Med Terms Nervous System

Central Nervous system (CNS)

brain and spinal cord

peripheral nervous system (PNS)

12 pairs of cranial nerves extending from brain and 31 pairs of peripheral spinal nerves extending outward from the spinal cord, transmits nerve signals to and from cns

ascending nerve tracts

toward brain

descending nerve tracts

away from brain

tract

bundle or group of nerve fibers

nerve

one or more bundles of neurons

ganglion

nerve center made up of a cluster of nerve cell bodies outside cns

innervation

supply of nerves to specific body part

plexus

network of intersecting spinal nerves

receptors

sites in sensory organs and taste buds that receive external stimulation

impulse

wave of excitation transmitted through nerve fibers and neurons

brain waves

patterns of neuron electrical activity

dendrites

root like processes that receive impulses and conduct them to cell body

process

structure that extends out from the cell body

axon

process that conducts impulses away from the nerve cell

terminal end fibers

branching fibers at end of axon that lead to nerve impulse from axon to synapse

synapse

space between 2 neurons or between a neuron and a receptor organ

neurotransmitters

chemical substances that make it possible for messages to cross from the synapse of a neuron to the target receptor

acetylcholine

released at some synapses in the spinal cord and at neuromuscular junctions; it influences muscle action

dopamine

released within the brain and plays a role in motivation, pleasure, and muscle movement

endorphines

naturally occurring substances produced in brain to help relive pain

norepinerphrine

affects alertness and arousal, increasing blood pressure and heart rate, and releasing stores of glucose in response to stress, fight or flight

serotonin

released in the brain, has roles in sleep, hunger, and pleasure recognition

glial cells

provide support and protection for neurons. They surround neurons and hold them in place, supply nutrients and oxygen, insulation one neuron from another, destroy and remove dead neurons

myelin sheath

protective covering made up of glial cells, forms the white matter of the brain and covers some parts of the spinal cord and the axon of most peripheral nerves

white matter

portion of nerve fibers that are myelinated

grey matter

unmyelinated

meninges

membranes that enclose brain and spinal cord

dura mater

thick, tough, outermost membrane of the meninges

mater

mother

epidural space

inner surface of vertebral column

subdural space

between dura mater and arachnoid membrane

arachnoid membrane

resembles a spider web, is the second layer of meninges and is located between dura mater and pia mater

arachnoid

spider

subarachnoid space

located below arachnoid membrane and above pia mater, contains cerebrospinal fluid

pia mater

third layer of the meninges, is located nearest to the brain and spinal cord. consists of delicate connective tissue that contains a rich supply of blood vessels

pia

tender or delicate

cerebrospinal fluid, spinal fluid

produced by special capillaries within the four ventricles located in the middle region of the cerebrum. cools and cushions organs from shock or injury and nourishes brain and spinal cord by transporting nutrients and chemical messengers to these tissues

cerebrum

largest and uppermost part of brain, consists of 4 lobes

thalamus

located below cerebrum, relays sensory stimuli from the spinal cord and midbrain to the cerebral cortex

cerebellum

part of brain responsible for smooth, coordinated movements

brainstem

responsible for critical survival (breathing/heart rate)

sympathetic nerves

fight or flight

parasympathetic nerves

ordinary circumstances, rest and digest

peripheral spinal nerves

transmit signals to and from cns

cerebral cortex

made of grey matter, outer layer of cerebrum

gyri

elevated folds of grey matter in cerebral cortex

sulci

fissures of cerebral cortex

fissure

normally occurring deep grove

corpus callosum

connects cerebral hemispheres at lower midpoint

left cerebral hemisphere

controls function on right side of body

right cerebral hemisphere

controls function of left side of body

frontal lobe

skilled motor functions, memory and behavior

parietal lobe

receives and interprets nerve impulses from sensory receptors in the tongue, skin, muscles

occipital lobe

eyesight

temporal lobe

controls hearing and smell, and ability to create, store, and access new info

hypothalamus

located below thalamus, Regulates and integrates the autonomic nervous system, including controlling heart rate, blood pressure, respiratory rate, and digestive tract activity, Regulates emotional responses, including fear and pleasure, Regulates body temperature, Regulates food intake by controlling hunger sensations, Regulates water balance by controlling thirst sensations, Regulates sleep–wakefulness cycles, Regulates the pituitary gland and endocrine system activity

midbrain and pons

conduction pathways to and from higher and lower centers in the brain, control reflexes for movement of eyes and head in response to visual and auditory stimuli

medulla oblongata

located at lowest part of brainstem, connected to spinal cord. Controls basic survival functions

peripheral

pertaining to body parts that are away from center of body

autonomic nerve fibers

carry instructions to the organs and glands from the autonomic nervous system

sensory nerve fibers

receive external stimuli, such as how something feels, and transmit this information to the brain where it is interpreted

somatic nerve fibers, motor nerve fibers

convey information that controls the body’s voluntary muscular movements

autonomic nerves

2 divisions - sympathetic nerves and parasympathetic nerves

anesthesiologist

physician

anesthetist

not a physician

psychiatrist

physician, can prescribe meds

psychologist

phd or psyd but not md

cephalgia

headache

migraine headache

characterized by throbbing pain on one side of the head

warning aura

visual disturbance perceived by the patient preceding a migraine headache or epileptic seizure.

cluster headache

intensely painful headaches that affect one side of the head and may be associated with tearing of the eyes and nasal congestion

encephalocele, craniocele

a congenital herniation of brain tissue through a gap in the skull

cele

hernia

herniation

protrusion of a structure from its normal position

meningocele

congenital herniation of the meninges through a defect in the skull or spinal column

hydrocephalus

condition in which excess cerebrospinal fluid accumulates in the ventricles of the brain

meningitis, infections meningitis

inflammation of the meninges of the brain and spinal cord, can be caused by a bacterial or viral infection elsewhere in the body, is characterized by intense headache and flu-like symptoms.

chiari malformation

congenital condition in which part of the cerebellum extends down into the spinal canal.

encephalitis

inflammation of the brain, can be caused by a viral infection such as rabies

reye’s syndrome

serious and potentially deadly disorder in children that is characterized by vomiting and confusion, sometimes follows a viral illness in which the child was treated with aspirin

tetanus, lockjaw

cute and potentially fatal infection of the central nervous system caused by a toxin produced by the tetanus bacteria

Tourette syndrome

complex neurological disorder characterized by involuntary tics, grunts, and compulsive utterances that sometimes include obscenities.

cognition

mental activities associated with thinking, learning, and memory

dementia

slowly progressive decline in mental abilities, including memory, thinking, and judgment, that is often accompanied by personality changes

senile demetia

dementia of the aged

vascular dementia

dementia caused by a stroke or other restriction of the flow of blood to the brain.

Alzheimer’s disease

group of disorders involving the parts of the brain that control thought, memory, and language, leading form of dementia

Huntington’s disease

genetic disorder classified as a neurodegenerative disease

parkinson’s disease

chronic, degenerative central nervous disorder characterized by fine muscle tremors, rigidity, and a slow or shuffling gait

parkinsonian tremor

pill rolling movement of hands while at rest

essential tremor

shakiness of the arms, hands, or head, which worsens during voluntary movements

lewy body dementia

second most common type of dementia, occurs when abnormal proteins interfere with cell function in the brain. It is named for neurologist Frederic Lewy.

amyotrophic lateral sclerosis (als), lou gehrig’s disease

rapidly progressive neurological disease that attacks the nerve cells responsible for controlling voluntary muscles. Patients affected with this condition become progressively weaker until they are completely paralyzed and die.

amnesia

memory disturbance characterized by a total or partial inability to recall past experiences

concuss

shaken together

epidural hematoma

above dura mater

subdural hematoma

below dura mater

coup

injury occurring within the skull near the point of impact

contrecoup, counter blow

injury that occurs beneath the skull opposite to the area of impact