Ch. 15 Nervous System Flashcards
The nervous system functions:
senses physical/chemical changes in internal/external environments, processes them, and then responds to maintain homeostasis.
coordinates, regulates, and integrates voluntary/ involuntary activities
The nervous system relies on:
transmission of electrochemical impulses throughout the body
afferent
Carry or move inward or toward a central structure
blood–brain barrier
Protective mechanism that blocks specific substances found in the bloodstream from entering delicate brain tissue
efferent
Carry or move away from a central structure
limbic system
Complex neural system located beneath the cerebrum that controls basic emotions and drives and plays an important role in memory
neurilemma
Additional external myelin sheath that is formed by Schwann cells and found only on axons in the peripheral nervous system
ventricle
Organ chamber or cavity that receives or holds fluid
two principal cell types
neurons and neuroglia
Neurons
transmit impulses
neurons and nerves are classified as
afferent (when the impulse moves toward the brain or spinal cord) or
efferent (when the impulse moves away from the brain or spinal cord)
The three major structures of the neuron are
the cell body, axon, and dendrites.
cell body
is the enlarged structure of the neuron that contains the (2) nucleus of the cell and various organelles.
axons
carry impulses from the cell body.
Axons are threadlike extensions of nerve cells that transmit impulses to dendrites of other neurons and to muscles and glands.
possess a white, lipoid covering called a (5) myelin sheath.
dendrites
branching cytoplasmic projections
carry impulses to cell body
resemble tiny branches on a tree, providing additional surface area for receiving impulses from other neurons.
myelin sheath
lipoid covering on axon (electrical insulator)
reduces impulse stimulating adjacent nerves
accelerates impulse transmission through axon
Schwann cell
forms myelin sheath on nerves in the peripheral nervous system
wraps tightly around the axon
exterior surface forms a thin tube called the (7) neurilemma, or neurolemma
neurilemma
acts as a protective coat for peripheral neurons. If the neurilemma covering remains intact after an injury to the nerve, it forms a tube that provides a pathway for possible neuron regeneration after injury.
Oligodendrocytes
form myelin sheath in CENTRAL nervous system
injuries to neurons irreparable (no neurilemma made)
nodes of Ranvier
short, unmyelinated spaces between myelin sheath
help speed the transmission of impulses down axon
synapse
functional connection between neuron and another neuron or it’s effector organ (muscle or gland)
includes transmitter site, synaptic cleft, and receptor site
neurotransmitter
chemical substance caused/released by axon
diffuses across the synapse
attaches to receiving neuron that immediately inactivates it
Neuroglia
means “nerve glue”
cells that supply nutrients & O2 to neurons
bind neurons to other neurons and body tissues
they do not transmit impulses
4 types of neuraglia:
astrocytes, oligodendrocytes, microglia, and ependyma.
Astrocytes
star-shaped neuroglia
three-dimensional mechanical support for neurons
form tight sheaths around the capillaries of brain
mildly phagocytic functions in brain/spinal cord
blood–brain barrier
sheaths formed by astrocytes
blocks large unwanted substances from brain tissue
considered when developing medicines
Oligodendrocytes
AKA oligodendroglia
develope myelin on axons in CENTRAL nervous system
Microglia,
the smallest of the neuroglia, possess phagocytic properties and become very active during times of infection.
Ependyma
ciliated cells that line fluid-filled cavities of CNS
especially ventricles of the brain
assist in the circulation of cerebrospinal fluid (CSF).
The two major divisions of the nervous system are
central & peripheral nervous system
The central nervous system consists of
all nervous tissue located in the brain and spinal cord.
The peripheral nervous system includes
all nervous tissue located outside the central nervous system and consists of cranial and spinal nerves.
Nervous System Structures
Central
- brain
- spinal cord
Peripheral
- cranial nerves
- spinal nerves
Brain
Center for thought and emotion, interpretation of sensory stimuli, and coordination of body functions
integrates almost every physical and mental activity of the body and is the center for memory, emotion, thought, judgment, reasoning, and consciousness.
Spinal Cord
Main pathway for transmission of information between the brain and body
Cranial nerves
12 pairs of nerves that emerge from the base of the skull and may act in a motor capacity, sensory capacity, or both
Spinal nerves
31 pairs of nerves that emerge from the spine and act in motor and sensory capacities
The central nervous system (CNS) consists of:
the brain and spinal cord
white matter - axon bundles w/ white lipoid myelin sheaths
gray matter - unmyelinated fibers, dendrites, nerve cell bodies
Review Lower Half of Figure 15-3
pg 518
The four major structures of the brain are the following:
- Cerebrum
- Cerebellum
- Diencephalon
- Brainstem
cerebrum
largest, uppermost portion with 2 hemispheres
sensory perception/interpretation, language, voluntary movement, and memory.
corpus callosum
joins these hemispheres, permitting communication between the right and left sides of the brain.
Each hemisphere consists of five lobes.
frontal parietal temporal occipital insula (internal)
gyri
the numerous folds (convolutions) of the cerebral surface
sulci
furrows, or fissures that separate the gyri
cerebral cortex
thin layer of gray matter that covers the entire cerebrum
processes information
limbic system
primitive “emotional: brain beneath the cerebrum
works with “thinking” brain
essential for survival
controls rage, fear, food enjoyment, sexual behavior
Mental/emotional illnesses result of chemical/electrical imbalance of limbic system.
Cerebellum
2nd largest structure of brain, posterior portion
movement, posture, balance.
The cerebrum initiates muscular movement and the cerebellum coordinates and refines it.
Diencephalon
interbrain
composed of thalamus and hypothalamus
thalamus
receives/processes all sensory stimuli (not olfactory)
transmits to appropriate centers in cerebral cortex
receives cerebrum impulses & relays to efferent nerves
hypothalamus
regulates involuntary activities (heart rate, body temp., fluid balance) and many endocrine functions.
Brainstem
composed of midbrain, medulla, and pons,
impulse conduction path btwn brain & spinal cord
origin of 10/12 pairs of cranial nerves
controls respiration, blood pressure, and heart rate
controls beginning of life (initiation of heartbeat )
and end of life (cessation of respiration/heart activity)
midbrain
AKA mesencephalon
separates cerebrum from brainstem
medulla
attaches to spinal cord
pons
AKA bridge
connects midbrain to medulla
Spinal Cord/ nerves
transmits sensory impulses from body to brain
and motor impulses from brain to muscles/organs
spinal nerves exit between intervertebral spaces
are identified by region of vertebral column
ascending tracts
sensory nerve tracts
the direction of the impulse is upward.
motor nerve tracts
carry impulses in a downward direction to muscles and organs.
3 meninges and general function:
provide limited protection of brain and spinal cord
dura mater
arachnoid
pia mater
dura mater
AKA pachymeninges.
outermost covering of brain/spinal cord.
tough, fibrous, dense connective tissue
subdural space
cavity beneath dura mater
filled with serous fluid
arachnoid
loosely fitting, spiderweb-like middle covering of brain & spinal cord
cerebrospinal fluid
sit in a subarachnoid space
colorless fluid of protein, glucose, urea, salt, WBC
circulates around/through spinal cord/brain
provides nutrients
acts as shock absorber
hydrocephalus
condition of any interference with the absorption of cerebral spinal fluid
results in a collection of fluid in the brain
pia mater
innermost meninx
adheres to brain/spinal cord
contains numerous blood vessels/lymphatics that nourish underlying tissues
leptomeninges
both the arachnoid and pia mater together
Read on Peripheral Nervous System
pg 520 - 523
Complete Lower Portion of Anatomy Review
pg 524
The main function of the nervous system
is to identify and respond to internal and external changes in the environment to maintain homeostasis.
Functional relationships between the nervous system and
Blood, Lymphatic, and Immune
- identifies/responds to changes in blood/lymph composition to maintain homeostasis.
- identifies pathologically altered tissue and assists immune system in containing injury and promoting healing.
Functional relationships between the nervous system and
Cardiovascular
- Nervous tissue, especially the conduction system of the heart, transmits a contraction impulse.
- The nervous system identifies pressure changes on vascular walls and responds to regulate blood pressure.
Functional relationships between the nervous system and
Digestive
- stimuli propel food by peristalsis.
* receptors identify need to defecate.
Functional relationships between the nervous system and
Endocrine
• The hypothalamus regulates hormone production.
Functional relationships between the nervous system and
Female Reproductive
- transmits contraction impulses for delivery
- provides stimuli needed for lactation
- regulates hormones for menstrual cycle
Functional relationships between the nervous system and
Integumentary
- environmental stimuli response
* body temperature regulation (shivering/sweating)
Functional relationships between the nervous system and
Male Reproductive
- regulates sexual responses
* provides pleasure responses through nervous tissue
Functional relationships between the nervous system and
Musculoskeletal
- impulses (contraction) resulting in voluntary/involuntary movement of muscles.
- Autonomic nervous tissue responds to positional changes.
Functional relationships between the nervous system and
Respiratory
- The nervous system stimulates muscle contractions that create the pressure changes necessary for ventilation.
- The nervous system regulates the rate and depth of breathing.
Functional relationships between the nervous system and
Urinary
- The nervous system stimulates the thirst reflex when body fluid levels are low.
- The nervous system regulates all aspects of urine formation.
cerebr/o
cerebrum
cerebr/o/tomy
incision of the cerebrum
crani/o
cranium (skull)
crani/o/malacia
softening of the cranium
encephal/o
brain
encephal/o/cele
hernia, swelling of the brain
gangli/o
ganglion (knot or knotlike mass)
gangli/ectomy
removal of the ganglion (knot or knotlike mass)
gli/o
glue; neuroglial tissue
gli/oma
tumor of neuroglial tissue
kinesi/o
movement
brady/kines/ia
condition of slow movement
lept/o
thin, slender
lept/o/mening/o/pathy
disease of thin, slender meninges (membranes covering the brain and spinal cord)
lex/o
word, phrase
dys/lex/ia
condition of bad, painful, difficult, word, phrase
mening/o
meninges (membranes covering the brain and spinal cord)
mening/o
meninges (membranes covering the brain and spinal cord)
mening/o/cele
hernia, swelling of the meninges (membranes covering the brain and spinal cord)
meningi/o
meninges (membranes covering the brain and spinal cord)
meninges (membranes covering the brain and spinal cord)
mening/o
meningi/o
meningi/oma
tumor of meninges (membranes covering the brain and spinal cord)
myel/o
bone marrow; spinal cord
poli/o/myel/itis
inflammation of the gray; gray matter and bone marrow; spinal cord
narc/o
stupor; numbness; sleep
narc/o/tic
pertaining to stupor; numbness; sleep
neur/o
nerve
neur/o/lysis
separation; destruction; loosening of nerve
radicul/o
nerve root
radicul/algia
pain of nerve root
sthen/o
strength
hyper/sthen/ia
condition of excessive, above normal strength
thalam/o
thalamus
thalam/o/tomy
incision of the thalamus
thec/o
sheath (usually referring to the meninges)
intra/thec/al
pertaining to within the sheath (usually referring to the meninges)
ton/o
tension
dys/ton/ia
condition of bad, painful, difficult tension
ventricul/o
ventricle (of the heart or brain)
ventricul/itis
inflammation of the ventricle (of the heart or brain)
-algesia
pain
an/algesia
pain without
-algia
pain
pain
- algesia
- algia
syn/algia
pain union, together, joined
-asthenia
weakness, debility
my/asthenia
muscle weakness, debility
-esthesia
feeling
hyper/esthesia
excessive, above normal feeling
-kinesia
movement
hyper/kinesia
excessive, above normal movement
-lepsy
seizure
narc/o/lepsy
sleep seizure
-paresis
partial paralysis
hemi/paresis
one-half partial paralysis
-phasia
speech
a/phasia
without speech
-plegia
paralysis
quadri/plegia
paralysis of four
-taxia
order, coordination
a/taxia
without order
pachy-
thick
pachy/mening/itis
inflammation of thick meninges (membranes covering the brain and spinal cord)
para-
near, beside; beyond
para/plegia
paralysis near, beside; beyond
syn-
union, together, joined
syn/algia
pain union, together, joined
Complete Learning Activity 15-1
pg 548
Complete Learning Activity 15-2
pg 549
dyskinesia
involuntary movement
Neurology
is the branch of medicine concerned with neurological diseases
neurologist
The physician who specializes in the diagnosis and treatment of nervous system disorders
Psychiatry
is the branch of medicine concerned with mental illnesses
psychiatrist.
The physician who specializes in diagnosing and treating mental illness
Disorders of the Nervous System
Cerebrovascular Disease
Seizure Disorders
Multiple Sclerosis
Mental Illness
Cerebrovascular Disease
group of disorders affecting the vessels that supply blood to the brain.
causes stokes
3 major types of stokes:
ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage
2 other terms for stoke:
cerebrovascular accident (CVA), or “brain attack
intracerebral hemorrhage
sudden rupture of an artery within the brain
subarachnoid hemorrhage
blood is released into the space between the brain and the tissues that surround the brain. This condition is commonly caused by a ruptured aneurysm and is usually fatal
ischemic stroke
are similar to that of a heart attack and include emboli, thrombi, and atherosclerosis that limit blood flow to brain tissue
transient ischemic attack (TIA)
aka mini stroke
type of stroke in which symptoms resolve within 24 hours and do not cause permanent damage. TIAs require immediate medical attention because they are often a precursor to a full-blown stroke.
ataxia
lack of muscle coordination
Seizure disorders
sudden changes in behavior/consciousness caused by uncontrolled electrical activity in brain
epileptic seizures and nonepileptic seizures
epileptic seizures
no known cause, are chronic, and occur repeatedly
nonepileptic seizures
triggered by disorders or conditions that irritate the brain.
These triggers commonly include brain injury, congenital anomalies, metabolic disorders, brain tumors, fever, vascular disturbances, and genetic disorders.
partial seizures
only a portion of the brain is involved. There is a short alteration of consciousness of about 10 to 30 seconds with repetitive, unusual movements and confusion.
generalized seizure
, the entire brain is involved. The most common type of generalized seizure is the tonic-clonic (grand mal) seizure
tonic-clonic (grand mal) seizure
. In tonic-clonic seizures, the body alternates between excessive muscle tone and rigidity (tonic) and jerking muscle contractions (clonic) in the extremities.
postictal event
After the seizure, such neurological symptoms as weakness, confusion, headache, and nausea may occur. These symptoms are called a postictal event, which commonly lasts for 5 to 30 minutes but may last longer with a severe seizure.
aura
Many patients experience a warning signal (aura) of an imminent seizure
Multiple sclerosis (MS)
autoimmune disease
targets CNS myelin sheath on nerves
impedes transmission of electrical impulses
Mental illness
includes an array of psychological disorders, syndromes, and behavioral patterns that cause alterations in mood, behavior, and thinking
clinical psychologists
individuals trained in evaluating human behavior, intelligence, and personality
affective disorder
Psychological disorder in which the major characteristic is an abnormal mood, usually mania or depression
anorexia nervosa
Eating disorder characterized by a refusal to maintain adequate weight for age and height and an all-consuming desire to remain thin
anxiety
Psychological “worry” disorder characterized by excessive pondering or thinking “what if…”
attention deficit-hyperactivity disorder (ADHD)
Disorder affecting children and adults and characterized by impulsiveness, overactivity, and the inability to remain focused on a task
autism
Developmental disorder characterized by extreme withdrawal and an abnormal absorption in fantasy, usually accompanied by an inability to communicate even on a basic level
bipolar disorder
Mental disorder that causes unusual shifts in mood, emotion, energy, and the ability to function; also called manic-depressive illness
q
bulimia nervosa
Eating disorder characterized by binging (overeating) and purging (vomiting or use of laxatives)
depression
Mood disorder associated with sadness, despair, discouragement and, commonly, feelings of low self-esteem, guilt, and withdrawal
mania
Mood disorder characterized by mental and physical hyperactivity, disorganized behavior, and excessively elevated mood
neurosis
Nonpsychotic mental illness that triggers feelings of distress and anxiety and impairs normal behavior
panic attack
Sudden, intense feeling of fear that comes without warning and is not attributable to any immediate danger
psychosis
Major emotional disorder in which contact with reality is lost to the point that the individual is incapable of meeting the challenges of daily life
primary intracranial tumors
Intracranial tumors that originate directly in brain tissue
papilledema
optic disc in the back of the eyeball swells
gnos
knowing
agnosia
Inability to comprehend auditory, visual, spatial, olfactory, or other sensations, even though the sensory sphere is intact
Alzheimer disease (AD)
Type of age-associated dementia caused by small lesions called plaques that develop in the cerebral cortex and interrupt the passage of electrochemical signals between cells; also called cerebral degeneration
anencephaly
Congenital deformity in which some or all of the fetal brain is missing
encephal:
brain
closed head trauma
Injury to the head in which the dura mater remains intact and brain tissue is not exposed
coma
Abnormally deep unconsciousness with an absence of voluntary response to stimuli
concussion
Traumatic injury to the brain that causes unconscoiousness and is commonly of a temporary nature
convulsion
Any sudden and violent contraction of one or more voluntary muscles that is commonly associated with such brain disorders as epilepsy
dementia
Broad term that refers to cognitive deficit, including memory impairment
ment:
mind
dyslexia
Inability to learn and process written language, despite adequate intelligence, sensory ability, and exposure
lex:
word, phrase
Guillain-Barré syndrome
Autoimmune condition that causes acute inflammation of the peripheral nerves damaging their myelin sheaths, resulting in decreased nerve impulses, loss of reflex response, and sudden muscle weakness; also called infective or idiopathic polyneuritis
herpes zoster
Acute inflammatory eruption of highly painful vesicles on the trunk of the body or, occasionally, the face that is caused by the same virus that causes chickenpox; also called shingles (See Fig. 15-7.)
Huntington chorea
CNS disorder characterized by quick, involuntary movements, speech disturbances, and mental deterioration; also called neurodegenerative genetic disorder
hydrocephalus
Accumulation of fluid in the ventricles of the brain, causing increased intracranial pressure (ICP), thinning of brain tissue, and separation of cranial bones
lethargy
Abnormal inactivity or lack of response to normal stimuli
myasthenia gravis (MG)
Chronic, progressive disorder in which a loss of neurotransmitter receptors produces increasingly severe muscle weakness (See Fig. 15-8.)
-asthenia:
weakness, debility
spina bifida
Congenital deformity of the neural tube (embryonic structure that becomes the fetal brain and spinal cord), which fails to close during fetal development; also called neural tube defect
meningocele
Form of spina bifida in which the spinal cord develops properly but the meninges protrude through the spine
myelomeningocele
Most severe form of spina bifida in which the spinal cord and meninges protrude through the spine
occulta
Form of spina bifida in which one or more vertebrae are malformed, and the spinal cord is covered with a layer of skin
palsy
Paralysis, usually partial, and commonly characterized by weakness and shaking or uncontrolled tremor
Bell palsy
Facial paralysis caused by a functional disorder of the seventh cranial nerve; also called facial nerve palsy
cerebral palsy (CP)
Type of paralysis that affects movement and muscle coordination and may affect gross and fine motor skills
paralysis
Loss of voluntary motion in one or more muscle groups with or without loss of sensation
paresthesia
Sensation of numbness, prickling, tingling, or heightened sensitivity
Parkinson disease
Degenerative disorder in which the progressive loss of brain cells leads to impairment in motor function, including tremors, muscular rigidity, and a slowing of movement; also called paralysis agitans or shaking palsy
poliomyelitis
Inflammation of the gray matter of the spinal cord caused by a virus, commonly resulting in spinal and muscle deformity and paralysis
poli/o:
gray; gray matter (of the
brain or spinal cord)
radiculopathy
Disorder affecting one or more nerves at the location where the nerve root exits the spine and commonly the result of a herniated or compressed disk, degenerative changes, arthritis, or bone spurs; also called radiculitis
radicul/o:
nerve root
Reye syndrome
Potentially fatal syndrome that commonly causes brain swelling and liver damage and is characterized by confusion, hyperventilation, violent behavior, seizures, and possibly coma; also called acute noninflammatory encephalopathy and fatty degenerative liver failure
syncope
Brief loss of consciousness and posture caused by a temporary decrease of blood flow to the brain; also called fainting
Complete Learning Activity 15-3
pg 551
electroencephalography (EEG)
Recording of electrical activity in the brain, whose cells emit distinct patterns of rhythmic electrical impulses (See Fig. 15-11, page 540.)
electromyography (EMG)
Recording of electrical signals (action potentials) that occur in a muscle when it is at rest and during contraction to assess muscular disease or nerve damage
lumbar puncture (LP)
Needle puncture of the spinal cavity to extract spinal fluid for diagnostic purposes, introduce anesthetic agents into the spinal canal, or remove fluid to allow other fluids (such as radiopaque substances) to be injected; also called spinal puncture and spinal tap (See Fig. 15-12.)
nerve conduction velocity (NCV)
Test that measures the speed at which impulses travel through a nerve
cerebrospinal fluid (CSF) analysis
vLaboratory test to examine a sample of the fluid surrounding the brain and spinal cord that helps diagnose disorders of the central nervous system, including viral and bacterial infections, tumors, and hemorrhage
computed tomography angiography (CTA, CT angiography)
Radiographic image of the interior of a vessel in combination with a CT scan to produce high-resolution, three-dimensional images of blood vessels
discography
CT scan of the lumbar region after injection of a contrast medium to detect problems with the spine and spinal nerve roots
echoencephalography
Ultrasound technique used to study intracranial structures of the brain and diagnose conditions that cause a shift in the midline structures of the brain
magnetic source imaging (MSI)
Noninvasive neuroimaging technique to pinpoint the specific location where seizure activity originates and enable custom surgical treatment for tumor and epileptic tissue resection; also called magnetoencephalography (MEG)
myelography
Radiographic examination to detect pathology of the spinal cord, including the location of a spinal cord injury, cysts, and tumors following injection of a contrast medium
positron emission tomography (PET)
Computed tomography that records the positrons (positively charged particles) emitted from a radiopharmaceutical and produces a cross-sectional image of metabolic activity of body tissues to determine the presence of disease
cryosurgery
Technique that exposes abnormal tissue to extreme cold to destroy it
thalamotomy
Partial destruction of the thalamus to treat intractable pain; involuntary movements, including tremors in Parkinson disease; or emotional disturbances
tractotomy
Transection of a nerve tract in the brainstem or spinal cord
trephination
Technique that cuts a circular opening into the skull to reveal brain tissue and decrease intracranial pressure
ventriculoperitoneal shunting
Relieves intracranial pressure due to hydrocephalus by diverting (shunting) excess cerebrospinal fluid from the ventricles into the peritoneal or thoracic cavity (See Fig. 15-13.)
intravenous (IV) tissue plasminogen activator (tPA)
Treatment for ischemic stroke using tissue plasminogen activator (tPA), a potent clot-busting drug, injected directly into a vein
plasmapheresis
Extracorporeal procedure to treat patients with autoimmune diseases by removing their plasma containing the offending antibodies and replacing it with donor plasma or plasma substitutes
stereotactic radiosurgery (SRS)
Procedure that uses three-dimensional imaging (stereotactic) along with high doses of highly focused radiation to destroy tumors and other abnormal growths in the brain, spinal column, and other body sites with minimal exposure to surrounding healthy tissue
anesthetics
Produce partial or complete loss of sensation, with or without loss of consciousness
general (anesthetics)
Act upon the brain to produce complete loss of feeling with loss of consciousness
local (anesthetics)
Act upon nerves or nerve tracts to affect only a local area
nerve block
anesthetics
Blocks pain from the area supplied by that nerve
anticonvulsants
Prevent uncontrolled neuron activity associated with seizures by altering electrical transmission along neurons or altering the chemical composition of neurotransmitters; also called antiepileptics
antiparkinsonian agents
Control tremors and muscle rigidity associated with Parkinson disease by increasing dopamine in the brain
antianxiety agents
React at distinct receptor sites in the limbic and cortical system to decrease anxiety
antipsychotics
Treat psychosis, paranoia, and schizophrenia by altering chemicals in the brain, including the limbic system, which controls emotions
antidepressants
Treat multiple symptoms of depression by increasing levels of specific neurotransmitters
hypnotics
Depress central nervous system (CNS) functions, promote sedation and sleep, and relieve agitation, anxiousness, and restlessness
psychostimulants
Reduce impulsive behavior by increasing the level of neurotransmitters
AD
Alzheimer disease
LP
lumbar puncture
AChR
acetylcholine receptor
MEG
magnetoencephalography
ADHD
attention deficit-hyperactivity disorder
MG
myasthenia gravis
CNS
central nervous system
MRI
magnetic resonance imaging
CP
cerebral palsy
MS
multiple sclerosis; mental status; musculoskeletal; mitral stenosis
CSF
cerebrospinal fluid
MSI
magnetic source imaging
CT
computed tomography
NCV
nerve conduction velocity
CTA
computed tomographyangiography
PET
positron emission tomography
CVA
cerebrovascular accident
PNS
peripheral nervous system
EEG
electroencephalography
SRS
stereotactic radiosurgery
EMG
electromyography
TIA
transient ischemic attack
ICP
intracranial pressure
tPA
tissue plasminogen activator
IV
intravenous
Complete Learning Activity 15-4
pg 552
The four major types of neuroglia are
astrocytes, oligodendrocytes, microglia, and ependyma.
