Spinal Cord/tracts

Front 1

spinal meninges

Back 1

dura matar, arachnoid, pia mater.

Front 2

spinal dura mater

Back 2

only one layer; outermost of the three spinal meninges; tough and fibrous

Front 3

arachnoid mater

Back 3

middle spinal meninge

Front 4

pia mater

Back 4

innermost spinal meninge; adheres to surface of spinal cord

Front 5

Location of spinal cord in reference to vertebrae

Back 5

Foramen magnum in base of skull to L1/L2

Front 6

Spinal cord enlargements

Back 6

cervical and lumbar

Front 7

conus medullaris

Back 7

point where spinal cord ends; cone-shaped terminal portion

Front 8

filum terminal

Back 8

extends from conus medullaris (end of spinal cord) to saccrum; fibrous connctive tissue that anchors spinal cord to coccyx bone.

Front 9

cauda equina

Back 9

"horse's tail"; the caudal extension of filum terminal along with long ventral and dorsal roots of the spinal cord which extend to the lower extremities and trunk.

Front 10

anterior median fissure

Back 10

deep crease along ventral surface of the spinal cord

Front 11

posterior median sulcus

Back 11

shallow longitudinal groove on dorsal surface of the spinal cord (spine side, not very obvious)

Front 12

3 somatosensory tracts

Back 12

Dorsal Column Pathway
Lateral Spinothalamic Pathway
Dorsal Spinocerebellar Pathway

Front 13

fasciculus gracilis

Back 13

dorsal column spinal tract from lower extremities and trunk to nucleus gracilis in medulla

Front 14

fasciculus cuneatus

Back 14

dorsal column spinal tract from upper limbs/trunk to nucleus cuneatus in medulla

Front 15

Dorsal Column Pathway: what it conveys

Back 15

touch, pressure, tactile discrimination and joint movement (proprioceptive); position of a joint in space, during movement.

Front 16

Dorsal Column Pathway

Back 16

1. Sense perception in extremity or trunk enters spinal cord via dorsal root, enters gracilis or cuneatus.
2. Impulse runs up Dorsal Spinal column tract to medulla oblongata to synapse with 2nd neuron in nucleus gracilis/cuneatus.
3. 2nd neuron exits medulla via medial lemniscus pathway during which the tract crosses over to the contralateral side, then synapse on 3rd neuron in Ventral PosteroLateral nucleus of Thalamus.
4. VPL 3rd neuron projects to layer 4 of the somatosensory cortex in the postcentral gyrus of the cerebellar neocortex.

Front 17

What Lateral Spinothalamic tract conveys

Back 17

Pain and Temperature

Front 18

Lateral Spinothalamic tract

Back 18

1. Sensory info enters dorsal root of spinal cord, immediately crosses to contralateral side to synapse with 2nd neuron in dorsal horn of that side.
2. Impulse continues up lateral Spinothalamic tract to thalamus to synapse with 3rd neuron.
3. 3rd neuron in thalamus projects to layer 4 in primary sensory cortex in cerebral postcentral gyrus

Front 19

What info Dorsal Spinocerebellar Tract conveys

Back 19

proprioceptive info about joint position in space to the cerebellum, so that it can immediately and continuously be sending corrective info to the motor pathway so that limb stays on target with high fidelity

Front 20

dorsal spinocerebellar tract pathway

Back 20

1. Sensory info enters dorsal root into spinal cord.
2. Immediately curves to the dorsal horn of the SAME side (ipsilateral) and shoots to cerebellum.
2-neuron pathway; no crossover.

Front 21

What Lateral Corticospinal Tract conveys

Back 21

Motor impulses for conscious skeletal muscle movement. According to the cortical lamination pattern, pyramidal cells project from layer 5 of the primary motor cortex, precentral gyrus.

Front 22

Lateral Corticospinal Tract Pathway

Back 22

1. Motor impulse conveyed from internal pyramidal layer of primary motor cortex through the midbrain via anterior cerebral peduncles to the pyramidal decussation in the medulla where impulse crosses to contralateral side. Then (still 1st neuron) continues down spinal cord to level of regional innervation.
2. Synapse of 1st neuron to 2nd in ventral horn of vertebra, then out ventral horn to skeletal muscle.