2. Intro to the Nervous System
Nervous System has 2 types of cells:
1. Neuron
2. Glial cells – support cells
3. Neuron
Basic structural unit of the nervous system
Maintains function of the nervous tissue
It is the nerve cell. myelin is ‘whiteish’ color
4. Glial Cells
Glial (glue) or neuroglial cells are the helper cells
They support the Neuron, more glials than neurons
Involved in the nutrition and maintenance of the
nerve cells
5. Parts of a Neuron
The soma (cell body) - contains the nucleus of the
cell which is the control center
Dendrite - receives the message and sends it to the
soma
Axon - sends the message to the muscle, next neuron
etc.
Axon terminal- end of the axon
6. Neurons (con’t)
The axon is covered by myelin sheath – this is a lipid
covering to protect the axon- like a jelly roll
Synapse- is the space between neurons- impulses
coming from one axon to the next “jump” to get to the
dendrite
8. Synapse Discussion
Briefly Study this Picture:
Turn to your neighbor and
discuss what you see.
dopamine is ‘feel good’
neurotransmitter
9. Functions of the nervous system
1. constantly monitors info from outside and
inside the body via receptors
2. perceives info in the brain; based on memory
3. evaluates info - detects heat
4. sends out motor direction- either a reflex or
you consciously jerk your hand away from heat, or
both
5. memory- to remember a learned behavior
Information is monitored, received, perceived,
evaluated, a response is sent, and the event is
stored in memory.
10. Nervous system
CNS - central nervous
system=brain/spinal cord
PNS - peripheral nervous
system=cranial nerves, spinal
nerves. PNS has
afferent(sensory)and
efferent(motor) nerves.
PNS has somatic nerv syst and
visceral nerv syst.
Somatic NS has afferent and
efferent nerves.
visceral nerv syst has afferent and
motor(autonomic NS)
ANS has sympathetic and
parasympathetic, motor only
11. CNS
Central Nervous System controls the brain,
spinal cord
• Brain controls many functions like:
sleep, sexual activity, memory, emotion,
movement, hunger thirst and thought
processes.
• Spinal Cord extends nerve fibers from the
brain and acts as a switching or relay
terminal for the peripheral nervous system.
12. PNS
Peripheral Nervous System
- controls cranial, spinal and
autonomic nerve
- 31 pairs exit from the spinal cord.
- each has a posterior and anterior
branch
a. posterior carries info to the
spinal cord (afferent)
b. anterior carries impulses to the
muscles (efferent)
13.
14. ANS(aka visceral motor division
Contains Sympathetic and Parasympathetic systems
Sympathetic= fight or flight- you may feel fear or anger-
you are reacting to an emergency
Increased heart rate
Liver releases & increases glucose
Thyroid is stimulated-sweating
Kidney vessels constrict
15. ANS (con’t)
Jane was walking and a dog started running at her
and barking.
Discuss with your partner:
Which part of the ANS would you say was activated?
What would some signs be?
17. ANS (con’t)
Albert was sitting in class and he heard his stomach
growl.
Discussion:
Which ANS system was activated?
What signs did he present?
18. Anatomy of the Brain(100billion neurons)
Cerebrum----who is Abby norm Al?
largest highest section of the brain
the outer part is arranged in folds called convolutions.
dips are sulci, raises are gyri
responsible for reasoning, thought, memory, speech,
sensation, sight, smell, hearing and voluntary body
movement
https://www.youtube.com/watch?v=nY1aB9w1zMc
19. Anatomy of the Brain
Cerebellum
section just below the cerebrum
responsible for muscle coordination, balance and
posture, and muscle tone
20. Anatomy of the Brain
Diencephalon
the section located between the
cerebrum and midbrain
divided into 2 sections:
1. Thalamus-acts as a relay center and directs sensory
impulses to the cerebrum
2. Hypothalamus- controls the ANS,
temperature, appetite, water balance,
sleep, blood vessel constriction and
dilation
21. Anatomy of the Brain
Midbrain
located below the cerebrum at the top of the brain
stem.
responsible for conducting impulses certain eye and
auditory reflexes
22. Anatomy of the Brain
Pons
located below the midbrain in the brain stem.
conducts messages to other parts of the brain - reflex
actions like chewing, tasting, saliva production, and
assisting with respirations
23. Anatomy of the Brain
Medulla oblongata
lowest part of the brain stem
connects brain with the spinal cord
responsible for regulating heartbeat, respirations,
swallowing, coughing, and blood pressure
24. Anatomy of the Brain
Spinal Cord
continues down from the medulla
oblongata to the 1st
or 2nd
lumbar vertebrae
surrounded by vertebrae
responsible for many reflex actions
carries sensory or afferent messages up to
the brain
takes efferent messages from the brain
through nerves to tissues
25. Anatomy of the Brain
Meninges
three membranes cover the brain and protect the spinal
cord (PAD---pia,arachnoid,dura)
1. dura mater - thick tough outer layer
2. arachnoid membrane - middle layer that is delicate
like a web
3. pia mater - attaches to the brain and spinal cord-
contains vessels that nourish the nerve tissue
26.
27. Anatomy of the Brain
Ventricles
4 hollow spaces in the brain
connect with each other and with the
space under the arachnoid membrane
(subarachnoid space)
filled with cerebrospinal fluid(CSF)that circulates
between the ventricles and through the subarachnoid
space
fluid acts as a shock absorber to protect the brain and
spinal cord.
28. Anatomy of the Brain
Choroid Plexus
structures that produce the cerebrospinal fluid
Arachnoid villi- absorb the cerebrospinal fluid and
return to the blood stream.
32. Pathology of the brain
Hemorrhage-an artery bursts and bleeds into
surrounding tissues. Blood pools and begins to clot,
and forms a hematoma.
This is considered a stroke or cerebrovascular
accident or CVA
This puts pressure on other parts of the brain
This reduces circulation to the other portions of the
brain and brain tissue dies
33.
34. pathologies
Causes of hemorrhage-
Trauma- mostly for under 50
High blood pressure- over prolonged time weakens
vessel walls
Aneurysm- weakening of a blood vessel wall that
swells- it can burst
35. pathologies
Signs and symptoms of hemorrhage-
Sudden severe headache
Seizure with no history of seizures
Weakness in arm or leg
Nausea and vomiting
Difficulty speaking
Loss of coordination
36. pathology
Treatment- must reduce the swelling in the brain
Medications to stop vomiting
Steroids to reduce swelling
Surgery to remove the clot
Diuretic to reduce swelling
37. Pathologies of neurology
Cerebral palsy- lack of O2 to the brain, birth injuries,
German Measles, and infections can cause CP
It is a disturbance in voluntary muscle action
There may also be problems with sensation, depth
perception, and communication ability. Difficulty with
cognition and epilepsy is found in about one-third of
cases.
38.
39. Pathology-cerebral palsy
Signs and symptoms:
stiff or tight muscles and exaggerated reflexes
(spasticity); walking with one foot or leg dragging;
walking on the toes, a crouched gait, or a “scissored”
gait; and muscle tone that is either too stiff or too
floppy
40. pathology
There is no cure for CP
Physical therapy and occupational therapy
Botox shots in spastic muscles
Muscle relaxants
41. pathology
Guillain-Barre syndrome is a disorder in which the
body's immune system attacks part of the peripheral
nervous system.
>the immune system starts to destroy the myelin
sheath that surrounds the axons of many peripheral
nerves, or even the axons themselves
paralyis starts at hands and legs, works toward the
trunk.
42. pathologies
treatment of GB- immunoglobulin- a donor protein
that helps decrease allergic reaction of the body.
Steroids to decrease inflammation
Watch for respiratory distress, patients can become
passive in about 3 weeks after onset
GB is not contagious
Diagnose with NCV test or CSF test
45. pathology
Absence seizures- petite mal- loss of consciousness
for a few seconds
Tonic clonic- grand mal- very severe with loss of
consciousness lasting seconds to minutes.
46.
47. pathology
Signs and symptoms of grand mal seizures
Thrashing movements
Hypersalivation
Violent shaking
Foaming at the mouth
Loss of body functions
48. pathology
Treatment- during seizure put the patient on their
side to avoid aspiration
Patient will look ashen-this is normal
Start CPR if the patient stops breathing
Give anticonvulsant therapy to help control
52. pathology
Multiple sclerosis- a progressive disabling condition
resulting from degenerating myelin sheath
Usually see this in people of their 20-40’s
Cause is unknown
53.
54. pathology
Signs and symptoms of MS
Visual disturbance
Weakness
Fatigue
Poor coordination
Tingling and numbness
Can lead to tremors spasticity and incontinence