Spinal Cord and Peripheral Connections Practice Flashcards

50 vocabulary flashcards covering the anatomy, protection, and functional organization of the spinal cord and spinal nerves based on the lecture transcript.

Spinal cord

The component of the central nervous system that connects primarily with the peripheral nervous system and the brain.

Spinal reflexes

A major function of the spinal cord involving connections through spinal nerves to link the periphery of the body to the central nervous system.

Integration

The process of inhibiting and creating excitatory impulses within the nervous system, which occurs even in spinal cord reflexes.

Information superhighway

A metaphor for the spinal cord's function of delivering sensory information upward to the brain and motor information downward to the body's effectors.

31 pairs

The approximate number of spinal nerves that form a network projecting off the spinal cord.

Medulla of longata

The part of the brain that connects to the spinal cord at the level of the foramen magnum.

L2

The approximate area where the spinal cord ends, though it can variably end at T12 or L1.

Cervical enlargement

A proximal landmark on the spinal cord that provides the origin of nerves for the head, neck, and upper extremities.

Lumbar enlargement

Also called the lumbosacral enlargement, it is the origin area for nerves going to the lower abdomen, groin, and lower extremities.

Conus medullaris

The V-shaped, distal aspect at the very end of the spinal cord.

Cauda equina

A network of spinal nerves extending from the conus medullaris that resembles a horse's tail.

Final terminal

An extension of connective tissue that helps to hold the distal end of the spinal cord in place.

Spinal meninges

Soft tissue membranes that wrap around the outer aspect of the spinal cord to provide protection.

Cerebrospinal fluid

A fluid contained within specific spaces that acts as a shock absorber for the spinal cord.

Intervertebral discs

Cushions between vertebrae that act as mechanical shock absorbers to withstand vertical compressive forces.

Dura mater

The outer layer of the meninges; the name translates to 'tough mother'.

Arachnoid layer

The middle layer of the meninges; the name translates to 'spider like'.

Pia mater

The inner layer of the meninges, adherent directly to the surface of the cord; the name translates to 'delicate'.

Epidural space

The space between the internal surface of the vertebrae and the dura mater, containing adipose tissue.

Subdural space

A potential space between the dura mater and the arachnoid layer that may contain a small amount of fluid.

Subarachnoid space

The most important space located between the pia mater and the arachnoid layer, containing cerebrospinal fluid.

Ependymal cells

The cells responsible for making cerebrospinal fluid.

Buoyancy

A property provided by the cerebrospinal fluid that reduces the functional weight of the brain from about three or four pounds to about two ounces.

White matter

Nervous tissue on the outer aspect of the spinal cord primarily made up of myelinated neurons.

Gray matter

Nervous tissue in the central part of the spinal cord, shaped like a butterfly, containing cell bodies and unmyelinated axons.

Horns

The three primary areas of gray matter (posterior, anterior, and lateral) that provide attachment sites for spinal nerves.

Posterior root

Also called the dorsal root, this structure receives sensory axons and attaches to the posterior gray horn.

Anterior root

The structure that attaches to the anterior gray horn, allowing motor neurons to exit the spinal cord toward skeletal muscles.

Lateral gray horn

A region of gray matter specifically for autonomic neurons, primarily those of the sympathetic nervous system.

White columns

Organized regions of white matter (dorsal, lateral, and anterior) filled with axons or tracts traveling up and down the cord.

Tract

A collection or group of axons within the central nervous system.

Nerve

A grouping of axons located outside of the central nervous system.

Ascending tracts

Tracts within the white matter that are always sensory and carry information upward to the brain.

Descending tracts

Tracts within the white matter that are always motor and carry impulses downward from the brain.

Spinocerebellar tract

A sensory tract that originates in the spine and ends in the cerebellum.

Spinothalamic tract

A sensory tract that begins in the spinal cord and ends in the thalamus.

Cortico-

A naming prefix for tracts that originates in the cerebral cortex.

Spinal- (suffix)

A naming indicator that a tract is motor, as it ends in the spinal cord.

Reflex arc

The basic structural and functional circuit of the nervous system consisting of a receptor, sensory neuron, integration center, and motor neuron.

Fascicles

Individual groups of axons within a nerve.

Epineurium

The connective tissue membrane that wraps around the outer aspect of a nerve.

Perineurium

The connective tissue membrane that wraps around a fascicle.

Endoneurium

A very thin connective tissue structure that wraps around an individual axon.

Neuritis

The swelling and buildup of fluid around neurons caused by damage to connective tissue and vessels, lead to pain.

Plexus

A functional group of spinal nerves that work together as a unit to provide innervation to a particular region of the body.

Phrenic nerve

A nerve from the cervical plexus that travels down to the diaphragm to control breathing.

Brachial plexus

A network originating from the lower cervical and upper thoracic regions that innervates the shoulder and upper extremity.

Sciatic nerve

The largest nerve in the body, originating from the sacral plexus, which innervates the hamstring and muscles below the knee.

Dermatome

An area of skin innervated by a specific or individual spinal nerve.

Referred pain

Pain that originates in an internal organ but is felt in the dermatomes of the skin, such as pain in the arm during a heart attack.