Transcript Central Nervous System

I. Spinal cord A. Cross section
• 1. anterior median
fissure
• 2. posterior median
sulcus
• 3. white matter-three
columns or funiculi
• 4. gray matter
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a. Anterior
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b. Posterior
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c. Gray commissure
5. dorsal root ganglion
6. dorsal root
7. ventral root
B. Locations of function with regard to the
spinal cord
• 1. dorsal root ganglionpseudo-unipolar neurons
• 2. anterior gray horn
• 3. lateral gray horn
• 4. ventral gray horn
• 5. ventral root
• 6. spinal nerve is mixed
• 7. interneuron
II. Reflex arcs
A. Five basic parts
• 1. sensory
receptor
• 2. afferent
neuron
• 3. association/
interneuron
• 4. motor neuron
• 5. effector
• 6. traits
• a. Automatic
• b. Unconscious
• c. Homeostatic
• d. Mono vs.
polysynaptic
B. Three types of reflexes
1. Simple stretch reflex
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a.
b.
c.
d.
Monsynaptic
Ipsilateral
Intrasegmental
Patellar reflex
2. Withdrawl reflex
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a. Polysynaptic
b. Ipsilateral
c. Intersegmental
d. Reciprocal
innervation
3. Crossed extensor reflex
• a. Polysynaptic
• b. Contralateral
• c. intersegmental
III. Structure of nerves
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A.
B.
C.
D.
Epineurium
Perineurium
Endoneurium
Fasicle
IV. Spinal cord and dermatomal map
V. Functional Anatomy of the Brain
A. Introduction
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1. difficult to talk about
2. two fistfuls of pinkish/gray
3. wrinkled
4. consistency of cold
oatmeal
• 5. three pounds
• 6. hugely complex
• 7. four basic regions
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a.
b.
c.
d.
Cerebral hemispheres
Diencephalon
Brain stem
cerebellum
B. Cerebral hemispheres
• 1. most important part
• 2. overshadows
diencephalon and brain
stem
• 3. mushroom cap covers
top of stalk
• 4. gyri
• 5. sulci
• 6. fissures-ie longitudinal
cerebral fissure
• 7. Lateral cerebral fissure
C. Parts of cerebrum
1. Frontal lobe
• a. Frontal lobe
controls mainly motor
function
• b. Primary motor area
is on the precentral
gyrus -governs
conscious motor
control which can be
mapped
Motor homunculus
c. Motor homunculus
• -specific regions of
the precentral
gyrus control
specific body parts
• -finer the
movements, the
more brain area
needed to control
those movements
d. Premotor area
• -learned
repetitive
tasks
• Typing,
playing piano
• Athletes
learn tasks
by visualizing
motions
• Ingrained in
this area
e. Broca’s area
• speech center
• Usually located left cerebral hemisphere
• Damage here causes inability to speak
f. Prefrontal area
Motivation
Planning
Emotional behavior
Moods
One Flew Over the
Cuckoo’s Nest
2. Parietal lobe-mainly sensory and association
function
• a. Post central gyrus mimics
the precentral gyrus except
that it is sensory in function
• b. Sensory information is
directed to the postcentral
gyrus where it reaches
conscious level
• c. Seems to be upside down
as you progress laterally
• d. projection
e. Other primary sensory areas
• Taste area
• Olfactory area
• Primary
auditory
cortex
• Visual cortex
f. Association areas
• Second stop for sensory
signals
• Directed from primary
sensory areas to
association areas
• Association area compares
present stimulus to
previous experience
• Process of recognition
3. Basal Nuclei of cerebrum
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a.
b.
c.
d.
e.
A nucleus is an area of gray matter within CNS
Deep in cerebral hemispheres are basal nuclei
Concerned with gross motor movements
Arms swinging and posture
Parkinson’s disease is a basal nuclei disorder
C. Diencephalon
1. Thalamus
a. Encloses third vent.
b. Screens incoming
sensory messages
2. Hypothalamus
a. ANS center for body
temperature and water
balance
b. Regulates pituitary
3. Epithalamus
a. Pineal gland
b. Choroid plexus
4. Role of thalamus is like a switchboard
operator
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Cerebrum
Fig. 14.8
Tertiary
neuron
Thalamus
Midbrain
Secondary
neuron
Pons
Dorsal root ganglion
Medulla oblongata
Primary neuron
cell body
Primary neuron
Spinothalamic
tract of
anterolateral
system
Spinal cord
Free nerve
endings
Interneuron
Gray
commissure
White
commissure
D. Brain stem
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1.
2.
3.
4.
size of thumb
midbrain
pons
medulla
5. medulla
• a. Reflex centers for
heart rate, blood vessel
diameter, respiration,
swallowing, vomitting etc
• b. Anterior surfacepyramidal tracts
• c. Decussation of motor
nerves consciously
controlling voluntary
function
6. pons
• a. Name means “bridge”
• b. Contains fiber tracts
specifically between
cerebrum and cerebellum
• c. Basically an interchange
• d. Also contains nuclei for
cranial nerves
• e. nuclei of respiratory reflex
7. midbrain
a. Corpora quadrigemina
• b. superior and inferior
colliculi
• Reflex centers for vision
and hearing
E. Cerebellum
1. Cauliflower
shape
2. Controls
balance and
equilibrium
3. Produces
smooth and
coordinated
muscular
contractions
4. Arbor vitae
F. Miscellaneous topics
1. Limbic system
• a. The limbic system is a
complex set of structures
that lies on both sides of
the thalamus, just under
the cerebrum.
• b. It includes the
hypothalamus, the
hippocampus, the
amygdala, and several
other nearby areas.
• c. It appears to be
primarily responsible for
our emotional life, and
has a lot to do with the
formation of memories.
2. Reticular Activating System (RAS)
• a. Regulates sleepwake cycles
• b. Works with
thalamus to focus
attention
• c. May be involved
with ADHD
3. Corpus callosum
a. Commisural fibers
b. Connects right and left
c. Right side of brain is
spatial and artistic
d. Left side of brain is
analytical and
mathematical
e. Two talk to each other
through the corpus
callosum
f. http://www.youtube.com/
watch?v=lfGwsAdS9Dc
VI. Protection of the
brain
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A. Meninges
1. dura mater
2. arachnoid
3. pia mater
B. CSF
1. produced
choroid plexi
• 2. flow
• 3. functions
• 4. hydrocephalus