Chapter 6: Nervous System Terminology

Medical Terminology

What is the nervous system?

The nervous system includes the brain, spinal cord, and peripheral nerves that send information in the form of neural impulses back and forth between the brain and body.

What is the purpose of the nervous system?

The nervous system serves as a command center which controls and monitors all the body's functions and activities. The brain sends and receives nerve impulses, which are transported via the spinal cord and peripheral nerves to and from the body.

alges

sensitivity to pain

-asthenia

weakness

astro

star

-cele

hernia

cephal(o)

head

cerebrum

brain

crani

skull

di-

across

-ectomy

removal

encephal(o

inside the head

gli

glue

mening

membrane

mono

single; one

myel(o)

spinal cord

neur(o)

nerve

para

beside

polio

gray

psych

mind

ventriculo

cavity in an organ

Central Nervous System

includes the brain and spinal cord

Peripheral Nervous System

includes all the peripheral nerves

neurons

the main cells of the nervous system also called nerve cells

glial cells

groups of support cells

nerve impulses

electrical signals that begin from stimulus

cell body

large round nucleus

dendrites

shorter extension of the neurons cytoplasm that receives signals

axon

extension of a neurons cytoplasm which sends nerve impulses away from the soma

receptors

proteins embedded in the membrane

stimuli

things that elicit a reaction. Can be external or internal. Ex chemicals, lights etc

myelin

Axons may be covered in a fatty insulating material; which helps with nerve impulse speed

cerebrum

forms the bulk of the brain and contains five major lobes

cerebellum

muscle coordination

diencephalon

located in the center of the brain, above the brain stem

Brain stem

connects the cerebrum to the spinal cord

fissure

A large, deep groove

sulcus

a smaller, more shallow groove

convolutions or gyri

ridges on the brain

meninges

Covering the surface features is a protective covering of the brain and spinal cord

dura mater

tough outer layer of meninges

arachnoid mater

layer of meninges attached to the underside of the dura mater

pia mater

layer of meninges attached to the surface of the brain

subarachnoid space

space between the arachnoid mater and pia mater

cerebrospinal fluid

clear, viscous the surrounds and fills the brain and spinal cord

ventricles

Within the brain and brain stem are  several fluid filled cavities

nerve

bundle of axons that relay nerve impulses to or from the brain, up or down the spinal cord, to or from the body

Peripheral nerves

nerves that are outside of the brain and spinal cord; send nerve signals from the body parts to the spinal cord or from the spinal cord to the body parts

soma

cell body of a neuron that contains the nucleus and many cellular organelles

Sensory neurons

send nerve impulses from the body parts to the brain and spinal cord

interneurons

send nerve impulses between the brain and spinal cord

motor neurons

send signals from the brain and spinal cord to the muscles or glands

CNS Glial Cells

astrocytes, microglia, ependymal cells, oligodendrocytes

PNS Glial Cells

satellite cells, Schwann cells

astrocytes

star shaped cell that helps with brain homeostasis

microglia

glial cell that supports and protects neurons

ependymal cells

cells that line the ventricles of the brain

oligodendrocytes

branching cells that produces myelin

satellite cells

surround and support soma of PNS neurons

Schwann cells

cells that produce myelin

afferent (sensory) nerves

nerves that send signals to the brain and spinal cord

autonomic nervous system

branch of the peripheral nervous system that controls unconscious functions

effector

body part or structure that is activated in response to a series of nerve impulses

efferent (motor) nerves

nerves that send signals away from the brain and spinal cord, usually to the muscles

flexure

turn or bend in the body

ganglion (ganglia)

groups of soma located outside the CNS

gray matter

tissue in the brain and spinal cord that is primarily composed of soma and dendrites

neurotransmitter

chemical released by a neuron to allow communication between cells

plexus

a collection of interconnecting nerves

reflex

involuntary response to a stimulus

sensation

when a stimulus is interpreted by the brain

somatic nervous system

a division of the peripheral nervous system that controls skeletal muscles

sympathetic nervous system

branch of the autonomic nervous system that is activated in times of stress or excitement

synapse

junction where a neuron passes its nerve impulse to another neuron or cell

white matter

tissue in the brain and spinal cord that is primarily composed of myelinated axons

aphasia

disorder that prevents speaking or understanding what is spoken

demyelination

loss of myelin

electroencephalogram

machine that records the electrical activity of the brain

encephalitis

brain inflammation

epidural

above the dura mater

glioblastoma

tumor originating from the glial cells

hydrocephalus

build-up of fluid on the brain

meningitis

inflammation of the meninges

multiple sclerosis

autoimmune disease that causes scarring of the nerves of the brain and spinal cord

neuralgia

pain along a nerve pathway

neurologist

a medical specialist that diagnoses and treats nervous system disorders

neurology

study of the nervous system

neuroma

tumor on a nerve

neuropathy

condition because of damage to the nerves

poliomyelitis

inflammation of the gray matter of the spinal cord

subdural hematoma

buildup of blood under the dura mater of the brain