[ANAT] DORSAL COLUMN TRACTS

Question 1

function of dorsal column tracts

Answer 1

carry proprioception

Question 2

tracts of dorsal column

Answer 2

cuneate (above T6)
gracile (below T6)

Question 3

beginning of dorsal column tracts

Answer 3

central processes of pseudounipolar dorsal root ganglion

Question 4

position of tracts

Answer 4

gracile=lies medially
cuneate=lies laterally

Question 5

tracts occupy

Answer 5

posterior white column

Question 6

lamination

Answer 6

coccygeal & sacral fibers=most medially
cervical=most laterally

Question 7

termination of tracts

Answer 7

gracile & cuneate nuclei in medulla

Question 8

collateral branches of gracile & cuneate tracts end on

Answer 8

dorsal horn of spinal cord

Question 9

sensations carried by Dorsal column tracts (5)

Answer 9

1-fine touch
2-proprioception
3-vibration
4-pressure
5-stereognosis

Question 10

first neuron

Answer 10

dorsal root ganglion cells

Question 11

function of peripheral processes of dorsal root ganglion cells

Answer 11

carry sensations from deep receptors

Question 12

collaterals of gracile & cuneate tracts

Answer 12

septo-marginal tract (G)
comma shaped tract (C)

Question 13

second neuron

Answer 13

gracile & cuneate nuclei

Question 14

third order neuron

Answer 14

(VPLN) ventral posterolateral nucleus of thalamus

Question 15

path of axons of 3rd order neuron

Answer 15

posterior limb of internal capsule–>corona radiata—>sensory cortex

Question 16

path of axons of 2nd order neuron

Answer 16

1- cross median plane
2- form internal arcuate fibers (sensory decussation)
3- ascend brain stem as medial lemniscus
4- reach thalamus

Question 17

axons of which fibers pass to cerebellum

Answer 17

cuneo-cerebellar fibers

Question 18

some cervical fibers end on ___

Answer 18

accessory cuneate nucleus