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Central Nervous System
Terminology
Cerebral Hemispheres
Subcortical Structures
Brain Stem
Cerebellum
Brain Systems
Protection of the Brain
Spinal Cord
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Terminology
Anatomical References
Anatomical structures can be sectioned along flat
surfaces
(planes)
Note: The
nervous system is organized along an anterior
Anatomical
structures
can
be
divided
into
a.
Coronal
(frontal)
Anatomical
structures
can
be
divided
into
sides
Relative
position
of
anatomical
structures
to
posterior
axis
with
acan
fluidbe
filled
tubeinto
running
through
Anatomical
structures
divided
top
and
bottom
Longitudinal
axis
andplane
back
Exit
Home structure
i.front
Vertical
a.
Midline
a.
Ipsilateral
the
center.
At thedividing
anterior
end, the into
structure have
a.
Superior
a.
Nervous
system
is
organized
along
an anterior
Front
anterior/posterior
parts
b.
Medial
i.i. Structures
localized
the
same side and to
enlarged
with
evolutionary
advancement
Dorsal
(Posterior
fortobipeds)
to
posterior
axis
i.Contralateral
Anterior
b.
i.Sagittal
Close
to thefor
midline
b.
accommodate
this enlargement, the brain has
b.
Inferior
b.
Different
regions
of the
brain have
different
ii.
Rostral
i.
Vertical
plane
dividing
structure
into
c.
Lateral
i.i. Structures
localized
to
different
sides
become
distorted
and
curved
so that
some structures are
Ventral
(Anterior
for
bipeds)
longitudinal
axis
b.
Back
right
and
left
halves
i.Proximal
Away
from
theassign
midline
c.
more
difficult
to
anatomical references.
i.Midsaggital
Cerebellum
is ventral to the forebrain axis but
Posterior
ii.
(median)
i. Close
to a fixed
reference point
dorsal
to that of the brain stem
ii.
Caudal
iii.
Parasagittal
d. Distal
c.i.Horizontal
Distant to(transverse)
a fixed reference point
i. Divides structure into superior and inferior
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Terminology
Nervous system terminology
Terms
Important
referring
sulci to
and
axons
gyri
Terms
to neuron
cell
bodies found
in CNS
Neural referring
cell bodies
are often
organized
in rows
a.
Grey (projection)
matter
Tract
a.
Lamina
Nerve
Terms Sylvian
that refer(lateral)
to the external
morphology of the
fissure
i.
Generic
term of
forcell
neurons
inseparated
the CNS from another
Bundle
i.brain
Rowreferring
or layer
bodies
Terms
to
neuron
cell
bodies
found in PNS
i.
Refers
to
CNS
Cingulate
sulcus
i.
Refers
to
PNS
i.Parieto-occipital
Separates
temporal
and
White
Central
matter
sulcus
b.
Nucleus
sulcus
row
or
layer
by
a
layer
of
axons
or
dendrites
a.
Surface
convolutions
a.
Ganglion
Precentral
gyrus
Calcarine
sulcus
i.
Collection
of
axons
that
run
together
Insula
i.
Clearly
defined
mass
of
neuron
cell
bodies
i.
Medial
surface
of
the
frontal
frontal
lobes
ii.
Parallel
structural
surface
i.to
Extends
from
superior
toof
Commissure
ii.
Set
of
axons,
also
known
as
fibers,
i. Separates
frontal
(anterior)
i.Collection
Gyrus:
ridge
on
the
surface
of
the
cerebrum
(and
of
neurons
in
the
PNS
ii.
Bundle
of
axons
either
projecting
i.
Generic
term
for
a
collection
axons
i.
Medial
surface
of
the
i.Substantia
Commonly
known
the
motor
cortex
c.
i.not
Fold
created
byas
the
temporal
but
do
necessarily
share
the
same
and
parietal
lobes
b.cerebellum)
Column
ii.
Temporal
is
inferior
to
the
inferior
surface
i.from
Any
collection
of
axons
that
connect
that
project
from
one
structure
andor
and
parietal
lobes
(posterior)
the
CNS
to
a
muscle
or
gland
i.
Less
distinct
borders
than
nuclei
occipital
lobe
i.origin
Row
oflobe
cells
perpendicular
the
surface
of the brain
ii.
Inferior
to
thistoto
sulcus
is the
or
destination
ii.
Sulcus:
groove
frontal
and
extends
the
ii.
Divides
parietal
from
one
side
of
the organ
brain
with
the
other
side
form
synapses
on
a
second
common
d.
Locus
a
ii.
sense
Defines
the
location
to
the
CNS
of
the
ii.from
Share
a
common
function
ii.
Commonly
referred
to
as
the
iii. Fissure:
a deep
grooveoccipital lobe
limbic
lobe
caudally
located
occipital
lobes
i. structure
Small but
well defined
visual
cortex mass of neuron cell bodies
operculum
iii. Parietal lobe is superior to
lateral fissure
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Terminology
Organization of the nervous system
Organization of gray and white matter
a.Functionally
CNS
organized into two divisions
i. Gray
matter
is organized
on the
surface of
a.
Central
nervous
system
(CNS)
thei. brain
lamina
Brainin(Cerebellum,
cerebrum and
ii. White matter is organized centrally
brain
stem)
iii. White matter constitutes the majority of
ii.
Spinal
cord
brain mass
Peripheral nervous system (PNS)
b.b.PNS
Somatic
i.i.Gray
matter is centrally located
ii.ii.White
matter is organized on the surface
Autonomic
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Cerebral Hemispheres
General characteristics
Lobes
Organized into functional areas
a. Motor
Contralateral
control
the body
i.Functions
Voluntaryare
control
ofofmovement
lateralized
Function
arises
from is
concerted
activity
a.a.Sensory
Each
concerned
b.
Eachhemisphere
hemisphere
has
unique
with
the opposite
of the body
i.functions
Conscious
awareness
of sensation
c. Association
i. Integration
ii. Emergent properties
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Cerebral Hemispheres
Motor areas
Primary motor cortex (Brodmann 4)
Cortical
involved
in movement
a. Located
in the areas
precentral
gyrus of frontal
lobe
b. Conscious
control
of cortex
motor
execution
a.
Primary
motor
cortex
Broca’s
Premotor
area (Brodmann
(Brodmann
44/45)
6)
Frontal
eye
field
8)throat and
c. Pyramidal
cells
give
rise
to
corticospinal
tracts
a.
a. muscles
Learned
motor
of(Brodmann
thethe
tongue,
skills
lips
b.Directs
Premotor
cortex
a. Voluntary
movement
of related
the eyes
d. Somatotopy
b.
Motor
planning
i.
Patterned
for
or
speech
repetitious
activity
c.
Broca’s
area
i. Body is mapped (motor homunculus)
ii. Representation
is proportionate
to level of motor control
d. Frontal eye
field
iii. Innervation is primarily contralateral
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Cerebral Hemispheres
Sensory areas
Cortical areas involved in processing sensation
Visual
Auditory
areas
Body isareas
mapped
Primary
somatosensory cortex (Brodmann 1, 2 & 3)
(somatosensory
a. homunculus)
Parietal lobe
a. Primary
visual cortex
(Brodmann
17) 18
b.
Visual
association
areas
(Brodmann
i. Postcentral
gyrus
a.i.Primary
auditory
cortices
(Brodmann
Somatosensory
association
area
(Brodmann
5 & 7)
Occipital
lobe
&
19)
Gustatory
cortex
(Brodmann
43)
b. Auditory
association area (Brodmann
42 & 43)
Olfactory
cortex
Representation
is
b. Somatici.ii.41)
senses
Located
primarily
insensory
calcarine
Interpretation
of visual
stimuli
a.
Parietal
lobe
deep
to
the
temporal
lobe
Recognition
of
stimuli
as
specific
auditory
a. proportionate
Integrate
various
somatic
inputs
a. i.Medial
aspects
of
temporal
lobe
i.ii.Superior
margin
of temporal lobe
i. Pain experiences
and
temperature
sulcus
Past
visual
experiences
(e.g.,
speech)
i. Piriform
lobe
(uncus)
to number
of
sensory
ii.
Pitch,
rhythm
and loudness
ii.receptors
Touch iii.
and
proprioception
Sensory
function
with largest cortical
representation
c. Somatotopy
Innervation is primarily contralateral
Innervation iv.
is primarily
contralateral
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Cerebral Hemispheres
Association areas
Language areas
a. Bilaterally located
b. Wernicke’s area
Association
areas
(in
addition
to
i. Posterior
temporal
lobe on11
left
side
General
Prefrontal
interpretation
cortex
(Brodmann
area
&these
47) discussed before)
Characteristics
a.
cortex
Sounding
out
unfamiliar
words
a.Encompasses
a.ii.Prefrontal
Anterior
portion
parts
of
of frontal
temporal,
lobe
parietal and occipital lobes
a. Analyze,
recognize
andbehavior
act on sensory
in puts
Gnostic
area
i. b.
Generally
b.
Intelligence,
found
complex
on
the
left
learned
side
and
personality
c. Affective language areas
b.
Multiple
inputs
and
outputs
b. Storage
c.i.Language
Understanding
of complex
written
sensory
and
memories
spokeand
language
c.
areas
Located
contralateral
to
Broca’s
Wernicke’s areas
ii. Nonverbal and emotional components of language
ii. Sounding out unfamiliar words
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Cerebral Hemispheres
Organization of the cortex
Neocortical layers
a. Layer I
i. Few
cells; primarily
axons, dendrites and synapses
Common
features
b. Layers II & III
a. Cell bodies
are arranged in sheets (layers)
Cytoarchitecture
i. Pyramidal
cells that project to and receive projections
i.Lamina
Parallel
surface of brain
froma.other
corticaltoregions
b.
Layer
I of
lacks
bodies
c. Layer
IV
i. Layers
cellscell
parallel
to brain surface
i. Stellate
cells that layer
receive most of thalamic input and
Molecular
b. i.Columns
project
locally
to one
otherlayer
lamina
c.
At
least
has pyramidal
cells
i.
Row
of
cells
perpendicular
to
brain
surface
d. Layer
V
&
VI
i. Share
Emit large
apical function
dendrites
ii.
a
common
i. Pyramidal neurons that project to subcortical regions
ii. Extend up to layer I
such as the thalamus, brainstem, and spinal cord, and other
cortical areas
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Subcortical structures
Basal nuclei (ganglia)
Structures
Function
Organization a. Caudate
a. Motor control
a. Receive inputs from most cortical structures
i. Starting, stopping
and monitoring movement
b.
Putamen
b. Project to motor cortex via the thalamus
ii. Inhibit unnecessary
movement
c. Globus
pallidus
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Subcortical structures
Diencephalon
Thalamus
Hypothalamus
Epithalamus
Organization
c.
control
center nuclei
of the body
a. Visceral
Comprised
of multiple
a.i.Core
ofnucleus
forebrain
Autonomic
control
(e.g.,specific
BP, HR)
Each
receives
a. Pineal
body
i.
Surrounded
by
cerebral
hemispheres
a.
Location
ii.
Emotional
response (fear, sex drive)
afferent
projections
i.
Control
of
sleep-cycle
b.
Three
bilateral
structures
b.i.
Connected
Between
optic
to
the
chiasm
pituitary
and
iii.
Regulation
of
body
temperature
ii.
Nuclei
interconnect
ii.i.Melatonin
Thalamus
mammillary
i.
Via
infundibulum
bodies
iv.
Regulation
of feeding
iii.
Nuclei
project
(relay) processed
b. ii.
Choroid
plexus
Hypothalamus
ii.
Below thalamus
v.
Regulation
of
thirst spinal
information
to
particular
cortical
areas
i.iii.
Production
of
cerebral
fluid
(CSF)
Epithalamus
Regulation
of circadian
rhythm
b.vi.
Process
and relay
information
vii. Control of endocrine function
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Brain Stem
Structures
1. Lies between pons and spinal cord
Midbrain
Pons
Medulla
oblongata
1.4.Lies
between
midbrain
andfunction
medulla
Control
of
visceral
motor
a.a.Cerebral
No obvious
peduncles
demarcation between
2.a.Comprised
mostly
of conducting fibers
Cardiovascular
center
medulla
i. Fiber tracts
and spinal
connecting
cord cerebrum with
a. i.Connection
between higher brain areas
Cardiac
center
inferior
2. Landmarks
structures
and
spinal cord center
ii.
Vasomotor
b.
a.Corpora
Pyramids
quadrigemina
i. Longitudinal
projections
Organization
Functions
b.
Respiratory
center
i.i.Superior
Descending
and corticospinal
inferior colliculi
tracts
b. i.Pontine
nuclei
Functional
1.
Autonomic
areas
behavior
Control
rate
and
depth
of breathing
c. ii.
Substantia
Decussate
nigra
i. Relay
information
between
a.
2.
Midbrain
Pathway for
fiber motor
c.
Reflex
3.
i. Color
Nucleiisfor
due
several
to melanin
cranial
(DA
nerves
precursor)
cortex
and
b. cerebellum
tracts
Pons
i.
Vomit
a.
ii. Hypoglossal
Nucleus of DA
(XII)
neurons
3. ii.
Nuclei
forMedulla
severalnerves
cranial nerves
c.
3.
Cranial
oblongata
Hiccup
d.
b.Red
Glossopharyngeal
nucleus
(IX)
a. iii.
Trigeminal
(V)
Swallowing
c.
i. Motor
Vagusreflex
(X)
b. iv.
Abducens
(VI)
Coughing
e.d.Reticular
Accessory
formation
(XI)
c. v.
Facial
(VII)
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Sneezing
e.
i. Some
Vestibulocochlear
of
the
RF
nuclei
(VIII)
are
found
here
BASIM ZWAIN LECTURE NOTES
Cerebellum
Function
Anatomy
2. Structure
a. Bilateral
b. Consists of cerebellar hemispheres
i. Connected by vermis
1. Location
c. Hemispheres
consists of lobes
i. Posterior
Dorsal
to ponscontraction
and medulla
Precisea.timing
of skeletal
ii. Anterior
b. Caudal
to occipital
lobe
a. Sensory
and motor
information
is integrated
iii. Flocolonodular
d. Gray and white matter is organized like cerebrum
i. Gray outside/white inside
e. Cerebellum is connected via cerebellar peduncles
i. Fiber tracts connecting brain stem and sensory
cortices
with cerebellum
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Brain Systems
2. Structures
Reticular
Limbic
system
formation
a. Upper part of brainstem
b. Complex
Rhinencephalon
1.
of nuclei and white matter
Septal nuclei
a.i.Disperse
and widespread connectivity
Cingulate gyrus
2.ii.Location
Group
of
cortical
structures
iii.
Parahippocampal
gyruspons and midbrain
a.1.
Central
core
of medulla,
Located
on medial aspect of the cerebral
iv.Function
Hippocampus
3.a.
3. Function
and diencephalon
c.hemisphere
Amygdala
a.
Maintain
wakefulness
attention
a. Emotional and and
affective
state
Connectivity is
complex
d.b.
structures
i. Diencephalon
Coordination
of
all afferent sensory
i. Hypothalamus
information
Anterior nucleus
of the activity
thalamus
b.ii.Coordination
of muscle
e.i.Fiber
tracts of efferent motor information
Modulation
i. Fornix
ii. Fimbria
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Protection of the Brain
Blood-brain
Primary
Meninges
Cerebrospinal
mechanism
barrier
fluid (CSF)
Brain environment
is tightly
controlled
Anatomy
of the ventricular
system
a. Most bloodborne substances cannot readily
3.
Arachnoid
enter
the
brain
2.1.
Dura
Bone
Function
e.
Dural
septa
a.
Four
fluid-filled
chambers
a.
Loose
cover
over
brain
d.
Third
is connected
with
fourth
Mechanism
a.
Two
fused
layers
a.
Brain
is
encased
in
a
bony
skullcap
Flow
a.
Form
a
liquid
cushion
for
i.Does
Falx
i.
Paired
cerebri
lateral
d.i.Arachnoid
villi
not
enter
sulci
1. via
Structure
cerebral
aqueduct
a.
Capillary
endothelium
is
joined
by
tight
i.2.
Periosteal
layer
Membranes
a.
Produced
in
ventricles
CNS
organs
ii.
Falx
ii.
Third
cerebelli
i. Small
Act
like
valves
b.
space
between
dura
and
arachnoid
a.
Three
connective
tissue
membranes
Choroid
plexuses
4.
Pia
e.
Fourth
is
continuous
with
junctions
ii.
Meningeal
layer
a.
Meninges
Found
in
ventricles
and
b.
Provides
nutrients
iii.
Tentorium
iii.
Fourth
ii.
Projection
of
archoid
through
dura into
b.
Exit
4th
ventricle
i.i. Subdural
space
i.
Dura
mater
(tough
mother)
central
a. Clings
canal
tightly
to brain
a.
Produce
CSF
Relatively
impermeable
b.
Periosteal
layer
is
attached
to the
skull
3.
Fluid
c.
CSF
composition
is
f.
Dural
sinuses
b.
Chambers
are
continuous
with
dural
sinuses
central
canal
of
spinal
cord
c.
Bath
brain
c.
Subarchnoid
space
ii.
Arachnoid
mater
(spider
mother) layer
f.
b.
Fourth
Invested
has
with
openings
blood
to
vessels
b.
Located
in
ventricles
Barrier
is
selective
i.a.
Spinal
cord
does
not
have
a
periosteal
Cerebrospinal
fluid
monitored
i.
Spaces
each
other
between
and
dural
with
the
layers
central
iii.
Permits
CSF
to
be
absorbed
into venous
i.
Deep
to
arachnoid
iii.
Pia
mater
(gentle
mother)
d.
Absorbed
into
venous
subarachnoid
space
a.
Facilitated
diffusion
ofcord
particular
substances
c.
layer
covers
brain
and
spinal
cord
b.Meningeal
Blood-brain
barrier
i.
Control
of
autonomic
ii.
Collect
canal
of
venous
the
spinal
blood
flow
from
brain
blood
ii.
Filled
with
CSF
i.
Lateral
apertures
blood
through
arachnoid
villi
i.
Glucose
and
others
d. Dura
projects
inward
to
help
anchor
the
brain
functions
iii.
Directs
blood
flow
back
to
jugular
veins
c.
Interventricular
foramen
iii.
Secured
to
pia
by
weblike
extensions
of
ii.
Median
aperture
b. Cannot
prevent
fat-soluble
molecules from
connect
lateral
with
third
the
arachnoid
diffuses
into brain
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BASIM ZWAIN LECTURE NOTES
Spinal Cord
Gross anatomy
Cross-sectional
Spinal
pathwaysanatomy
Meninges
Descending
(motor)
pathways
Gray
matter
and spinal
roots
a.
Single
layer
Protected
Dorsal root ganglion
Characteristics
a. Gray
is a.
organized
like a butterfly
Attachments
a. Upper
motor
neurons
i. Spinal
dural
sheath
Bone
Lateral
Ascending
horn
(sensory)
pathways
a.Most
Cell
bodies
of
sensory
neurons
d.i.Indirect
(tracts)—multi-neuronal
Meninges
Spinal
nerves
a.
pathways
decussate
Bridge—gray
commissure
a.
Denticulate
ligaments
b.
Epidural
space
i.(fasciculi
Vertebral
column
i. Cell
bodies
in
brain
Anterior
horn
a.
Dorsal
column
cuneatus
andneurons
gracilis)
a.
Cell
bodies
for
autonomic
motor
b.
Axons
project
to
cord
via
dorsal
root
a.
Dura
i.
Rubrospinal
b. Gray
matter
columns
a. Most
Lateral
of
ventral
and
dorsal
roots
i.fusion
Attached
to
vertebrae
laterally
Padding
of
fat
between
b.
are
poly-synaptic
b.
Membranes
b.
Lower
motor
neurons
a.
Cell
bodies
of
somatic
motor
neurons
Touch
and
proprioception
i.i.
Sympathetic
NS
b.
Arachnoid
i.
Some
enter
white
matter
tracks
and
i.or
Posterior
(dorsal)
horn
ii.
Vestibulospinal
b.
Filumi.neurons
terminale
vertebrae
and
dural
sheath
Meninges
b.
Part
of
PNS
i. b.
Two
three
i. Send
Cell via
bodies
inc.
anterior
horn
oflateral)
spinal cord
axons
via
ventral
root
Pia
b.
b.
Spinothalamic
Leave
ventral
(anterior
root
and
ii. i.
Anterior
(ventral)
horncaudally
ascend
Attached
to
coccyx
c.
Subarachnoid
space
iii.
Reticulospinal
c.
Fluid
c. Most
are mapped
c.
Direct
i.
Pain
and
temperature
iii. Tectospinal
Lateral
horn
(thoracic
and superior
i. synapse
Filled
withwith
CSF interneuron
i.
CSF
ii.
Some
located
iv.
i. Position
in
cord
reflects
location
on
body
i. lumbar
Anterior
and
lateral
(pyramidal)
regions
d. Extend
to only)
S2
in
posterior
horn
d. All
pathways
paired
corticospinal
tracts
i. Spinalare
cord
only extends to L1
Exit
BASIM ZWAIN LECTURE NOTES
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