Ascending Tracts

Question 1

Conscious tracts

Answer 1

DCML pathway

Anterolateral system

Question 2

Unconscious tracts

Answer 2

Spinocerebellar tracts

Question 3

DCML carries what sensory modalities?

Answer 3

Fine touch
Vibration
Proprioception

Question 4

How many neurones are involved in the DCML?

Answer 4

3

Question 5

First order neurones carrysensory information to where?

Answer 5

Medulla oblongata

Question 6

Signals from the lower limb are carried in what specific part of the DCML?

Answer 6

fasciculus gracilis

Question 7

Signals in the fasciculus gracilis synapse onto what?

Answer 7

gracile nucleus of the medulla oblongata

Question 8

Signals from the upper limb are carried in what specific part of the DCML?

Answer 8

Fasiciulus cuneatus

Question 9

Signals in the fasciculus gracilis synapse onto what?

Answer 9

Cuneate nucleus of the medulla oblongata

Question 10

What happens to the fibres of the DCML pathway in the medulla?

Answer 10

They decussate

Question 11

Second order neurones travel in the what relative to the side of initial sensory input to where?

Answer 11

Contralateral medial lemniscus to the thalamus

Question 12

Third order neurones take the signals where in the DCML?

Answer 12

From the ventral posterolateral nucleus of the thalamus to the primary sensory cortex (post-central gyrus)

Question 13

What modalities does the anterior spinothalmaic tract carry?

Answer 13

crude touch and pressure

Question 14

What modalities does the lateral spinothalmaic tract carry?

Answer 14

pain and temperature

Question 15

The anterior and lateral spinothalamic tracts make up what?

Answer 15

The anterolateral system

Question 16

How many neurones are involved in the anterolateral system?

Answer 16

3

Question 17

What happens to first order neurones of the anterolateral system?

Answer 17

Arise from the sensory receptors in the periphery. They enter the spinal cord, ascend 1-2 levels, and terminate at the tip of the dorsal horn (the substantia gelatinosa).

Question 18

Second order neuroes of the anterolateral system carry information from the substantia gelatinosa to the what?

Answer 18

Thalamus

Question 19

What happens to the second order neurones of the anterolateral system after it synapses at the substantia gelatinosa?

Answer 19

It decussates and anterior and lateral spinothalamic tracts split functionally but run alongside each other

Question 20

Where do third order neurones of the anterolateral system, ascend from towards the primary sensory cortex?

Answer 20

Ascend from teh ventral posterolateral nucleus of the thalamus, through the internal capsule, terminating at the sensry cortex

Question 21

The spinocerebellar tracts do what?

Answer 21

Transmit unconscious proprioceptive information from the muscles to the cerebellum.