestibular nucleus
mmb
98
Appendix
Neuroanatomy Laboratory
Dr. Janelle LeBoutillier
Answers to Study Sheets
PAGE 11
Figure 1 – Majorgyri
1. Endomarginal gyrus
2. Marginal gyrus
3. Ectomarginal gyrus
4. A. Caudal suprasylvian gyrus
B. Rostralsuprasylvian gyrus
5. Caudal ectosylvian gyrus
6. Precoronal gyrus
What is the difference between a sulcus
and a gyrus?
On the surface of a gyrencephalic
brain, the sulci are the grooves or
“valley” and the gyri are the “hills” (see
Anatomical Terminology section)
Figure 2 – Major sulci
1. Medial longitudinal fissure
2. Endomarginal sulcus
3. Marginal sulcus
4. Ectomarginal sulcus
5. Suprasylvian sulcus
6. Ansate sulcus
7. Coronal sulcus
What is the difference between a sulcus
and a fissure?
A fissure is a very deep sulcus (see
Anatomical Terminology section)
Figure 3 – Lateral surface structures
1. Sylvian sulcus
2. Diagonal sulcus
3. Rhinal fissure
4. Pyriformlobe
5. Uncus (periamygdaloid cortex)
6. Olfactory tract
7. Presylvian gyrus
8. Presylvian sulcus
PAGE 12
Figure 1 – Ventral surface structures
1. Olfactory bulb
2. Lateral olfactory tract
3. Pyriformlobe
4. Uncus (periamygdaloid cortex)
5. Tuber cinereum
6. Infundibulum
7. Mammillary body
Which structures compose the brain
stem?
The midbrain, pons and medulla (see
Major Subdivisions of the Sheep Brain)
Figure 2 – Ventral brain stem
1. Midbrain
2. Pons
3. Trapezoid body
4. Olive
5. Pyramidal tract
6. Ventral median fissure
PAGE 13
Figure 1 – Cranial nerves
1. Olfactory bulb (I)
2. Olfactory tract
3. Optic nerve (II)
4. Optic chiasm
5. Optic tract
6. Oculomotor nerve (II)
7. Trochlear nerve (IV)
8. Trigeminal nerve (V)
9. Abducens nerve (VI)
10. Facial nerve (VII)
11. Vestibulocochlear nerve (VIII)
12. Glossopharyngeal nerve (IX)
13. Vagus nerve (X)
14. Spinal accessory nerve (XI)
15. Hypoglossal nerve (XII)
What is the difference between a
nerve and a tract?
Nerves are bundles of myelinated
axons located in the peripheral
nervous system (cranial nerves are
components of the PNS). In the
central nervous system, analogous
structures are called tracts.
Figure 2 – Rostral cerebellum
1. Lingula
2. Centralis
3. Culmen
4. Simplex
5. Ansiformlobule
6. Paraflocculus
7. Flocculus
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PAGE 14
Figure 1 – Cerebellum: lateral view
1. Lingula
2. Centralis
3. Culmen
4. Simplex
5. Tuber vermis
6. Pyramis
7. Uvula
Figure 2 – Cerebellum: midsagittal cut
1. Lingula
2. Centralis
3. Culmen
4. Simplex
5. Tuber vermis
6. Pyramis
7. Uvula
8. Nodulus
Figure 3 – Cerebellum: caudal view
1. Uvula
2. Pyramis
3. Tuber vermis
4. Paramedian lobule
5. Paraflocculus
PAGE 15
Figure 1 – Corpus callosum
1. Splenium of the corpus callosum
2. Cingulate gyrus
3. Body of the corpus callosum
4. Fornix
5. Subcallosal gyrus
6. Genu of the corpus callosum
7. Genual gyrus
What is the function of the corpus
callosum? Why is it white?
The corpus callosum is a commissure –
a bundle of myelinated axons that
cross the midline. Myelinated fibers
appear white in colour due to the lipid
(fat) composition of myelin.
What is the difference between a
commissure and a tract?
Tracts are bundles of axons that
connect one part of the brain to
another. Projection tracts typically
extend vertically (between higher and
lower brain regions) within the same
hemisphere, whereas commissural
tracts cross from one cerebral
hemisphere to the other via “bridges”
called commissures.
Figure 2 – Midsagittal structures
1. Inferior colliculus
2. Superior colliculus
3. Pineal body
4. Posterior commissure
5. Habenula
6. Thalamus
7. Massa intermedia
8. Mammillary body
9. Hypothalamus
10. Optic chiasm"
PAGE 16
Figure 1 – Ventricular system
1. Interventricular foramen
2. Third (III) ventricle
3. Cerebral aqueduct
4. Fourth (IV) ventricle
Figure 2 – Major arteries
1. Anterior cerebral artery
2. Middle cerebral artery
3. Posterior communicating artery
4. Posterior cerebral artery
5. Basilar artery
Figure 3 – Brain stem nuclei
1. Obex
2. Gracile nuclei
3. Cuneate nuclei
4. Vestibular nuclei
5. Vagal nuclei
6. Fourth (IV) ventricle
PAGE 17
Figure 1 – Dorsal view of hippocampal
formation
1. Genu of corpus callosum
2. Caudate nucleus
3. Septum pellucidum
4. Septal nucleus
5. Dorsal fornix
6. Fimbria
Figure 2 – Diencephalon + ventral view of
hippocampal formation
1. Hippocampal fissure
2. Dentate gyrus
3. Fimbria
4. Caudate nucleus
5. Stria medullaris
6. Habenula
7. Medial geniculate body
8. Pulvinar
9. Lateral geniculate body
101
Figure 3 – Lateral view of
diencephalon
1. Pulvinar
2. Medial geniculate body
3. Lateral geniculate body
4. Optic tract
5. Mammillary body
6. Optic chiasm
PAGE 18
Figure 1 – Horizontal Cut A2
1. Subcallosal fasciculus
2. Anterior thalamic nuclei
3. Medial thalamic nuclei
4. Pulvinar
5. Lateral geniculate body
6. Dentate gyrus
7. Superior colliculus
Figure 2 – Horizontal Cut B2
1. Dentate gyrus
2. Fimbria
3. Amygdala
4. Globus pallidus
5. Fornix
6. Habenulo-interpeduncular tract
7. Central gray
PAGE 19
Figure 1 – Coronal Cut C
1. Corona radiata
2. Cingulum
3. Subcallosal fasciculus
4. Caudate nucleus
5. Internal capsule
6. Putamen
7. External capsule
8. Septohypothalamic and
septotubercular tracts
Figure 2 – Coronal Cut D
1. Internal capsule
2. External capsule
3. Extreme capsule
4. Body of corpus callosum
5. Lateral ventricle
6. Septum pellucidum
7. Septohypothalamic and
septotubercular tracts
8. Anterior commissure
9. Olfactory tubercle
10. Lateral olfactory tract
Figure 3 – Coronal Cut E
1. Body of corpus callosum
2. Septum pellucidum
3. Septal nucleus
4. Column of fornix
5. Preoptic area
6. Optic chiasm
7. Globus pallidus
8. Claustrum
PAGE 20
Figure 1 – Coronal Cut F
1. Body of the corpus callosum
2. Fimbria
3. Anterior thalamic nuclei
4. Caudate nucleus
5. Amygdala
6. Fornix
7. Hypothalamus
8. Optic chiasm
Figure 2 – Coronal Cut G
1. Third (III) ventricle
2. Habenula
3. Medial thalamic nucleus
4. Ventral thalamic nucleus
5. Optic tract
6. Mammillothalamic tract
7. Fornix
8. Mammillary body
9. Dentate gyrus
10. Alveus
Figure 3 – Coronal Cut H
1. Pineal body
2. Posterior commissure
3. Pulvinar
4. Midbrain reticular formation
5. Substantia nigra
6. Crus cerebri
7. Medial geniculate body
8. Lateral geniculate body
9. Dentate gyrus
10. Alveus
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PAGE 22
Figure 1 – Coronal Cut J
1. Lingula
2. Dorsal tegmental nucleus
3. Medial longitudinal fasciculus
4. Medial lemniscus
5. Transverse pontine fibers
6. Corticospinal and corticobulbar tracts
7. Reticular formation
8. Superior cerebellar peduncle
Figure 2 – Coronal Cut K
1. Vestibular nucleus
2. Medial longitudinal fasciculus
3. Medial lemniscus
4. Trapezoid body fibers
5. Reticular formation
Figure 3 – Coronal Cut L
1. Inferior cerebellar peduncles
2. Vestibular nucleus
3. Solitary tract
4. Medial longitudinal fasciculus
5. Olivary nucleus
6. Reticular formation
7. Pyramidal tract
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