Chapter 10 Flashcards
caus/o
burning, burn
cerebr/o
cerebrum, brain
concuss/o
shaken together, violently agitated
contus/o
bruise
-esthesia
sensation, feeling
esthet/o
feeling, nervous sensation, sense of
perception
mening/o
membranes, meninges
myel/o
spinal cord, bone marrow
neur/i, neur/o
nerve, nerve tissue
phobia
abnormal fear
psych/o
mind
radicul/o
root or nerve root
tropic
having an affinity for
central nervous system
brain and spinal cord
ganglion
a nerve center made up
of a cluster of nerve cell bodies outside the central
nervous system (plural, ganglia or ganglions). Note: The
term ganglion also describes a benign, tumor-like cyst.
plexus
is a network of intersecting spinal nerves (plural, plexuses) (Figure 10.8A). This term also describes a network of intersecting blood or lymphatic vessels.
afferent neurons (towards)
Also known as sensory neurons, these neurons emerge from sensory
organs and the skin to carry the impulses from the sensory organs
toward the brain and spinal cord.
connective neurons
Also known as associative neurons, these neurons link afferent and
efferent neurons
Efferent neurons (away)
Also known as motor neurons, these neurons carry impulses away
from the brain and spinal cord and toward the muscles and glands.
dendrites
are the root-like processes
that receive impulses and conduct them to the cell body.
A process is a structure that extends out from the cell body.
axon
is a process that conducts impulses
away from the nerve cell. An axon can be more than
3 feet long. Many, but not all, axons are protected by a
myelin sheath, which is a white fatty tissue covering.
terminal end fibres
are the branching fibers at the
end of the axon that lead the nervous impulse from the
axon to the synapse.
synapse
is the space between two neurons
or between a neuron and a receptor organ. A single
neuron can have a few or several hundred synapses
Acetylcholine
is released at some synapses in the spinal
cord and at neuromuscular junctions; it influences
muscle action
dopamine
is released within the brain. It is believed to be
involved in mood and thought disorders and in abnormal
movement disorders such as Parkinson’s disease.
endorphins
are naturally occurring substances that
are produced by the brain to help relieve pain.
Norepinephrine
affects alertness and arousal, increasing
blood pressure and heart rate, and releasing stores
of glucose in response to stress. It is also a hormone
released by the adrenal gland as part of the body’s
fight-or-flight response
serotonin
which is released in the brain, has roles in
sleep, hunger, and pleasure recognition. It is also
sometimes linked to mood disorders.
glial cells
provide support and protection for
neurons, and their four main functions are (1) to surround
neurons and hold them in place, (2) to supply nutrients
and oxygen to neurons, (3) to insulate one neuron from
another, and (4) to destroy and remove dead neurons.
myelin sheath
is the protective covering
made up of glial cells. This white sheath forms the white
matter of the brain and covers some parts of the spinal cord
and the axon of most peripheral nerves
myelinated
having a myelin sheath
white matter
myelinated
grey matter
unmyelinated
meninges
are the system of
membranes that enclose the brain and spinal cord (singular
meninx). The meninges consist of three layers of
connective tissue. These are the dura mater, arachnoid
membrane, and the pia mater
dura mater
is the thick, tough,
outermost membrane of the meninges. Dura means
hard, and mater means mother.
n The inner surface of the cranium (skull) is lined with
the dura mater.
n The inner surface of the vertebral column is known
as the epidural space. This space, which is located
between the walls of the vertebral column and the
dura mater of the meninges, contains fat and supportive
connective tissues to cushion the dura
mater.
n In both the skull and vertebral column, the subdural
space is located between the dura mater and the
arachnoid membrane.
arachnoid membrane
which
resembles a spiderweb, is the second layer of the meninges
and is located between the dura mater and the pia
mater. Arachnoid means having to do with spiders.
n The arachnoid membrane is loosely attached to the
other meninges to allow space for fluid to flow
between the layers.
n The subarachnoid space, which is located below
the arachnoid membrane and above the pia mater,
contains cerebrospinal fluid.
pia mater
which is the third layer
of the meninges, is located nearest to the brain and spinal
cord. It consists of delicate connective tissue that contains
a rich supply of blood vessels. Pia means tender or delicate,
and mater means mother.
cerebrospinal fluid
also known
as spinal fluid, is produced by special capillaries within
the four ventricles located in the middle region of the
cerebrum (Figures 10.3 and 10.4). Cerebrospinal fluid is
a clear, colorless, and watery fluid that flows throughout
the brain and around the spinal cord. The functions of
this fluid are to:
n Cool and cushion these organs from shock or injury
n Nourish the brain and spinal cord by transporting
nutrients and chemical messengers to these
tissues
cerebrum
is the largest and uppermost
portion of the brain. It is responsible for all thought,
judgment, memory, and emotion, as well as for controlling
and integrating motor and sensory functions. Note
that cerebrum and cerebellum are similar words, but
refer to very different parts of the brain. Memory aid:
The cerebellum is below the cerebrum
cerebral cortex
which is made up of gray matter,
is the outer layer of the cerebrum and is made up of
elevated folds and deep fissures (Figure 10.6).
n Gyri (singular gyrus) are the elevated folds of gray
matter in the cerebral cortex.
n Sulci are the fissures of the cerebral cortex. As used
here, a fissure is a normally occurring deep groove.
Skin fissures, which are crack-like sores, are discussed
in
thalamus
Relays sensory stimuli from the spinal cord and
midbrain to the cerebral cortex. The thalamus suppresses
some stimuli and magnifies others.
hypothalamus
Controls vital bodily functions
1. Regulates and integrates the autonomic nervous system, including controlling heart rate, blood pressure,
respiratory rate, and digestive tract activity.
2. Regulates emotional responses, including fear and pleasure.
3. Regulates body temperature.
4. Regulates food intake by controlling hunger sensations.
5. Regulates water balance by controlling thirst sensations.
6. Regulates sleep-wakefulness cycles.
7. Regulates the pituitary gland and endocrine system activity
cerebellum
Coordinates muscular activity and balance for smooth
and steady movements
brainstem
Controls the functions necessary for survival
(breathing, digestion, heart rate, and blood pressure),
and for arousal (being awake and alert).
left cerebral hemisphere
controls the majority of
functions on the right side of the body. An injury to the
left hemisphere produces sensory and motor deficits on
the right side of the body
right cerebral hemisphere
controls most of the
functions on the left side of the body. An injury to the
right hemisphere produces sensory and motor deficits
on the left side of the bo
frontal lobe
controls skilled motor functions,
memory, and behavior.
parietal lobe
receives and interprets nerve
impulses from sensory receptors in the tongue, skin,
and muscles
occipital lobe
controls eyesight
temporal lobe
controls the senses of hearing and
smell, and the ability to create, store, and access new
information.
sy mpathetic nerves
prepare the body for emergencies
and stress by increasing the breathing rate, heart
rate, and blood flow to muscles. These nerves become
aroused as part of the fight-or-flight response, which is
the body’s natural reaction to real or imaginary danger.
parasympathetic
return the body to normal
after a response to stress. They also maintain
normal body functions during ordinary circumstances
that are not emotionally or physically stressful.
encephala/o
brain
coup
describes an injury occurring within
the skull near the point of impact, such as hitting the
windshield in an auto accident.
countercoup
counterblow
is an injury that occurs
beneath the skull opposite to the area of impact
syncope
fainting lack of blood to brain
stroke
This condition is
damage to the brain that occurs when the blood flow to the
brain is disrupted because a blood vessel is either blocked or
has ruptured. Strokes are currently the third-leading cause of
death and the primary cause of long-term disability.
The location of the disruption determines the symptoms
that will be present.
ischemic
disruption of blood supply
narc/o
stupor
poliomyelitis
also
known as polio, is a highly contagious viral infection
of the brainstem and spinal cord that sometimes
leads to paralysis (poli/o means gray matter, myel
means spinal cord and bone marrow, and -itis
means inflammation). There is no known cure for
polio; however, it can be prevented through
vaccination
multiple sclerosis
is a progressive autoimmune
disorder characterized by inflammation that
causes demyelination of the myelin sheath. This scars
the brain, spinal cord, and optic nerves and disrupts the
transmission of nerve impulses. This damage leaves the
patient with varying degrees of pain plus physical and
cognitive problems.
sciatica
is inflammation of the sciatic
nerve that results in pain, burning, and tingling along
the course of the affected sciatic nerve through the
thigh, leg, and foot
siezure
is a sudden surge of electrical
activity in the brain that affects how a person feels or acts
for a short time. Some seizures can hardly be noticed,
whereas others cause a brief loss of consciousness. Seizures
are symptoms of different disorders that can affect
the brain and also can be caused by extreme high fever,
brain injury, or brain lesions.
paresthesia
refers to a burning
or prickling sensation that is usually felt in the hands,
arms, legs, or feet, but can also occur in other parts of
the body (par- means abnormal, and -esthesia means
sensation or feeling). These sensations may constitute
the first symptoms of peripheral neuropathy or may be
a drug side effect.
lumbar puncture spinal tap
process of obtaining a sample of cerebrospinal fluid by
inserting a needle into the subarachnoid space of the
lumbar region to withdraw fluid. Changes in the
composition of the cerebrospinal fluid can be an indication
of injury, infection, or disease
barbiturates
are a class of drugs
whose major action is a calming or depressed effect on
the central nervous system.
n Amobarbital is a barbiturate used as a sedative and
hypnotic.
n Phenobarbital is a barbiturate used as a sedative
and as an anticonvulsant
agoraphobia
an excessive
fear of environments where the person fears a panic
attack might occur. In order to avoid these situations,
someone suffering from agoraphobia might not even
be able to leave home (agor/a means marketplace,
and -phobia means abnormal fear)
factitious
means artificial, self-induced, or not naturally
occurring. Visible symptoms are self-inflicted and
seem motivated by a desire for attention and sympathy
rather than for external benefits like malingering (see
the later section “Somatoform Disorders
trichotillomania
repetedly pulling out ones own hair
manic behaviour
includes an abnormally elevated
mood state, including inappropriate elation, increased
irritability, severe insomnia, poor judgment, and
inappropriate social behavior
somatoform disorder
is characterized
by physical complaints or concerns about one’s
body that are out of proportion to any physical findings or
disease
conversion disorder
is characterized by serious
temporary or ongoing changes in function, such as
paralysis or blindness, that are triggered by psychological
factors rather than by any physical cause
malingering
is characterized by
the intentional creation of false or grossly exaggerated
physical or psychological symptoms. In contrast to a
factitious disorder, this condition is motivated by
incentives such as avoiding work.
