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