General nervous
system anatomy
Session 2
What do you think?
Objectives
• Recognize the surface of the brain from every perspective
• Correctly use the terms for the anatomical breakdown of the central
nervous system
• Compare and contrast white and gray matter and recognize terms that
distinguish them
•
•
•
•
•
•
Describe the structure of the spinal cord
Recognize cross-sections of the brain in each plane
Describe the locations and functions of supporting systems of the CNS
Describe the difference between a tract and a pathway
Visualize a second order sensory neuron
Discuss the role of major neurotransmitters
Who originally proposed the Cell Theory in
1839?
Paul Broca
Theodor Schwann
Charles Darwin
Th
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Rene Descartes
Pa
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A.
B.
C.
D.
25% 25% 25% 25%
:30
Alzheimer’s and Parkinson’s are both
characterized by progressive
degeneration of specific neurons in the
peripheral nervous system.
50%
50%
se
Fa
l
Tr
Answer Now
ue
A. True
B. False
:30
Developmental vs anatomical
breakdown
Rostral
• Development based terms
(left)
Cerebrum
• Visible structure based
terms (right and middle)
Midbrain
• Cellular level based terms
(for later on)
• Nuclei, internal structures,
Pons
Medulla
etc.
Caudal
White matter vs gray matter
• White:
• Tract, capsule, commissure, lemniscus,
fasciculus, column, peduncle, funiculus,
crus
• Gray:
• Ganglia, nuclei, cortex, specialized names
(like thalamus)
Spinal region
• Gray matter
• Horns (anatomical)
• Laminae (functional)
• White matter
• Funiculi (anatomical)
• Tracts, columns, lemnisci,
etc. (functional)
• Surface Features
• Fissures, Meninges,
Arteries
lemnisci contain synapses
Tr
Answer Now
se
ue
A. True
B. False
50%
Fa
l
50%
:30
brainstem
cerebellum
• Crus = Peduncle
• Lined with gray
matter just like
cerebral cortex
• Word cerebellum
is a diminutive of
cerebrum (minibrain)
Cerebellum – arbor vitae
Subcortical structures
• Diencephalon
• Basal Ganglia
• Lenticular Nuclei
• Corpus Striatum
• Parts of Limbic System
Cerebral cortex
• https://www.youtube.com/watch?v=6M0XbFa6Qn
Y
• Watch a zebrafish think! (kind of)
Where is the tectum located?
Midbrain
25%
25%
25%
Pons
Medulla
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id
br
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Diencephalon
M
A.
B.
C.
D.
25%
:30
Cerebral cortex
• Gray matter cortex –
gyri and sulci to increase
area
• Increased cortex area =
increased processing
space*
• White matter – connects
cortex with other
processing structures
• Increased white matter =
increased processing
power or speed*
*Professor Burnell’s unresearched hypotheses
Cerebral cortex microscope slide (stained)
Cerebrum vs cerebellum
• Brain vs. mini-brain
• Gray cortex, white tracts, deep nuclei
• Arbor vitae = capsules and commissures
• Peduncles
• Cerebellum function:
• Coordination, balance, subconscious
motor control, unknown
• Cerebrum function:
• Sensation, conscious motor control,
language, planning, etc., mostly known
identify the surfaces
Which views allow you to see the 4th ventricle?
20% 20% 20% 20% 20%
A. Anterior view of brainstem
B. Posterior view of brainstem
with cerebellum removed
C. Posterior view of brainstem
Answer Now
in
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D. Midsagittal section
E. Lateral view of brainstem
io
n
with cerebellum intact
:30
Cross sections
• Sagittal (midsagittal)
• Coronal/Frontal
• Horizontal/Transverse/Axial
Cross Sections - midsagittal
• Cerebral
cortex,
diencephalon,
brainstem
Cross sections - coronal
• Cerebral cortex and
subcortical structures
Cross sections - axial
• Cerebral cortex,
subcortical structures,
brainstem, cerebellum,
spinal cord
The lateral ventricles appear in two places (4
total) in which cross section?
Answer Now
sa
git
ta
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l
33%
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on
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A. Coronal
B. Axial
C. Midsagittal
33%
Ax
ia
33%
:30
What term best describes these structures?
sy
st
em
33%
L im
bi
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ga
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sa
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Ba
Le
nt
ifo
rm
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i
A. Lentiform nuclei
B. Basal ganglia
C. Limbic system
33%
gli
a
33%
Answer Now
:30
What is the name of this structure?
Tectum
Basis Pontis
Mammillary body
Crus Cerebri
ri
Cr
u
sC
er
eb
od
y
ar
yb
ill
am
m
M
Ba
sis
ct
um
Po
nt
is
25% 25% 25% 25%
Te
A.
B.
C.
D.
Answer Now
:30
Support Systems
• Arteries
• Vertebral -> Basilar -> Circle of Willis
• Internal Carotid -> Circle of Willis
• Veins, Sinuses
• Superior Sagittal Sinus
• CSF – Ventricles, aqueducts, canals
• Lateral ventricles -> (interventricular
foramen) -> 3rd ventricle -> (cerebral
aqueduct) -> 4th ventricle -> SAS
• Meninges
• Pia, SAS, Arachnoid, SDS, Dura
After flowing through the lateral ventricles,
where does the CSF travel next?
20% 20% 20% 20% 20%
4th ventricle
3rd ventricle
SAS
Cerebral aqueduct
Answer Now
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Interventricular foramen
4t
h
A.
B.
C.
D.
E.
:30
Tracts vs pathways
• Pathway is the whole road
trip, including stops
• Tract is one road
• Decussations
Sensory vs motor pathways
• Sensory pathways tend to have 3 neurons (primary,
secondary, tertiary)
• Motor pathways tend to have 2 neurons (upper and
lower)
First, Second, Third Order Sensory
Neurons
• 1st (primary)
• 2nd (secondary)
• Tract
• 3rd (tertiary)
• Soma in thalamus
• Ends in cortex
Upper vs Lower Motor
Neurons
• Upper Motor Neurons
• Soma in Cortex
• Synapses in spinal cord, after
decussating
• Interneurons – processing
• Lower Motor Neurons
• Starts in spinal cord, exits through
anterior root
Lower Motor neurons cross midline.
50%
se
ue
Tr
Answer Now
50%
Fa
l
A. True
B. False
:30
Neurotransmitters
• Glutamate (+)
• GABA (-)
• Dopamine – reward system, mostly noticed when absent (parkinson’s,
schizophrenia, ADHD, restless leg syndrome)
•
•
•
•
•
•
•
Serotonin – enteric NS, mood, sleep, learning, memory, etc.
CCK (cholecystokinin) – enteric NS
Acetylcholine – PNS
Epinephrine
Norepinephrine
Substance P – pain perception
Enkephalin – pain regulation
Objectives
• Recognize the surface of the brain from every perspective
• Correctly use the terms for the anatomical breakdown of the central
nervous system
• Compare and contrast white and gray matter and recognize terms that
distinguish them
•
•
•
•
•
•
Describe the structure of the spinal cord
Recognize cross-sections of the brain in each plane
Describe the locations and functions of supporting systems of the CNS
Describe the difference between a tract and a pathway
Visualize a second order sensory neuron
Discuss the role of major neurotransmitters
conclusion
• Questions on general anatomy?
• Study Guide will be posted this afternoon
• Read for next class:
• Bear Ch. 7
• L-E Ch. 5
• Pdf attachment of Haines Ch. 8