Chapter 12 - Nervous System and Mental Health
paresthesia
abnormal sensation such as burning or tingling
hyperesthesia
abnormally heightened sense of feeling, pain, or touch
analgesia
absence of pain
cerebrovascular accident (CVA)
also called a stroke; development of infarct due to loss in blood supply to area of brain; blood flow can be interrupted by ruptured blood vessel (hemorrhage), floating clot (embolus), stationary clot (thrombosis), or compression; extent of damage depends on size and location of infarct and often includes speech problems and muscle paralysis
sulci
also called fissures; grooves that separate gyri of the cerebral cortex
peripher/o
away from center
vertebral canal
bony canal through vertebrae that contains spinal cord
encephal/o
brain
parasympathetic nervous system
branch of autonomic nervous system; serves as counterbalance for sympathetic nerves; therefore, it causes heart rate to slow down, lowers blood pressure, constricts eye pupils, and increases digestion
sympathetic nervous system
branch of autonomic nervous system; stimulates body in times of stress and crisis by increasing heart rate, dilating airways to allow for more oxygen, increasing blood pressure, inhibiting digestion, and stimulating production of adrenaline during crisis
central canal
canal that extends down length of spinal cord; contains cerebrospinal fluid
centr/o
center
cerebell/o
cerebellum
cerebr/o
cerebrum
Reye's syndrome
combination of symptoms including acute encephalopathy and damage to various organs, especially the liver; occurs in children who have had a viral infection; also associated with taking aspirin
unconscious
condition or state of being unaware of surroundings with inability to respond to stimuli
gyri
convoluted, elevated portions of cerebral cortex
The peripheral nervous system contains two sets of nerves, which include:
cranial nerves and the spinal nerves
arachnoid layer
delicate middle layer of meninges
dysphasia
difficulty communicating verbally or in writing due to damage of speech or language centers in the brain
dur/o
dura mater
syncope
fainting
myelin
fatty substance that wraps around many axons; acts as insulation so axons can conduct electrical impulses faster
ventricles
fluid-filled spaces within cerebrum; contain cerebrospinal fluid
gli/o
glue
poli/o
gray matter
the CNS contains both ______ matter and ______ matter
gray; white
ataxia
having lack of muscle coordination as a result of disorder or disease
cephalalgia
headache
aphasia
inability to communicate verbally or in writing due to damage of speech or language centers in the brain
encephalitis
inflammation of the brain
cerebellitis
inflammation of the cerebellum
tremor
involuntary, repetitive, alternating movement of a part of the body
cerebrum
largest section of brain; located in upper portion and is area that possesses thoughts, judgment, memory, association skills, and ability to discriminate between items; outer layer is called the cerebral cortex, which is composed of folds of gray matter
temporal lobe
lateral portion of the cerebrum; controls hearing and smell
focal seizure
localized seizure often affecting one limb
medull/o
medulla oblongata
mening/o, meningi/o
meninges
ment/o
mind
frontal lobe
most anterior portion of the cerebrum; controls motor function, personality, and speech
occipital lobe
most posterior portion of the cerebrum; controls vision
parietal lobe
most superior portion of the cerebrum; receives and interprets nerve impulses from sensory receptors and interprets language
-taxia
muscle coordination
monoparesis
muscle weakness of one extremity
neur/o
nerve
neuralgia
nerve pain
radicul/o
nerve root
afferent neurons
nerve that carries impulses to brain and spinal cord from skin and sense organs; also called sensory neurons
descending tracts
nerve tracts carrying motor signals down spinal cord to a peripheral nerve
ascending tracts
nerve tracts carrying sensory information up spinal cord to brain
efferent neurons
nerves that carry impulses away from brain and spinal cord to muscles and glands; also called motor neurons
somatic nerves
nerves that serve skin and skeletal muscles and are mainly involved with conscious and voluntary activities of body
quadriplegia
paralysis of all four extremities; same as tetraplegia
paraplegia
paralysis of lower portion of the body and both legs
monoplegia
paralysis of one extremity
hemiplegia
paralysis on only one side of body
anesthesia
partial or complete loss of sensation with or without loss of consciousness as a result of drug, disease, or injury
pont/o
pons
midbrain
portion of brainstem that acts as a pathway for impulses to be conducted between the brain and spinal cord
medulla oblongata
portion of brainstem that connects spinal cord with brain; contains respiratory, cardiac, and blood pressure control centers
hypothalamus
portion of diencephalon that lies just below thalamus; controls body temperature, appetite, sleep, sexual desire, and emotions such as fear; also regulates release of hormones from pituitary gland and regulates parasympathetic and sympathetic nervous systems
thalamus
portion of diencephalon; composed of gray matter and acts as center for relaying impulses from eyes, ears, and skin to cerebrum; pain perception is also controlled here
autonomic nervous system
portion of nervous system consisting of nerves to internal organs that function involuntarily; regulates functions of glands (especially salivary, gastric, and sweat glands), adrenal medulla, heart, and smooth muscle tissue; system is divided into two parts: sympathetic and parasympathetic
coma
profound unconsciousness resulting from illness or injury
spinal cord
provides pathway for impulses traveling to and from brain; column of nerve fibers that extends from medulla oblongata of brain down to level of second lumbar vertebra
clon/o
rapid contracting and relaxing
cerebellum
second largest portion of brain, located beneath posterior portion of cerebrum; this part of brain aids in coordinating voluntary body movements and maintaining balance and equilibrium; is attached to brainstem by pons; refines muscular movement that is initiated in cerebrum
esthesi/o
sensation, feeling
aura
sensations, such as seeing colors or smelling unusual odor, that occur just prior to epileptic seizure or a migraine headache
alges/o
sense of pain
convulsion
severe involuntary muscle contractions and relaxations; these have a variety of causes, such as epilepsy, fever, and toxic conditions
thec/o
sheath (meninges)
subarachnoid space
space located between arachnoid layer and pia mater; contains cerebrospinal fluid
subdural space
space located between dura mater and arachnoid layer
migraine
specific type of headache characterized by severe head pain, photophobia, vertigo, and nausea
-phasia
speech
myel/o
spinal cord
astr/o
star
semiconscious
state of being aware of surroundings and responding to stimuli only part of time
delirium
state of mental confusion with lack of orientation to time and place
seizure
sudden, uncontrollable onset of symptoms; such as in epileptic seizure
paralysis
temporary or permanent loss of function or voluntary movement
palsy
temporary or permanent loss of the ability to control movement
pia mater
term means soft mother; this thin innermost meninges layer is applied directly to the surface of the brain
dura mater
term means tough mother; it is the fibrous outermost meninges layer that forms a tough protective layer
thalam/o
thalamus
brainstem
this area of brain has three components: medulla oblongata, pons, and midbrain; it is a pathway for impulses to be conducted between brain and spinal cord; also contains centers that control respiration, heart rate, and blood pressure
pons
this portion of the brainstem forms a bridge between the cerebellum and the cerebrum
meninges
three connective tissue membrane layers that surround brain and spinal cord; three layers are dura mater, arachnoid layer, and pia mater; dura mater and arachnoid layer are separated by subdural space; arachnoid layer and pia mater are separated by subarachnoid space
tom/o
to cut
concuss/o
to shake violently
ton/o
tone
Sensory nerves carry information ____________ the central nervous system, and motor nerves carry commands _________ from the central nervous system.
toward; away
astrocytoma
tumor of brain or spinal cord composed of astrocytes
absence seizure
type of epileptic seizure that lasts only a few seconds to half a minute, characterized by loss of awareness and absence of activity; also called petit mal seizure
tonic-clonic seizure
type of severe epileptic seizure characterized by loss of consciousness and convulsions; seizure alternates between strong continuous muscle spasms (tonic) and rhythmic muscle contraction and relaxation (clonic); also called grand mal seizure
ventricul/o
ventricle
cerebrospinal fluid (CSF)
watery, clear fluid found in ventricles of brain; provides protection from shock or sudden motion to brain
-paresis
weakness
hemiparesis
weakness or loss of motion in one side of the body