Classification & divisions of the NS
Construct a flow chart on the last page of these notes. You will need to know each division and
the 2 pieces of info under each one. This will be a matching section. (on test – not on quiz)
Central Nervous System
I.
Protections of the Brain & Spinal cord (pg 463-470)
A. scalp & hair: ______________________________
B. bone: ____________________________________
C. meninges – see imbalance page 465
i.
epidural space: _________________________
ii.
dura mater - contain dural sinuses – collect venous blood & shunt to internal
jugular vein
iii. subdural space: _________________________
iv.
arachnoid______________________________
v.
subarachnoid space: _____________________
vi. pia mater:_____________________________
D. blood - brain barrier
i.
Function: ensures stable environment by endothelial tight junctions in blood
capillaries
ii.
excludes some substances while allowing other substances to freely pass :
List those that can pass through __________________________________
_____________________________________________________________
iii. not identical in all regions - ex. hypothalamus almost non-existent to sample
comp. of blood
iv. BBB is incomplete in newborns: May lead to kernicturus
______________________________________________________________
_____________________________________________________
II.
CSF (Cerebrospinal Fluid)
A.
functions
i.
support, protect, & exchange of materials
ii.
forms a cushion
iii.
circulating fluid to monitor levels of _____, _____, & ____ to trigger
feedback mechanisms if necessary to maintain homeostasis
B. location: subarachnoid space & 4 ventricles in brain & central canal
C. ~800 ml formed daily in the choroid plexus seeps from the capillaries and into
ventricles
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D. circulation pattern
_______________________________________________________________________
_______________________________________________________________________
_______________________________________________________________________
E. hydrocephalus - newborn vs. adult - see imbalance symbol pg 465-467
BRAIN ANATOMY (page 431431-454)
454)
Brain & spinal cord develops from neural tube
4 major regions: cerebral hemispheres, diencephalon, brain stem, and cerebellum
I.
Cerebral hemispheres (Cerebrum)
A.
surface
i.
gyri: ________________________________________
ii.
iii.
B.
sulci: ________________________________________
a)
Purpose: ____________________________________
b)
fissures: _____________________________________
(1)
longitudinal fissure: _________________________
(2)
transverse fissure: __________________________
(3)
lateral fissure: ______________________________
Lobes – named for bones they lie under
divisions
i.
Cerebrum
a)
cerebral cortex
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(1)
(2)
ii.
iii.
gray matter = cell_____________
(a)
thickness: ___________, _______% of brain mass
(b)
Function: voluntary motion, higher order thinking skills
Cerebral White Matter
(a)
corpus callosum - largest fiber tract connecting the
two hemispheres – if cut, left & right brain cannot
communicate
(b)
basal nuclei – located deep within the white matter islands of gray matter
(i)
indirectly help initiate and control slow,
stereotyped muscle movement
(ii)
ex. arm swinging while walking
Diencephalon
a)
located on _________________________
b)
enclosed by cerebral hemispheres
c)
Made of 3 parts:
(1)
________________________________________________
(2)
_______________________________________________
(3)
________________________________________________
Brain Stem
a)
attaches to spinal cord
b)
Controls the rigidly programmed automatic behaviors necessary for
__________________________________________
c)
iv.
Has 3 parts:
(1)
________________________________________________
(2)
________________________________________________
(3)
________________________________________________
Cerebellum
a)
Function – produce smooth, coordinated motions
b)
Damage results in ataxia: uncoordinated wavering motions
Complete the Brain Study Diagram at the back of these notes & study it.
End of Quiz #3 Material – does not include info
from function charts & WS
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Developmental Aspects of the CNS
1. Cerebral palsy (p. 482)
2. Alzheimer’s disease (p. 469)
3. Parkinson’s disease (p. 469)
4. Huntington’s disease (chorea) – p. 469-470
Make sure you know the Brain disorders (Flash Cards ONLY)
1. meningitis (p. 465)
2. encephalitis (p. 465)
3. cerebral edema (p. 468)
4. CVA (p. 468)
5. ischemia (p. 468)
6. TIA (p. 468)
7. multiple sclerosis (p. 407)
8. hemiplegia (p. 468)
Spinal Cord Anatomy (page 470470-472 in text)
See nerve structure diagram
I. Approximately ___________ long and extends from _________________________
to _________________________________ and is about the size of your
______________ for most of its length.
II. Meningeal coverings extend to the level of___________________________ (see
picture)
III. See nerve plexus diagram
IV. See Dermatome diagram.
V. What is the purpose of a lumbar (or spinal) tap? Why is this procedure done at the
level of L4 or L5? Why must the patient remain lying down for 6-12 hours after this
procedure (be specific as to why)?
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VI. Define the following:
1. Flaccid paralysis
2. Spastic paralysis
3. Quadriplegic
4. Paraplegic
5. Spina bifida-incomplete formation of vertebrae – folic acid reduces risk
1. Occulta-no external manifestations
2. Cystica-saclike cyst protrudes from spine
3. Meningocele-cyst contains meninges & CSF
4. Myelomeningocele-cyst also contains portions of spinal cord and nerve roots
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Nerve structure
Nerve Plexus
p. 498
Dermatomes:
These diagrams show
you the area of skin
supplied by the root of
each spinal nerve.
Pain in these skin
areas can tell you
about organ damage
going on. For
example: Damage to
the sciatic nerve will
manifest itself as pain
in the S2 area of your
leg since the sciatic
nerve comes out of the
sacral vertebrae.
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