Central Nervous System: The Spinal Cord

Front 1

Epidural Space

Back 1

Is found between the bony vertebrae and the spinal dura mater, filled with a soft padding of fat and a network of veins.

Front 2

Spinal Dura Mater

Back 2

The outer most protective layer of the meninges pertaining to the spinal cord.

Front 3

Subarachnoid Space

Back 3

Space between the arachnoid and pia mater meninges filled with cerebrospinal fluid.

Front 4

The spinal cord typically ends between...

Back 4

L1 and L2

Front 5

Conus Medullaris

Back 5

A tapering cone-shaped structure inferior to the spinal cord terminal.

Front 6

Filum Terminale

Back 6

A fibrous extension of the conus covered by pia mater, extends inferiorly from the conus medullaris to the coccyx, where it anchors the spinal cord so it's not jostled by body movement.

Front 7

Denticulate Ligaments

Back 7

Saw-toothed shelves of pia mater that secure the spinal cord to the tough dura mater meninx throughout its length.

Front 8

Cervical Enlargement

Back 8

Enlargement where the nerves serving the upper limbs arise.

Front 9

Lumbar Enlargement

Back 9

Enlargement where the nerves serving the lower limbs arise.

Front 10

Cauda Equina

Back 10

Collection of nerve roots at the inferior end of the vertebral canal which resembles a horse's tail.

Front 11

Ventral (Anterior) Median Fissure

Back 11

A wide groove which marks the frontal surface of the spinal cord throughout its length and partially divides it into right and left half.

Front 12

Dorsal (Posterior) Median Sulcus

Back 12

A narrow groove which marks the surface of the spinal cord throughout its length and partially divides it into right and left half.

Front 13

Central Canal

Back 13

At the core of the spinal cord, this cerebrospinal fluid filled tunnel, runs the length of the spinal cord.

Front 14

Gray Commisure

Back 14

A crossbar of gray matter connecting the lateral gray masses and encloses the central canal.

Front 15

Dorsal (Posterior) Horns

Back 15

Two horn-like dorsal projections of the gray matter.

Front 16

Ventral (Anterior) Horns

Back 16

A pair of ventral projections of the gray matter which consist of somatic motor neurons.

Front 17

Lateral Horns

Back 17

Columns located in the thoracic and superior lumbar segments of the spinal cord and is the gray matter projection between the ventral and dorsal horn, which consist of mostly autonomic motor neurons.

Front 18

Ventral Roots

Back 18

Contain somatic motor neuron axons that signal the skeletal muscles (their effector organs) and automatic motor neuron axons that signal the visceral organs, serving both motor divisions of the PNS.

Front 19

Dorsal Roots

Back 19

Afferent fibers carrying impulses from the peripheral sensory receptors.

Front 20

Dorsal Root Ganglion

Back 20

Enlarged region of the dorsal root that contains the cell bodies of the associated sensory neurons.

Front 21

Four Zones of the Spinal Gray Matter

Back 21

From Posterior to Anterior:

Somatic Sensory (SS)

Visceral Sensory (VS)

Visceral (Automatic) Motor (VM)

Somatic Motor (SM)

Front 22

White Matter: Three Directions of Fiber

Back 22

Ascending

Descending

Transverse

Front 23

Ascending Fibers of White Matter

Back 23

Sends sensory inputs up to higher centers.

Front 24

Descending Fibers of White Matter

Back 24

Sends motor outputs down to the cord from the brain or within the cord to lower levels.

Front 25

Tranverse Fibers of White Matter

Back 25

Commisural fibers running across from one side of the cord to the other.

Front 26

What is the name of the three divisions of the spinal cord's white matter?

Back 26

White Columns or Funiculi

Front 27

Three Divisions of White Columns/Funiculi

Back 27

Dorsal (Posterior) Funiculi

Lateral Funiculi

Ventral (Anterior) Funiculi

Front 28

Pathway Generalization: Four Key Points in Regards to Spinal Tracts and Pathways

Back 28

Decussation

Relay

Somatotopy

Symmetry

Front 29

Decussation

Back 29

Pathways of nerve fibers crossing from one side of the CNS to the other (decussate).

Front 30

Relay

Back 30

Pathways consist of a chain of two or three neurons (a relay) that contribute to successive tracts of the pathway.

Front 31

Somatotopy

Back 31

Pathways exhibiting a precise spatial relationship among the tract fibers that reflects the orderly mapping of the body.

Front 32

Symmetry

Back 32

All pathways and tracts are paired symmetrically (right and left), with a member of the pair present on each side of the spinal cord or brain.