The nervous system : Anatomy and Physiology
afferent neurons (afferent means toward)
Alzheimer's disease
disorder associated with degenerative changes in the
brain structure that lead to progressive memory loss, impaired cognition, and
personality changes
amyotrophic lateral sclerosis (ALS) a degenerative disease in which patients
become progressively weaker until they are completely paralyzed; also known as
Lou Gehrig's disease
anesthesia the absence of normal sensation, especially sensitivity to pain, that is
induced by the administration of an anesthetic
anesthetic the medication used to induce anesthesia
anticonvulsant administered to prevent seizures such as those associated with
epilepsy
antidepressant a medication administered to prevent or relieve depression
antipsychotic drug a medication administered to treat symptoms of severe
disorders of thinking and mood that are associated with neurological and
psychiatric illnesses such as schizophrenia, mania, and delusional disorders
anxiolytic drug a medication administered to temporarily relieve anxiety and to
reduce tension; also known as an antianxiety drug or tranquilizer
aphasia the loss of the ability to speak, write, and/or comprehend the written or
spoken word
attention deficit disorder characterized by a short attention span and impulsive
behavior that is inappropriate for the child's developmental age
autism describes a group of conditions in which a young child cannot develop
normal social relationships
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autonomic nervous system controls the involuntary actions of the body
axon a process that extends away from the cell body and conducts impulses away
from the nerve cell
barbiturates a class of drugs whose major action is a calming or depressed effect
on the central nervous system
Bell's palsy temporary paralysis of the seventh cranial nerve that causes drooping
only on the affected side of the face
brainstem the stalk-like portion of the brain that connects the cerebral
hemispheres with the spinal cord; made up of three parts: the midbrain, pons,
and medulla
carotid ultrasonography an ultrasound study of the carotid artery to detect
plaque buildup in the artery to predict or diagnose an ischemic stroke
centrall nervous system (CNS) includes the brain and spinal cord
cerebellum the second-largest part of the brain, located at the back of the head
below the posterior portion of the cerebrum
cerebral pertaining to the cerebrum or to the brain
cerebral hemispheres the cerebrum is divided into these two parts
cerebral lobes each cerebral hemisphere is subdivided to create pairs of lobes;
each lobe is named for the bone of the cranium that covers it
cerebral palsy a congenital condition characterized by poor muscle control,
spasticity, speech defects, and other neurologic deficiencies
cerebrospinal fluid a clear, colorless, and watery fluid that flows throughout the
brain and around the spinal cord
cerebrovascular accident damage to the brain that occurs when the blood flow to
the brain is disrupted; also known as a stroke
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cerebrum the largest and uppermost portion of the brain, consisting of four lobes
complex regional pain syndrome pain that occurs after an injury to an arm or a
leg, a heart attack, stroke, or other medical problem
Concussion a violent shaking up or jarring of the brain that may result in a
temporary loss of awareness and function
connecting neurons associative neurons which link sensory and motor neurons
conversion disorder 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
cranial hematoma a collection of blood trapped in the tissues of the brain
cranial nerves 12 pairs of nerves that originate from the undersurface of the brain
dementia a slowly progressive decline in mental abilities, including memory,
thinking, and judgment, that is often accompanied by personality changes
dendrites the root-like processes that receive impulses and conduct them to the
cell body
dyslexia a learning disability characterized by substandard reading achievement
due to the inability of the brain to process symbols; also known as a
developmental reading disorder
echoencephalography the use of ultrasound imaging to diagnose a shift in the
midline structures of the brain
efferent neurons (efferent means away from)
motor neurons which carry impulses away from the brain and spinal cord and
toward the muscles and glands
electroencephalography the process of recording the electrical activity of the
brain through the use of electrodes attached to the scalp
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encephalitis an inflammation of the brain
epidural anesthesia regional anesthesia produced by injecting a local anesthetic
into the epidural space of the lumbar or sacral region of the spine
epilepsya chronic neurological condition characterized by recurrent episodes of
seizures of varying severity
factitious disorder a condition in which an individual acts as if he or she has a
physical or mental illness when he or she is not really sick; previously known as
Munchausen
ganglion a nerve center made up of a cluster of nerve cell bodies outside the
central nervous system
glial cells provide support and protection for neurons
Gullain-Barre syndrome an inflammation of the myelin sheath of peripheral
nerves, characterized by rapidly worsening muscle weakness that may lead to
temporary paralysis; also known as infectious polyneuritis
hemorrhagic stroke occurs when a blood vessel in the brain leaks or ruptures; also
known as a bleed
hydrocephalus a condition in which there is an abnormally increased amount of
cerebrospinal fluid within the ventricles of the brain
hyperesthesia a condition of excessive sensitivity to stimuli
hypnotherapy the use of hypnosis to produce a relaxed state of focused attention
in which the patient may be more willing to believe and act on suggestions
hypnotic depresses the central nervous system and usually produces sleep
hypothalamus located below the thalamus, controls vital bodily functions
impulse-control disorders a group of psychiatric disorders characterized by the
inability to resist an impulse despite potential negative consequences
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innervations the supply of nerves to a specific body part
intracranial pressure the amount of pressure inside the skull
ischemic stroke a type of stroke that occurs when the flow of blood to the brain is
blocked
lobectomy surgical removal of a portion of the brain to treat brain cancer or
seizure disorders that cannot be controlled with medication
lumbar puncture the process of obtaining a sample of cerebrospinal fluid by
inserting a needle into the subarachnoid space of the lumbar region to withdraw
fluid
lumbar radiculopathy nerve pain in the lower back caused by muscle spasms or by
nerve root irritation from the compression of vertebral disks such as a herniated
disk
magnetic resonance imaging (MRI) and computer tomography (CT) important
neuroimaging tools because they facilitate the examination of the soft tissue
structures of the brain and spinal cord
medulla located at the lowest part of the brainstem, connected to the spinal cord
meninges the system of membranes that enclose the brain and spinal cord of the
CNS
meningitis an inflammation of the meninges of the brain or spinal cord
meningocele the congenital herniation of the meninges that surround the brain or
spinal cord through a defect in the skull or spinal column
midbrain and pons provides conduction pathways to and from the higher and
lower centers in the brain
multiple sclerosis a progressive autoimmune disorder characterized by scattered
patches of demyelination of nerve fibers of the brain and spinal cord
myelin sheath the protective covering made up of glial cells
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myelitis an inflammation of the spinal cord; also inflammation of bone marrow
myelography a radiographic study of the spinal cord after the injection of a
contrast medium through a lumbar puncture. The resulting record is called a
myelogram.
myelosis a tumor of the spinal cord
narcolepsy a sleep disorder consisting of recurring episodes of falling asleep
during the day
nerve one or more bundles of neurons that connect the brain and the spinal cord
with other parts of the body
neurons the basic cells of the nervous system that allow different parts of the
body to communicate with each other
neuroplasty the surgical repair of a nerve or nerves
neurorrhaphy surgically suturing together the ends of a severed nerve
neurotomy a surgical incision or the dissection of a nerve
neurotransmitters chemical substances that make it possible for messages to
cross from the synapse of a neuron to the target receptor; examples include
acetylcholine, dopamine, endorphins, norepinephrine, and serotonin
obsessive-compulsive disorder an anxiety disorder characterized by recurrent,
unwanted thoughts or impulses
panic attack a group of intense emotional feelings that include apprehension,
fearfulness, and terror
panic disorder an anxiety disorder characterized by unexpected and repeated
episodes known as panic attacks
parasympathetic nervous system returns the body to normal after a response to
stress
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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
Parkinson's disease (PD) a chronic, degenerative central nervous disorder in which
there is a progressive loss of control over movement, resulting in tremors and a
shuffling gait
peripheral nervous system (PNS) includes the 12 pairs of cranial nerves extending
from the brain and the 31 pairs of peripheral spinal nerves extending outward
from the spinal cord
peripheral neuropathy a painful condition of the nerves of the hands and feet due
to damage to the peripheral nerves; also known as peripheral neuritis
peripheralspinal nerves 31 pairs of spinal nerves that are grouped together and
named based on the region of the body they innervate
phenobarbital a barbiturate used as a sedative and as an anticonvulsant
poliomyelitis a highly contagious viral disease; also known as polio
psychotropic drug acts primarily on the central nervous system, where it produces
temporary changes affecting the mind, emotions, and behavior
radiculitis an inflammation of the root of a spinal nerve that causes pain and
numbness radiating down the affected limb; also known as a pinched nerve
receptors sites in the sensory organs that receive external stimulation
restless legs syndrome (RLS) a neurological disorder characterized by
uncomfortable feelings in the legs, producing a strong urge to move them
Reye's syndrome (RS) a potentially fatal condition that has been linked to giving
aspirin to children suffering from viral infections
SAM neuron functions: Sensory neurons (afferent); Associative neurons
(connecting); Motor neurons (efferent)
sciatica inflammation of the sciatic nerve
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sedative depresses the central nervous system to produce calm and diminished
responsiveness without producing sleep
seizure a sudden surge of electrical activity in the brain that affects how a person
feels or acts for a short time
somatoform disorder characterized by physical complaints or concerns about
one's body that are out of proportion to any physical findings or disease
somnambulism the condition of walking or performing some other activity
without awakening; also known as sleepwalking
spinal cord a long, fragile tube-like structure that begins at the end of the brain
stem and continues down almost to the bottom of the spinal column
sympathetic nervous system prepares the body for emergencies and stress by
increasing the breathing rate, heart rate, and blood flow to muscles
synapse the space between two neurons or between a neuron and a receptor
organ
syncope the brief loss of consciousness caused by the decreased flow of blood to
the brain; also known as fainting
tetanusan acute and potentially fatal infection of the central nervous system
caused by a toxin produced by the tetanus bacteria
thalamuslocated below the cerebrum, produces sensations by relaying impulses
to and from the cerebrum and the sense organs of the body
transient ischemic attack (TIA) the temporary interruption in the blood supply to
the brain
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