Chapter 10
Nervous System
Copyright © 2008, 2005 by Saunders, an imprint of Elsevier Inc. All rights reserved.
The Nervous System
Central Nervous System
Brain
Spinal Cord
Peripheral Nervous System
Cranial Nerves
Spinal Nerves
Autonomic Nervous System
Sympathetic Nerves
Parasympathetic Nerves
1
Introduction
Nervous system:
 Complex:
10 billion nerve cells
 Voluntary
and involuntary functions
 Nerves
carry electrical messages
 External
and internal receptors
2
Introduction (cont’d.)
Nerve cells:
 Microscopic
 Collected
 Carry
into macroscopic nerves
electrical messages all over the
body
3
Nervous System
Two major divisions:
 Central nervous system


Brain
Spinal cord
 Peripheral


nervous system
cranial nerves
spinal nerves
4
General Structure of the
Nervous System (cont’d.)
 Cranial



and spinal nerves
Sensory nerves carry messages toward the
brain.
Motor nerves carry messages from the brain.
Mixed nerves carry both sensory and motor
fibers.
 Sensory
receptors
5
parasympathetic and sympathetic nerves
6
General Structure of the
Nervous System (cont’d.)
Autonomic nervous system:

Carries impulses from the central nervous
system to organs.

The autonomic nervous system contains a large
group of nerves that function automatically.

It controls heart, blood vessels, glands, and
involuntary muscles like intestines, and hollow
organs such as stomach and urinary bladder.
7
Automomic Nervous System

Sympathetic nerves stimulate body under
stress.

Parasympathetic nerves balance sympathetic
system.



Slow heart rate
Lower blood pressure
https://www.youtube.com/watch?v=H8ItFuDgYKw
8
Divisions of the Central and
Peripheral Nervous System –
page 346
9
Neurons, Nerves, and Glia
Neuron = individual nerve cell
 Dendrite
 Cell
– branching fibers of neuron
nucleus
10
Neurons, Nerves, and Glia
 Axon


– carry impulses away
Myelin sheath – fatty tissue that covers the
axon giving it a white color (white matter)
Gray Matter – cell bodies of neurons not
covered with a myelin sheath.
11
Neurons, Nerves, and Glia

Synapse – space where nervous impulse jumps
from one neuron to another

Terminal end fibers - (secrete neurotransmitters)

Neurotransmitters - transfer impulse across
synapse

Ganglia - small clusters of nerve cell bodies outside
the brain and spinal cord.
12
Neurotransmitters – chemicals that
control the transfer of an impulse across
the synapse
 Acetylcholine
 Norepinephrine
 Epinephrine
 Dopamine
 Serotonin
 Endorphins
13
Image shows the
parts of a neuron.
Review the path
of a nervous
impulse.
14
Neurons, Nerves, and Glia (cont’d.)
Glia cells:
Maintain health of nervous system
Do not transmit impulses
15
Four Types of Glial Cells – p. 348
(astroglial cells) – transport
H20 and salts
 Astrocytes
(microglial cells) – protect
neurons in response to inflammation
 Microglia
(oligodendroglial cells) –
form myelin sheath.
 Oligodendroglia
–line membranes in the brain
and spinal cord.
 Ependymal

These are the supportive, protective, and connective cells of the
central nervous system.
16
Glial cells
17
The Brain p. 348– Controls body
activities, weighs about 3 lbs
18
The Brain
 The
brain is divided into right and left
hemispheres.
 The brain consists of four major lobes,
including the frontal lobe, parietal lobe,
temporal lobe, and occipital lobe.
 http://study.com/academy/lesson/parts-of-
the-brain.html
19
The Cerebrum

Largest section of brain

Surface has nerve cells called cerebral cortex.

Manages speech, vision, smell, movement,
hearing, and thought
20
Cerebrum – page 350
 Spaces
in the middle of the cerebrum are
called ventricles.
 Ventricles
contain cerebrospinal fluid
(CSF). This fluid cushions the brain.
 CSF
can be removed for testing or relief of
pressure on the brain.
21
The Brain
22
The Brain
 Cerebellum


Coordinates voluntary movements
Maintains balance
23
The Brain
 Thalamus

Integrates and monitors impulses from skin
(pain)
24
 Hypothalamus



Controls body temperature, sleep, appetite,
sexual desire, and emotions
Regulates release of hormones from
pituitary gland
Monitors sympathetic and parasympathetic
25
nervous systems
The Brain
The Brainstem
 Pons


Bridges cerebrum and cerebellum with rest of
the brain
Houses nerves for face and eyes
26
The Brainstem (cont’d.)
 Medulla

oblongata
Connects spinal cord to brain

Nerve tracts from side to side

Regulates:
• Blood vessels
• Heart
• Respiratory system
27
Pons and Medulla
28
Thyroid Gland
29
The Spinal Cord and Meninges
page 351
Spinal cord
30
Spinal Cord
 The
spinal cord is the column of nervous
tissue from the medulla oblongata to
second lumbar vertebra.
 It serves as a pathway for impulses to and
from the brain.
 The inner section of the cross-section of
the spinal cord is gray matter.
 The outer section of the cross-section of
the spinal cord is white matter.
31
Meninges
Meninges: Meninges are the three layers of
connective tissue membranes that
surround the brain and spinal cord.
32
Meningitis
 https://www.youtube.com/watch?v=FHLW
nlrmKNg
33
VOCABULARY-page 353

Acetylcholine – neurotransmitter released at
nerve cells

afferent nerves – Carry messages toward brain
and spinal cord

Arachnoid membrane – Middle meninges layer
34
VOCABULARY-page 353
Astrocyte – type of nerve cell that transports
water and salts from capillaries
autonomic nervous system – controls
involuntary body functions
35
VOCABULARY- pg 353
 Axon
– microscopic fiber that carries the
nervous impulse along a nerve cell.
 blood-brain
barrier – capillaires that
selectively let certain substances enter brain
tissue and keep others out.
36
VOCABULARY- pg 353
Brainstem – lower portion brain containing
pons and medulla.
cauda equina – collection of spinal nerves
below the end of the spinal cord.
cell body – part of nerve cell that contains
the nucleus
37
VOCABULARY- pg 353

central nervous system – brain and spinal cord

Cerebellum – posterior part of brain that
coordinates muscle movements and maintains
balance.

cerebral cortex – outer region of brain;containing
sheets of nerve cells; gray matter of the brain
38
VOCABULARY- pg 353
fluid (CSF) – Fluid that
circulates throughout brain and spinal cord
 cerebrospinal
– largest part of brain
responsible for voluntary muscle activity,
vision, speech, taste, hearing, thought,
and memory.
 Cerebrum
39
VOCABULARY- pg 353-354

Dendrite – microscopic branching fiber of a nerve cell
that is the first part to receive the nervous impulse

dura mater – thick, outermost layer of the meninges
surround and protecting the brain and spinal cord

efferent nerves – carry messages away from brain
and spinal cord.
40
VOCABULARY – page 354
 Hypothalamus
 medulla
–
oblongata –
– 3 protective layers that
surround brain and spinal cord
 Meninges
41
VOCABULARY – page 354
nerves – carry messages away
from brain and spinal cord to muscles and
organs. (efferent)
 motor
sheath – White fatty tissue that
surrounds, and insulates the axon of the
nerve cell. Myelin speeds conduction
along axons
 myelin
42
43
VOCABULARY- page 354
– nerve cells that carries
impulses throughout the body
 Neuron
– chemical
messenger released at the end of a
nerve cell that stimulates or inhibits
another nerve, muscle, or gland cell.
 Neurotransmitter
44
VOCABULARY- page 354
parasympathetic nerves –
Involuntary, autonomic nerves that
regulate normal body functions such
as HR, breathings and muscles of GI
tract
peripheral nervous system –
Cranial, spinal, and autonomic nerves,
nerves outside the brain and spinal
cord.
45
46
VOCABULARY – pg 355
 pia
mater – Thin, delicate inner membrane of
meninges
 Plexus
– interlacing network of nerves
 Receptor
– organ that receives a nervous
stimulation and passes it on to nerves within
the body.
47
48
VOCABULARY – pg 355
 sciatic
nerve – nerve extending from the
base of the spine down the thigh, lower
leg, and foot.
 Spinal
nerves – 31 pairs of nerves arising
from the spinal cord.
49
50
51
VOCABULARY- pg 355
nerves – Autonomic nerves
that influence bodily functions involuntarily
in times of stress
 sympathetic
nerve – 10th crainial nerve. Leaves
the lead and wanders into abdominal and
thoracic cavitites.
 Vagus
of the brain – Canals in the
brain that contain cerebrospinal fluid
 ventricles
52
53
QUICK QUIZ:
1. A sheet of nerve cells that
produces a rounded fold on
the surface of the
cerebellum
A.
B.
C.
D.
microglial
gyrus
parenchyma
stroma
54
QUICK QUIZ:
2. The thin, delicate inner
membrane of the meninges
A.
B.
C.
D.
pia mater
dura mater
parenchyma
stroma
55
COMBINING FORMS
page 356
Combining Form
 cerebell/o
Meaning
cerebellum

 cerebr/o
cerebrum
 dur/o
dura mater

Subdural hematoma
56
Nervous System
 encephal/o



Encephalitis
Encephalopathy
Anencephaly
 gli/o

brain
glial cells
Glioblatoma – highly malignant tumor
57
Nervous System
58
Combining Forms p. 357
Combining Form
Meaning
 lept/o
thin, slender
 mening/o
membranes,
meninges
 my/o
muscle
 myel/o
spinal cord
59
Combining Forms
 neur/o
nerve
 pont/o
pons
 radicul/o
nerve root
60
COMBINING FORMS p. 357-358
Combining Form
Meaning
 thalam/o
thalamus
 thec/o
sheath (refers to
meninges)
 vag/o
vagus nerve
61
page 358-359
Combining Form
 alges/o,
algesia
Meaning
Sensitivity to pain
 algia
Pain
 caus/o
Burning
62
Combining Forms
Deep sleep
 comat/o
 esthesi/o,
 esthesi/a
Feeling, nervous
sensation
 kines/o,
movement
-kinesia
63
COMBINING FORMS
page 359 - 360
Combining Form
Meaning – word use
 -kinesis,
(bradykinesia)
kinetic
 -lepsy
(epilepsy)
 lex/o
(dyslexia)

64
Combining Forms
Combining Form
Meaning – word use
 -paresis
(hemiparesis)
 -phasia
(aphasia)
65
page 360-361
Combining Form
Meaning
 -plegia
Paralysis
 -praxia
Action
 -sthenia
Strength
66
Combining Forms
Combining Form
Meaning – word use
 syncop/o
cut off
 tax/o
order, coordination
67
QUICK QUIZ:
3. Which term means nerve
pain?
A.
B.
C.
D.
cephalgia
analgesia
hypalgesia
neuralgia
68
QUICK QUIZ:
4. Which type of hematoma occurs
between the skull and the dura
as a result of a ruptured
meningeal artery, usually after a
fracture of the skull?
A. subdural
B. epidural
C. intracerebral
69
Pathologic Conditions – p 361
 Hydrocephalus
 Spina
bifida
 Spina bifida cystica
 Spina bifida occulta
70
Meningomyelocele
71
Degenerative, Movement, and
Seizure Disorders p. 363-364




Alzheimer disease
(AD)
Amyotrophic lateral
sclerosis (ALS)
Epilepsy
Huntington disease

Multiple sclerosis
(MS)

Myasthenia gravis
(MG)

Palsy

Parkinson disease

Tourette syndrome
72
73
Bell Palsy
74
Infectious Disorders – page 366
 Herpes
zoster (shingles)
 Meningitis
 Human
immunodeficiency virus (HIV)
encephalopathy
75
Neoplastic Disorders page 367
76
Traumatic Disorders – page 367
 Cerebral

concussion:
Temporary brain dysfunction after
injury, usually clears within 24
hours
77
Cerebral Contusion
Bruising of brain
tissue through
direct trauma to
head

Neurological
deficits persist
longer than 24
hours
78
CVA cerebral vascular accident –
page 368
 Thrombotic
— blood clot in artery leaving
to the brain
— dislodged clot that travels to
cerebral arteries
 Embolic
— a blood vessel, such as
the cerebral artery breaks, and bleeding
occurs
 Hemorrhagic
79
Vascular Disorders
80
Clinical Procedures – page 371
X-ray Tests



Cerebral angiography
Computed tomography (CT) of the
brain
Myelography
81
Clinical Procedures – page 371


MRI - Magnetic resonance Imaging
MRA - Magnetic resonance
angiogram

PET - Positron emission scan

EEG - Electroencephalography
82
Lumbar Puncture (LP)
 A needle
is inserted in the spinal cord for
removal of CSF.
83
MRA and MRI
84
MRI
85
CT Scan
86
PET scan reveals the cellular level metabolic
changes occurring in an organ or tissue.
87
PET Scan - Positron Emission
Tomography
 The
red color shows the highest level of
glucose utilization, yellow represents less
utilization and blue shows the least.
88
Abbreviations page 374
Abbreviations
 AD
Alzheimer disease
 AFP
alpha-fetoprotein

 ALS
amyotrophic lateral sclerosis

 AVM
arteriovenous malformation
89
Abbreviations – page 374
CNS
central nervous system
CT
computed tomography
CVA
cerebrovascular accident
CSF
cerebrospinal fluid
90
Abbreviations
 EEG
Electroencephalogram
 GABA
gamma-aminobutyric acid
 ICP
intracranial pressure
 LP
lumbar puncture
91
Abbreviations
 MAC
monitored anesthetic care
 MG
myasthenia gravis

 MRA
 MRI
magnetic resonance
angiography
magnetic resonance
imaging
92
Abbreviations

1/2 P
 PET

 Hemiparesis
 positron
emission
tomography
 Sz
 Seizure
 TBI
 traumatic
brain injury
93
Abbreviations
 TENS
 TIA
 tPA
 transcutaneous
electrical
nerve stimulation
 transient
ischemic attack
 tissue
plasminogen
activator
94