Analyze the anatomy and physiology of the nervous system.
Specific Objectives:
Explain the structure of the brain, spinal cord, and nerves.
Analyze the function of the nervous system.
Discuss characteristics and treatment of common nervous
system disorders.
Complete “My definition” column of
use your brain
• Page 7 in you pkt!
Bell
• Describe the function of the nervous
system
Function
• Central nervous system
• Communication and coordination system
of the body
• Seat of intellect and reasoning
• Communication and
coordination system
of the body
• Seat of intellect and
reasoning
• Consists of the brain,
spinal cord, and
nerves
• Nerve cell
• Transmits a message
from one cell to the next
• Has a nucleus,
cytoplasm, and cell
membrane
• .Nucleus- “brain’ for
control of cell’s metabolic
activities and cell division
• .Mitochondrion-site of
cellular respiration, and
energy production, stores
ATP.
Nerve Cell (Neuron)
• DENDRITES
• Nerve cell processes
that carry impulse to
cell body
• May be one or many
• AXON
• Carries impulse away
from cell body
• Only one on a neuron
Bell
• Label B in packet
• Myelin Sheath /Neurilemma
Covering that speeds up the
nerve impulse along the axon
• Myelin is a fatty substance that
protects the axon
• Schwann cells white fatty
substance that wraps itself
around some axons.
• Nodes of Ranvier indentions
between Schwann cells
• Neuroglia-Supporting cells that
hold the neuron together.
“Glia“is Greek for glue.
Bell
• Describe the function of a:
– Dendrite
– Axon
– Neuron
– What are the 2 main divisions of the nervous
system?
Message/Impulse
• SYNAPSE –area where messages go from one
cell to the next
• Synaptic cleft space between neurons
• Nerve impulse – A STIMULUS creates an
IMPULSE. The impulse travels into the neuron
on the dendrite(s) and out on the axon. At the
end of the axon, a NEUROTRANSMITTER is
released that carries the impulse across the
SYNAPSE, to the next dendrite.
• 100 billion neurons in the brain
Different Types of Neurons
• SENSORY NEURONS
(AFFERENT) – emerge from
the skin or sense organs, carry
impulses to spinal cord and
brain
• MOTOR NEURONS
(EFFERENT) – carry
messages from brain and
spinal cord to muscles and
glands
• ASSOCIATIVE NEURONS
(INTERNEURONS) – carry
impulses from sensory
neurons to motor neurons
Membrane Excitability
text page 149
• A neuron membrane is….
• 1) At rest: large amt of potassium K+ ions inside and
with few Sodium ( Na+) with them. Is a negative charge.
• …here comes a sensory neuron receptor STIMULATED
example sound!
• 2) Na+ rushes in = action potential, creating
depolarization and a positive charge.
• 3) Next the gates open again and the K+ rushes back in
= repolarization
• This is repeated throughout the membrane over the
entire nerve.
• 1) Irritability- ability to react when
stimulated
• 2) Conductivity- ability to transmit a
stimulus to another point.
Sensory Pathway of CNS
• CENTRAL NERVOUS
SYSTEM – brain and spinal
cord
• PERIPHERAL NERVOUS
SYSTEM – cranial nerves and
spinal nerves
– AUTONOMIC NERVOUS
SYSTEM – includes peripheral
nerves and ganglia, supplies
heart muscle, smooth muscle
and secretory glands,
involuntary action
Testing for Reflexes
•
•
•
•
•
•
•
•
•
•
•
•
•
Working in teams of two, have students take turns to carry out each activity.
1.
Clap hands loudly about two feet in front of your partner’s eye.
What reaction occurred?
___________________________________________
2.
Have your partner sit on a stool or on top of a desk. Using the side of your
hand
or a reflex hammer, tap the leg just below the knee.
What reaction occurred?
3.
Look at your partner pupils with the light on. Describe their size and shape.
Turn the light in the room off.
What happened to the pupils?
4.
Have your partner stand in a doorway and ask him/her to press back of hands
against the side of the door as hard as possible for 30 seconds. Step away and
release arms.
What happened to the arms?
________________________________________
Discuss which division of the nervous system is involved in reflex reactions.
• 3 lb mass of soft nervous
tissue
• 100 billion neurons
• Protected by skull, three
membranes called meninges,
and cerebrospinal fluid
• Adequate blood supply is
needed, brain tissue will die in
4-8 mins without O2
• Divided into 4 major parts:
cerebrum, diencephalon,
cerebellum, brain stem
• List the layers of the MENINGES)
Coverings of the Brain
(MENINGES)
•
DURA MATER – outer brain covering,
lines the inside of the skull, tough
dense fibrous connective tissue.
•
SUBDURAL SPACE – between dura
and arachnoid
•
ARACHNOID – middle layer,
resembles fine cobweb,
•
PIA MATER – covers the brain’s
surface, comprised of blood vessels
held together by connective tissue
•
SUBARACHNOID SPACE - between
arachnoid and pia mater,filled with
CEREBROSPINAL FLUID – acts as a
liquid shock absorber and source of
nutrients for the brain.
bell
• Fill in the real definition….on Use your
Brain grid for
• Meninges
• Dura mater
• Arachnoid
• Pia mater
CEREBROSPINAL FLUID
page 155
• Forms inside ventricles of the brain
• Serves as a liquid shock absorber protecting the
brain and spinal cord
• BLOOD-BRAIN BARRIER – choroid plexus
capillaries prevent substances (like drugs) from
penetrating brain tissue – this makes infections,
like meningitis, difficult to cure
• LUMBAR PUNCTURE – removal of CSF from
spinal canal, needle puncture between 3rd and
4th lumbar vertebrae
Ventricles of the Brain
See page 143
•
•
•
•
•
Brain contains four cavities filled with cerebrospinal fluid called CEREBRAL
VENTRICLES….4 cavities
Right and left lateral ventricles
Third ventricle – behind and below the lateral ventricles
Fourth ventricle is below the 3rd, in front of the cerebellum and behind the
pons and medulla oblongata
CHOROID PLEXUS – network of blood vessels lining the ventricles which
helps in the formation of cerebrospinal fluid
•
•
Largest part of the brain
Divided into R and L hemispheres-Left
control right side of body and Right controls
left side of body….by deep groove
(longitudinal fissure)
•
CONVOLUTIONS – elevated folds on the
surface of the cerebrum, they increase the
surface area of the brain
SULCI – fissure or grooves separating
cerebral convolutions
Divided into four lobes – FRONTAL,
PARIETAL, OCCIPITAL and TEMPORAL
•Parietal
Frontal
•Temporal
•Occipital
•
•
Cerebral function: Conscious thought,
judgment, memory, reasoning, and will
power.
Bell
• Define/describe (does not matter which
column) on Use your brain:
– 1st eight terms
Location and Function
Cerebral Lobes, Brainstem, & Cerebellum
Memory/tidbit
• The storage site for memory depends on
the type of memory being stored.
For example-runningmotor area
• What you see while running-visual area
Assignment/bell…
•
•
•
•
Textbook pages 168
Answer 1-4,6,7 and 8
Complete Matching
Make sure all cerebrum/lobe functions did
you draw in cerebellum and stem? are
labeled for The Brain
Bell…
• One each sticky note: Name the 4 lobes
of cerebrum
• List @ least 2 things things/functions that
occur there
CEREBELLUM
• Located behind the pons and below the
cerebrum
• Composed of two hemispheres
• Controls all body functions related to skeletal
muscles, including:
• Balance
• Muscle tone
• Coordination of muscle movements
Bell
• List each lobe of the cerebrum plus the
cerebellum and all of the functions
Diencephalon=Located between cerebrum and midbrain
Composed of THALAMUS and HYPOTHALAMUS (pix 147)
THALAMUS: acts as a relay station for incoming and outgoing nerve
impulses
Vital functions of the
HYPOTHALAMUS:
Autonomic nervous
control
Temperature control
Appetite control
Emotional state
Sleep control (+BP, heartbeat,
H2O balance, Oxytocin. GI.
Mind over body)
Workbook
• Workbook Page 102-103 O
• Complete the brainy Puzzler (crossword)
• Made up of PONS, MEDULLA
and MIDBRAIN
• Pathway for ascending and
descending tracts
CONCIOUSNESS
• Pons – in front of cerebellum,
between midbrain and medulla
– contains center that controls
respiration
• Midbrain – vision and hearing
• Medulla oblongata – bulbshaped structure between
pons and spinal cord, inside
the cranium above foramen
magnum. Responsible for:
• Heart rate
Video clip
• http://www.youtube.com/watch?v=UfC4u5
GCy3I
bell
•
•
Complete Workbook Page 102-N
On 5 strips of paper write Hypothalamus,
Write function(s) of each
1)
2)
3)
4)
5)
Midbrain
Thalamus
Medulla
Pons
Hypothalamus
Label
– Label as follows….
1)Frontal
2)Occipital
3)Temporal
4)Parietal
5)Cerebellum
6)Brain stem
Bell
•
•
Matching page 156 text
Create 10 long strips of paper
–
Label as follows….
1)
2)
3)
4)
5)
6)
7)
8)
9)
10)
Frontal
Occipital
Hypothalamus
Temporal
Parietal
Cerebellum
Thalamus
Medulla
Pons
midbrain
assignment…..
• Answer 9 and 10 mult choice on page 168
in text
• Workbook page, 102 N and O
• Label midsagital diagram of brain( circled
terms only)
• Strip-activity
• Complete real definitions- Use your Brain
Bell
•
•
•
•
•
•
Study functions and structures of….
Diencephalon
Thalamus
Hypothalamus
Pons
Medulla oblongata
Bell
• 1) What are the 2 divisions of the
Diencephalon?
• 2) What is the job of the thalamus?
• 3) List at least 4 of the functions of the
hypothalamus?
• 4) Workbook page, 102 N and O
• Begins at foramen
magnum and continues
down to 2nd lumbar
vertebrae
• White and soft, in spinal
canal
• Surrounded by
cerebrospinal fluid
• Functions as:
• Reflex center
• Conduction pathway to
and from the brain
• Pg. 166
Peripheral Nervous System
All of the nerves of the body and ganglia
Autonomic nervous system is specialized
part of PNS
• Bundle of nerve fibers
enclosed by connective
tissue
• Sensory(A) nerves carry
impulses to brain and
spinal cord
• Motor nerves(E) carry
impulses to muscles or
glands
• Mixed nerves(I) contain
both sensory and motor
fibers
• Spinal nerves
• Originate at spinal
cord and go through
openings in vertebrae
• 31 pairs of spinal
nerves
• All are mixed nerves
• Named in relation to
their location on the
spinal cord
• AUTONOMIC NERVOUS
SYSTEM
• Regulates activities of visceral
organs
• Not subject to conscious
control
• SYMPATHETIC NERVOUS
SYSTEM – the “fight or flight”
system – when the body
perceives danger, SNS sends
message to adrenal medulla to
secrete adrenaline – heartbeat
increases
• PARASYMPATHETIC
NERVOUS SYSTEM –
counters effects of SNS,
decreases heart rate
Close up….
•
•
•
•
•
•
•
•
•
•
•
•
Olfactory
Optic
Oculomotor
Trochlear
Trigeminal
Abducens
Facial
Vestibulocochlear
Glossopharyngeal
Vagus
Accessory
Hypoglossal
•
•
Page 174
Workbook 109 B
•
•
•
12 pairs that originate in different
areas of the brain
They are designated by number
and name.
The name may give you a clue as
to its function
Can't remember the names of
the cranial nerves?
• Here is a handy dandy mnemonic for you:
• On Old Olympus Towering Top A
FamousVocal German Viewed Some
Hops.
• The bold letters stand for: olfactory,
optic,oculomotor,trochlear,trigeminal,
abducens,
facial,vestibulocochlear,glossopharyngeal,
vagus, spinalaccessory, hypoglossal.
• Reflex
• Unconscious and involuntary
• Like one way streets, impulse conduction only in
one direction
• In a simple reflex, only a sensory nerve and
motor nerve involved – example, “knee-jerk”
reflex, blink of an eye when dust touches , smell
something good and you start to salivate.
•
Bell…
• Text 156
• Theory to practice #2.
NC Health Careers Book
PICK 2 that Interest YOU!
•
•
•
•
•
•
•
•
•
•
•
•
•
Social Worker
Pharmacist
Pharm Tech
Occupational Therapist
OT Assistant
Speech Language Pathologist
Speech Assistant
Electroneurodiagnostic
Technologist
EMT
Physical Therapist
Physical Therapist Assistant
Recreational Therapist
Rehabilitation Counselor
•
•
•
•
•
•
Rubric (20 points each)
Job Description
Academic Requirements
Work Environment
Salary Range
At least 2 educational
programs
Test Date
• Thursday!...04/14
Bell…
• Workbook:
• page 99F
• page 110, C …number paper 1-8
Bell….
• First fill in the blanks on outline so you
can……
• Complete the grid for Neurological (see
packet) disorders, may use text and notes
• outline
Disorders of the Nervous
System
•
•
•
•
MENINGITIS
EPILEPSY
Cerebral Vascular Accident
ALZHEIMER’S DISEASE
MENINGITIS

Inflammation of the lining of the
brain and spinal cord

May be bacterial or viral

Symptoms – headache, fever
and stiff neck

In severe form, may lead to
paralysis, coma and death
• If bacterial, may be treated with antibiotics
EPILEPSY





•
Seizure disorder of the brain, characterized
by recurring and excessive discharge from neurons

Seizures believed to be result of
spontaneous, uncontrolled electrical activity of neurons

Cause – uncertain

Victim may have hallucinations and seizures

Grand mal – severe, convulsive seizure
Petit mal – milder
ALZHEIMER’S DISEASE
 
Progressive disease that begins with problems
remembering
 
Nerve endings in cortex of brain degenerate and block
signals that pass between nerve cells
 
Abnormal fibers build up creating tangles
 
Cause – unknown
 
First stage (2-4 years) involves confusion, short-term
memory loss, anxiety, poor judgment
 
2nd stage (2-10 years) increase in memory loss, difficulty
recognizing people, motor problems, logic problems, and loss of
social skills
 
3rd stage (1-3 years) inability to recognize oneself, weight
loss, seizures, mood swings and aphasia
Cerebral Vascular Accident
•
•
•
•
Stroke or CVA
Interruption of blood and O2 to brain
Tissue death
Third leading cause of death in USA
• Requires a large team of rehabilitation
specialists
CVA
Slurred
Speech
HTN
CVA
Athersclerosis
Hemiplegia
• Journal Highlights: Silent Stroke
See also the following articles related to silent
stroke recently published in Stroke AHA journals:
• Prevalence and Correlates of Silent Cerebral
Infarcts in the Framingham Offspring Study,
Seshadri et al.
• Brain Microbleeds and Global Cognitive
Function in Adults without Neurological Disorder,
Yaksuhiji et al.
• World Stroke Day
Wednesday, October 29, 2008
• The Joint World Stroke Congress — an organization composed of
health organizations from around the world including the American
Heart Association and the American Stroke Association — has
declared every October 29th to be World Stroke Day.
• On that day every year, the World Stroke Congress comes together
on a unified message intended to educate the world public about the
treatment and prevention of stroke.
• In 2008, World Stroke Day will focus on silent stroke, which occurs 5
times as often as other strokes, without the usual warning signs or
symptoms. This year’s World Stroke Day theme is “Little strokes, big
trouble.”
Risk Factors
for CVA
§
§
§
§
Smoking
Hypertension
Heart disease
Family history
•
Causes of CVA
• 90% caused by blood clots
•
• Clots lodge in carotid arteries, blocking
the flow of blood to the brain
•
• 10% caused by ruptured blood vessels
in the brain
Symptoms
§
§
§
§
§
§
§
§
Hemiplegia on opposite side of the body
Sudden, severe headache
Dizziness
Sudden loss of vision in one eye
Aphasia
Dysphasia
Coma
Possible death
Treatment
• 1.
Get to the hospital
immediately!!
• 2.
CT done to determine etiology
• 3.
If a clot, treatment aimed at
dissolving clot
Prevention
•
If TIAs – one aspirin a day
• Stop smoking
•
• Exercise and lose weight
•
• Control hypertension
•
Cerebral Palsy
• Causes muscles to function incorrectly
although they have normal intelligence.
May be caused by hypoxia at birth
Bell…..
• From workbook, answer Q 1-10 page 103.
Agenda for today
•
•
•
•
•
Use PP handouts to fill in disease grid
Watch movie
study for test
Nap
…not in that order
Bell
• Complete Q and R page 103 in workbook.