Ascending Sensory pathways 2

Question 1

What cranial nerves carry general sensation from the head? And in which pathway does the info from these nerves run?

Answer 1

V (trigeminal)
VII (facial)
IX (glossopharyngeal)
X (vagus)

Run in the trigeminal sensory pathway

Question 2

What part of the Trigeminal nucleus recieves pain and temperature info?

Answer 2

Caudal part of spinal nucleus

Question 3

What part of the trigeminal nucleus recieves simple touch and pressure info?

Answer 3

Rostral part of spinal nucleus

Question 4

What info is recieved by the spinal nucleus?

Answer 4

Caudal = pain and temp
Rostral = touch and pressure

Question 5

Where does the cell body of primary neurons carrying pain,temp, touch and pressure sensation from the face lie? Also where does it synapse with the secondary neuron?

Answer 5

cell body lies in the trigeminal ganglion.

Synapses in the Spinal nucleus.

(pain/temp in the caudal region. touch/pressure in the rostral region)

Question 6

Where in the thalamus does pain, temp , touch and pressure info go?

Answer 6

VPM

Question 7

What effect will a lesion affecting the lateral medulla have on sensation from the face?

Answer 7

Pain, temp, touch and pressure from the face will not be felt. (spinal nucleus)

However discriminative touch (pontine nucleus) and proprioception (mesencephalic nucleus) will be felt.

Question 8

What affect will a lesion affecting the lateral medulla have on sensation from the body?

Answer 8

Spinothalamic sensation (pain, temp ) will be affected as the tract lies laterally.

However (depending on size of lesion) dorsal column pathway (discriminatory touch and proprioception) from body not affected as it runs in cuneate/gracile fascicles and crosses over via arcuate fibres.

Question 9

What part of the trigeminal sensory nucleus recieves discriminatory touch sensation from the face?

Answer 9

Pontine

Question 10

What part of the trigeminal sensory nucleus recieves proprioception?

Answer 10

Mesencephalic nucleus

Question 11

where does the primary neuron cell body carrying discriminatory touch to the pontine nucleus lie? and where does it synapse?

Answer 11

trigeminal ganglion = primary cell body

synapses in the pontine nucleus

Question 12

Where does the cell body of the nerve carrying proprioception info lie?

Answer 12

Mesencephalic nucleus

Question 13

Where doe the neuron carrying proprioception from the face synapse/

Answer 13

1) just outside mesencephalic nucleus
2) synapse with motor neurons in the trigeminal motor nucleus. These motor neurones go on to supply muscles of mastication.