Purves et al. part of Chapter 1, Appendix, the Sylvius CD, Box A in Chapter
19 for prions, Figure from chapter 22
Here is a site I found on mouse brain
I found these pictures of stereotaxic
apparatus at the Kopf Instrument site.
Sutures in bones are landmarks for surgery, Bregma is the anterior square
one, and Lambda is the posterior V shaped one, and here
is a picture from a site where you can buy a rat skull on a chain.
Using these landmarks, a rat brain atlas, and a drill, electrodes can be
placed into specified locations for stimulating or lesioning.
Here is a site
for sheep brain dissection.
In 1970-1971, I was assigned to be a teaching assistant (TA) in Physiological
Psychology at the University of Wiscconsin - Madison for Prof. Richard Keesey.
Without the help of the senior TA, Norm Ferguson, I do not know how I would
have survived. A few years later, Norm published "Neuropsychology Laboratory
Manual" (Norman B. L. Ferguson, San Francisco, Albion Publishing Company,
1977), with good coverage on anatomy. The slide
collection I present to you is mostly the slide collection I was given to
use as a TA. For the first time in recent years, a student dissection of
the sheep brain is being incorporated into this course. The dissection
guide, which we will follow, and the glossary
of neuroanatomical terms, which is entertaining and informative, is from
the course I TAed. This lab was prepared and added to the Neuro curriculum
for Spring 2005 mostly from the efforts of Christine Zelle, Lab coordinator
for upper division biology labs. 2006 revisions included (1) labeling the
slides, (2) simplifying the dissection guide from its original version,
and (3) hyperlinking to slides from the guide; some of these revisions were
suggested by 2005 students in their course assessment.
The Prion Lecture
Chapter 19 Box A p. 427
Prion diseases - this is in the cerebellum chapter because cerebellar ataxia
is one of the characteristics of the diseases; I put it here as a warning
for obvious reasons.
Creutzfeldt - Jakob Disease (CJD) "Spongiform" (brain turns to
There were seemingly esoteric* cases of spongiform encephalitis.
* for instance afflicting Jews in Lybia who thought raw sheep eyeballs were
Kuru was a disease in New Guinea among cannibals.
D. Carleton Gadjusek (1976 Nobel
Prize) thought it was a slow virus.
Scrapie in sheep so named because they roll around with intense itching.
Personal reflection. Since we did a sheep brain dissection in physiological
psychology lab at Hopkins, I wondered if rubber gloves were necessary. Since
Baltimore was close to Bethesda, I called. Gadjusek was away, studying some
remote tribe, but I spoke with his coworker (Gibbs) who thought formaldehyde
might not kill the virus. Then I got on their mailing list and, once a month
or so, got an inch thich envelope full of case studies of diseases in far
away places. I had to move to Missouri (in 1979) to make it stop.
Stanley Pruisinger 1980's proposes "prion" (protenaceous infectious
That a disease could be transmitted without virus or bactera was heresy
at the time.
But he had strong evidence and won the 1997 Nobel
Normal protein (PrP-C [control]) is altered by altered form (PrP-Sc [scrapie])
In the 1990s when the term "mad cow disease," was applied to observations
in Britain, it seemed like a joke.
Now "BSE" (bovine spongiform encephalitis) is no laughing matter.
In meat industry, having matter from other animals in the feed is really
Can disease spread from animal to animal? (probably)
Can disease spread from animal to human? (probably)
Cases in Canida, mainland Europe, and even in the US are in the news.
Should "downers" ("cows" that have dropped to the ground)
be slaughtered for food?
How is it that meat from one downer can be sold in many different states
and, only later, the announcement is made that it had BSE?
To supplement the above material, please view the 2006
graduate student presentation on prions.
big area of cerebral cortex (2.2 square meters) from folding into sulci
Fig. 1.6 EtoH p. 11
cellular cytoarchitecture - 2 mm thick cerebral cortex
6 layers, top (I) = molecular (without cells)
Brodman made areas (from cytoarchitecture), famous:
Fig. A1 [A,B] (Appendix) p. 718
Review (already covered in first lecture) and terminology:
Rostral - caudal
Medial - lateral
Ipsilateral - contralateral
Sagittal - coronal - horizontal
gray matter, cortex, nucleus and ganglion
substantia (ex. substantia nigra) like nucleus but less distinct
locus (l. coeruleus) small distinct group
nerve, white matter, tract
bundle (medial forebrain bundle) go together but unrelated
capsule (internal c.) cerebrum - brainstem connection
commisure - one side to another
lemniscus (medial l.) - like ribbon
Fig. A10A p. 728
Fig (more detail) from Atlas, p. 746
Overall external anatomy viewed laterally
Shows brains of mammals (cortex = "bark")
cerebrum senses - hemisphere controls contralateral
cerebellum (little brain) - hemisphere controls ipsilateral
Central Sulcus divides
postcentral gyrus (primary sensory projection)
precentral gyrus (primary motor area) Brodman made area 4 motor
Lateral (Sylvian) fissure
Fig. A3 p. 720
frontal lobe - planning behavior
parietal lobe - attending to stimuli
temporal lobe - recognition
occipital lobe - visual analysis
Figure, (not in book anymore, but relates to Fig. 22.3 p. 482)
Developmental introduction to neuroanatomy
(there is also a development chapter, chapter 21)
Each of the above develops further. note (especially):
Telencephalon -olfactory bulbs, cerebral cortex, basal ganglia, hippocampus,
Diencephalon is thalamus (sensory & motor "relay") and hypothalamus
Mesencephalon - tectum -> superior and inferior colliculi (vision and
Metencephalon - cerebellum, pons
Myelencephalon - medulla - auditory, somatic, gustatory
Table A2 (appendix) pp. 724-725
Fig. A7 (appendix) p. 723
Fig. More detail from atlas p. 747
from sheep brain dissection
ventral view of brain
cranial nerves.(some are tracts)
sensory vs. motor, somatic vs. visceral (autonomic)
III occulomotor - goes to 4 external eye muscles, pupil, accomodation, eyelids
IV trochlear - to superior oblique muscle
V trigeminal - somatic from face, chewing
VI abducens - to external rectus muscle of eye
VII facial - facial muscles, lacrimal and salivary glands, taste
VIII auditory / vestibular
IX glossopharyngeal - taste from back of tongue, sense from pharynx, carotid
X vagus - autonomic, sensation, vocal cords, swallowing
XI accessory - shoulder & neck muscles
XII hypoglossal - tongue movements
some other ventral landmarks:
pyramids- of pyramidal (corticospinal tract) (decussation is caudal to this)
mammallary body, pons, inferior olive (motor control), rhinal fissure, etc
optic nerve, chiasm and tract
cerebral peduncles - axons between brainstem and cortex
Fig. A14 p. 734
Fig (Magnetic resonance) from atlas, p. 748
neocortex (found only in mammals),
hippocampus (archipallium) (one cell layer) (seahorse shaped)
and olfactory cortex
Fig A12 p 730
Fig, more detail, from atlas, p. 746
thalamus, hypothalamus, midbrain, pons, medulla
(subthalamus is between, concerned with motor function)
corpus callosum, anterior commisure, cingulate sulcus and gyrus, etc.
optic chiasm, infundibular stalk, pituitary, mammallary body, pineal, colliculi,
some of these are in limbic system (chapter 29)
Fig. A8 p. 724
dorsal view of midbrain and brainstem
Cerebellum has 3 peduncles
superior and inferior colliculi
many important nuclei, principally of cranial nerves, are drawn in
Fig. A14A p. 734
this view is especially good for the basal ganglia and internal capsule
striatum = caudate + putamen
Fig Magnetic resonance p 752
Prep for dissection
Fig. A2A p. 719
spinal cord - cervical thoracic lumbar and sacral nerves
Cauda equina branches out toward bottom
meninges (as in meningitis)
(1) dura (2) arachnoid (3) pia
subarachnoid space has cerebrospinal fluid (CSF)
So do ventricles.
the CSF is "isolated" by the blood-brain-barrier (BBB)
and is secreted by the choroid plexus
Exam questions from 2005 - 2012 relating to this outline (plus dissection
guide and slides)
With your "orange stick," you scrape all the gray matter out
of one sulcus. Answer either (1) How can you tell what direction the myelinated
axons run? or (2) Where do the first axons you find come from and go to?
stick glides in axon direction and scrapes across the grain, from and to
the adjacent gyri
In the corticospinal tract, these motor cells in the precentral gyrus make
their first synapse (where?).
to the spinal motor neuron in the ventral horn
You have a rat brain atlas and your anesthetized rat (in an approved protocol)
is mounted in a stereotactic device with the skull exposed. Say something
about what you need to do to get the tip of an electrode into the ventromedial
nucleus of the hypothalamus.
measure from the bone sutures*, drill a hole, lower the electrode to the
correct depth*, *=requires consulting the atlas
Before Pruissinger's prion hypothesis... answer either (1) What kind of
disease? was explained by Nobelist Gadjusec by a virus? (2) A virus with
what special kind of properties?
spongiform encephalitis, CJD, kuru, etc.; slow
The medial forebrain bundle goes through the lateral hypothalamus and includes
[answer either] (what famous tract?) that is disupted in (what disease?).
nigrostriatal tract, Parkinson's
What do you have to cut off to see the floor of the fourth ventricle?
The left side of the cerebellum controls which side of the body?
"Massa intermedia" is an operational term for what major relay
structure in the brain?
If you miss the midsagittal cut a tiny bit... Name one of the three tracts
you would see where the thalamus is located.
fornix, mamillothalamic tract, habenulopeduncular tract
For questions 10-13, see this
10. Name this structure (or give it's cranial nerve number)
olfactory bulb, I
11. This white matter is seen in the midsaggital view as... (name either
of the two tracts).
fornix, hippocampal comisure
12. What is this artery that feeds the circle of Willis?
13. What is this structure?
lateral geniculate nucleus (thalamus)
For questions 14-21, see this
14. These fibers, hidden as they pass under the pons, form what tract?
15. Here it is called the pons. What do you call these fibers, on the "other
side," in the dissection of the 3 components of the cerebellar peduncle?
brachium pontis or middle cerebellar peduncle
16. This one nucleus is in a system with two others. Name one of the two
putamen, globis pallidus
17. What is the frog's equivalent of this structure?
18. What is this major body of white matter called?
19. What was revealed after you removed this important limbic structure
wrapped in myelinated axons (i.e. under the structure you removed)?
20. The brains provided for your dissection still had this white "membrane"
(called what?) that you were required to remove before proceeding.
21. For this figure, answer either (1) What is it called when the entire
white matter under the cortical layers is exposed? or (2) What is the term
used for these particular axons?
corona radiata, arcuate fibers
How did Pruisinger propose that a protein (without DNA or RNA) can be infectious
and alter the proteins in the victim, making those proteins infectious.
protein in scrapie configuration converts protein in control configuration
into the scrapie form
Other than cerebral cortex, name a major component of the telencephalon.
basal ganglia, hippocampus, olfactory bulb, basal forebrain
The oculomotor nerve (cranial nerve #3) has strictly motor function. State
one of the other motor functions (other than connections to striated muscle
associated with the eye).
accomodation, pupillary reflex
For striatum or lenticular nucleus, explain how the body got its name.
striated because of branches of internal capsule, shaped like a convex lens
in horizontal section
(for # 15-19) go here
15. Give a name, number or function of the cranial nerve indicated.
occulomotor, 3, eye movement, pupil, accomodation
16. Give the function (for both) or a name (for either) area of white matter
outgoing voluntary motor tract, trapezoid body, trapezoid body
17. What is this white area called?
18. Answer either (1) What is this structure called? Or (2) Say one of the
things you would see if you removed that structure.
septum pellucidum, head of the caudate and lateral ventrical
19. What is this area called?
hypothalamus, third ventrical
(#s 20-24) go here
20. What is this white matter called?
21. What is this large structure in the middle of the brain called?
22. What is this white matter called?
23. What is the white matter on the outside of this structure called? (Alternatively,
you could say one of the tracts on the midsagittal slice you see that are
formed from these axons.)
fimbria, fornix, hippocampal commisure
24. What white matter is being ripped here?
(#s 25-29) go here
25. What kind of information is being carried by this tract?
26. What is this cross-over structure called?
27. What is this large area of the brain called?
28. You definitely saw this huge nerve in your dissection (pointed to twice).
Give a name or number. Hint: there are 3 branches coming in from touch sensation
in the the face.
29. What is the name associated with the gray matter you needed to scrape
away (from the mid-sagittal plane) to reveal this tract?
massa intermedia, thalamus
For Questions 1-8, refer to these
1. Although it is operationally named the "massa intermedia,"
it is actually (what specific part of the brain?).
2. What is this conspicuous white structure seen in mid-sagittal section?
3. From a different perspective, you peeled off the hippocampus and saw
this. Answer either (1) What is it called (specifically)? Or (2) What (functional)
system is it part of?
lateral geniculate nucleus of the thalamus, visual
4. From a different perspective, you saw this structure hiding in the lateral
ventricle behind the septum pellucidum. What is it?
head of the caudate nucleus
5. What is the name of this colossal body?
duh, corpus callosum
6. The hippocampus, shown here, is associated with white matter over its
surface plus two tracts that can be seen in (or near) mid-sagittal section.
One of those three would suffice for the answer.
fimbria, fornix, hippocampal commisure
7. A structure associated with the visual system is here. Answer either
(1) What is it called in the sheep? (2) What is it called in the frog? Or
(3) In combination with a nearby auditory structure, both bilateral, what
name indicates this foursome?
superior colliculus, optic tectum, corpora (lamina) quadrigemina
8. When you cut off the cerebellum and looked at the floor of the fourth
ventricle, what was this structure called (viewed from that perspective)?
brachium pontis of the cerebellar peduncle
Look here for 9-12
9. You can see this tract of white matter on the ventral surface of the
brain. What system is it part of?
10. Suppose I'm pointing to the diencephalons, not the ventricle. What part
of the diencephalons is this?
11. This and the nearby tracts and the associated gray matter are part of
a major subdivision of the brain collectively called (what?).
12. Which nerve controlling extraocular muscles has been cropped out?
13. Your animal care protocol is approved. You have your anesthetized rat
in the stereotaxic device and you have exposed bregma and lamda. What else
do you need to aim an electrode tip to the ventromedial nucleus of the hypothalamus?
a rat brain atlas
14. How come you do not have spongiform encephalitis even though you have
the protein in your brain, and even though you could contract spongiform
encephalitis if exposed to tissue from a person or animal that does?
the protein would need to be changed to the diseased configuration (scrapie)
from the normal configuration (control)
15. You are looking at the outside of the brain. Name a structure from the
prosencephalon that you cannot see.
basal ganglia (any of them), hippocampus, internal capsule
16. 'The cranial nerves have sensory and motor functions. Regarding motor
functions, they can be either for the (list both) motor systems."
autonomic & somatic
17. "The thalamus is a 'relay' for " Complete that sentence for
both general functions.
sensory and somatic motor
For questions 1-5, refer here
1. The dissection reveals the brachium pontis, the brachium conjunctivum
and Answer either (1) the third part. Or (2) the whole structure (all three
restiform body (inferior cerebellar peduncle), cerebellar peduncle
2. Rostral to the above, in the midbrain, is the lamina quadrigemina. Answer
either (1) the function of the inferior pair. Or (2) the function of the
auditory center, visual center
3. Answer either (1) name or number of this nerve. Or (2) a specific function
other than somatic motor control.
occulomotor (III), autonomic (pupil and accomodation)
4. What is the artery that feeds the circle of Willis?
5. Answer either (1) What is the function of the axons you see here? Or
(2) What is the name given to the structure delineated here?
(pyramidal) motor system (corticospinal tract), trapezoid body
For questions 6-11, refer here
6. If you could see through the optic chiasm, what diencephalic structure
would you be seeing?
hypothalamus (suprachiasmatic nucleus)
7. Tracts branching from what huge white matter structure give rise to this
8. "Periaqueductal gray" where the aqueduct connects what two
3rd and 4th
9. Here's a place you've heard of. (hint, the site of action of N-acetyltransferase
and hydroxy indole O-methyl transferase)
10. Looks like we missed "mid" in this midsagittal cut by a bit.
What nucleus would we see in the lateral ventricle on the other side?
11. What is this white matter?
For questions 12-15, refer here
12. What is this white matter?
internal capsule (corona radiata)
13. You had a difficult time peeling off this tough layer called (what?).
14. In addition to the fornix, what white matter from the fimbria is found
in this area?
15. If we tear through this (what is this?), we will see (answer to #10).
16. You have a rat in a stereotactic instrument. How do you decide where
to drill the hole through the skull to reach a specific location?
a stereotactic atlas tells you the location relative to (XY) bone suture
(lamda and bregma) and depth (Z)
17. With a stereotactic instrument, you aim for the medial nucleus of the
hypothalamus and make a lesion (and collect data on the animal's weight
for a few months). How can you know whether you hit your intended target?
You must do histology on the brain to see if the lesion is near the intended
target (as identified in the atlas)
18. Part of the human retina projects to the contralateral lateral geniculate
nucleus. The other part projects to the (what?) lateral geniculate nucleus.
19. You can contract Creutzfeld Jacob disease by eating contaminated tissue.
Why is the current hypothesis explaining the spread of such diseases so
contradogmatic with respect to infectious diseases?
no nucleic acids are involved, only protein, and even here, it is conformation
that is critical
20. Using a term such as "myelencephalon," where is the frog's
21. There are sensory and motor functions for the cranial nerves. In addition
to striated muscle control, what other kind of motor control do the cranial
22. "The thalamus is a major relay station" [yes, I know that
is an oversimplification] "for the motor system and for (what?)."
sensory systems as they project to the cortex
23. Why is the medial forbrain bundle called bundle instead of tract?
It is a collection of different tracts with different functions traversing
24. "When you dip your face in water, parasympathetic and sympathetic
changes mediate the diving response" caused by sensory input from what
25. "The fimbria forms the fornix" and also it makes (what big
gray area?) look white.
26. Answer one of these: (1) Why would you need to use a different method
of lesioning to study the behavioral effects of lesions of the hippocampus
(compared with, say, the ventromedial nucleus of the hypothalamus). Or (2)
how would you do such lesioning?
(1) it is huge, (2) use suction (or a lot of electrolytic lesions
27. What, specifically, takes up more space in the cervical and lumbar enlargements?
28. What is the function of the choroid plexus?
secrete cerebrospinal fluid
29. The brainstem is considered to be the midbrain, the medulla, and (what?)
30. The more conventional name for the archipallium.
For 1-16, refer to Figs 1st
p, 2nd p,
3rd p, 4th
1. The name of this bulge.
2. The name of this blood vessel feeding the circle of Willis.
internal carotid artery
3. The name of this ventricle.
4. The name of this nucleus. Its function. (two points)
caudate, motor (extrapyramidal
5. The name of this tract.
6. What big tract is being ripped here?
7. The name of this structure.
8. What part of the thalamus is this?
9. The name of this whole tract that is teased into 3 components on the
10. Name one of the two nuclei that form this lens-shaped nucleus.
ptuamen, glogus pallidus
11. The name of this bulge. The name of the equivalent structure in the
frog. (2 points)
superior colliculus, optic tectum
12. The name of this big bundle of cross over axons.
13. The name of this bulge. Its function. (2 points)
precentral gyrus, motor
14. The name of this major subdivision of the brain.
15. The name of this small bundle of cross over axons.
16. The name of this major subdivision of the brain.
Using a stereotaxic atlas of the rat brain and a stereotaxic apparatus,
what do you measure from on the rat's head to find a defined brain location
like the ventromedial nucleus of the
bone sutures bregma and lambda
Why do they call part of the basal ganglia the "striatum?"
brances off the internal capsule make these nuclei look striped
Only one of the cranial nerves for eye movements is also part of the parasympathetic
nervous system. Which?
When you remove the cerebellum, you are looking at the floor of which ventricle?
The hippocampus looks white because of axons of the fimbria that form what
Among the meninges (brain membranes), which is the toughest?
When Stanley Pruisinger, who eventually won a Nobel Prize, proposed the
prion theory for spongiform encephalitis, how was he disagreeing with the
Nobel Prize winning work
of D. Carleton Gadjusek?
SP said a protein could be infectious while DCG thought more traditionally
that it was a virus (a slow one)
For questions # 1 - 4, refer to this
1. This gray matter. Note that it is covered with white matter. Also note
its location between the white matter of the cerebral cortex and the thalamus.
2. This thin midsagittal structure blocks your view into the lateral ventricle
and the head of the caudate nucleus.
3. Part of the mesencephalon, this part of the lamina quadrigemina is a
visual area related to the optic tectum of the frog.
4. This bulge, white matter, leads to the brachium pontis of the cerebellar
pecuncle. On the ventral view of the brain, it blocks your view of the pyramidal
for 5-8, see this
5. If you started cutting into the longitudinal fissure, what is the first
white matter you would cut?
6. This visual structure blocks your view to the supraoptic nucleus of the
7, Many of the brains we had for dissection showed this ribbon-shaped cranial
oculomotor nerve (III)
8. This tract is named for its connection from the thalamus to what specific
portion of the hypothalamus, a body which would be conspicuous on the ventral
for 9-12, see this
9. This portion of the cerebellar peduncle has axons that are seen in what
10. What commisure is here? (The arrow does not point to the corpus callosum.)
11. What major subdivision of the brain is this?
12. Why is the hippocampus white?
its output axons, the fimbria, are on the surface
"Each picture in a stereotactic atlas of the rat brain is a coronal
section with its distance anterior or posterior of bregma indicated."
coronal is dorsal-ventral, lateral-contralateral plane, and bregma is a
landmark on the sutures of the bones
Why did I decide to tell the prion story in the neuroanatomy lecture before
the brain dissection?
to give you a cautious appreciation for how contact with neural tissue,
in the case of scrapie, might be dangerous
The pons covers up a white matter that goes from the cerebral peduncles
through the pyramids. What is this tract (not the pons, rather the tract
covered by the pons) used for?
The most obvious of the "membranes" (meninges) of an "un-peeled"
brain is a very thick and tough one called the (what)?
"Bundle," "capsule,""commisure," and "lemniscus"
are all terms referring to what specific type of tissue?
Toward the bottom of the spinal cord, there are many parallel tracts. What
is this called?
Sometimes caudate plus putamen is called striatum. Why?
looks striated from branches of white matter off the internal capsule
What vascular tissue, seen dark in dissection, secretes cerebrospinal fluid?
For 1-3, see here
1. In some brains, this was intact, in others, it was damaged, revealing
a fluid-filled compartment. What is it?
2. Hardly anybody had this good of a view of this pair of laterally projecting
nerves found near the stump of this obvious rostrally projecting nerve.
Give the name or number of one of them.
Facial (7) or auditory (8)
3. If this tract is followed laterally and superiorally, with the cerebellum
removed, it is part of a huge structure of white matter. What is this white
For 4-8, see here
4. Here is white matter (covered by the pons). What is the function of this
white matter tract?
motor (pyramidal [corticospinal] tract)
5. Between the two lines (and just on the other side of the optic chiasm)
lies what structure, important in motivation?
6. With the cerebellum removed, what are the midbrain structures seen
superior (and inferior) colliculi,, lamina (corpora) quadrigemina
7. and what would the visual counterpart be called in the frog?
8. What ventricle is this?
For 9-12, see here
9. What motor nucleus is right on the other side of the septum?
10. What is the name of this huge area of white matter?
11. Covered by the hippocampus, what is the specific function of this part
of the thalamus?
vilson (lateral geniculate nucleus [body])
12. The fimbria fibers that make this structure white are bundled together
in what tract that can be seen in mid-sagittal section?
What distinguishes a bundle (like the medial forebrain bundle) from a tract?
several unrelated tracts travel together
What are the diencephalic structures that would be seen in the neighborhood
of the third ventricle?
thalamus and hypothalamus
The surface of the hippocampus is white. How, during the dissection, would
you ascertain the direction that these axons go?
stroke with the grain and across the grain with the cuticle stick
Starting at the lumbar area and going through the sacral area, describe
the spinal cord.
cauda equina, a bunch of nerves
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