Ojemann Lectures

Question 1

Full pathway and all information of pain/temperature sensation

Answer 1

Pain/Temperature:
Anterolateral/Spinothalamic System

C-fibers in dermatome enter innervated segment (L5 for foot) and to DRG
In dorsal horn, travel up white matter “Lissauer’s fasiculus”
Synapse at gray matter in spinal cord “Substantia gelatinosa”
Crosses midline at anterior/ventral white commissure
Ascends in anterolateral portion of spinal cord “spinothalamic tract/ALS”
Terminators at ventral posterolateral nucleus (VPL) of thalamus
Innervates somatosensory cortex

Question 2

Pain/Temperature sensation is transmitted by the ___

Answer 2

anteriolateral/spinothalamic system

Question 3

The anteriolateral/spinothalamic system transmits ___

Answer 3

pain/temperature sensation

Question 4

Steps common to the anteriolateral/spinothalamic system (pain/temperature sense) and dorsal column/medial lemniscal system (vibration/light touch/proprioception sense) are ___ and ___

Answer 4

Both ultimately terminate at ventral posterolateral nucleus (VPL) of thalamus

Both innervates somatosensory cortex

Question 5

The anteriolateral/spinothalamic tract (pain/temperature sensation) travel up white matter in the ___ called the ___

Answer 5

dorsal horn; Lissauer’s fasiculus

Question 6

The anteriolateral/spinothalamic tract (pain/temperature sensation) synapse at gray matter in the ___ called the ___

Answer 6

spinal cord; “Substantia gelatinosa”

Question 7

Which of the tracts crosses the anterior/ventral white commissure?

Answer 7

The anteriolateral/spinothalamic tract (pain/temperature sensation)

Question 8

Which of the tracts does not cross the anterior/ventral white commissure?

Answer 8

The dorsal column/medial lemniscal tract (vibration/light touch/proprioception)

Question 9

The anteriolateral/spinothalamic tract ascends in the ___ of the spinal cord

Answer 9

anterolateral portion of spinal cord “spinothalamic tract/ALS”

Question 10

Full pathway of Touch/Vibration/Proprioception below the 6th dermatome

Answer 10

Dorsal/Posterior Column/Medial Lemniscal (DC/ML) System
BELOW 6th DERMATOME:

Pacinian corpuscle (nerve ending) transduces into APs
Travels to DRG to dorsal rootlets of spinal cord
Into white matter “fasiculus gracilis”, medial
To brainstem “nucleus gracilis”
To medial lemniscus
Terminates on ventral posterolateral nucleus (VPL) of thalamus
Innervates somatosensory cortex

Question 11

The difference between the dorsal column/medial lemniscal system (light touch/vibration/proprioception) above and below the T6 dermatome is:

Answer 11

Below the 6th dermatome it travels up the spinal white matter fasciculus gracilis to the brainstem’s nucleus gracilis, MEDIAL

Above the 6th dermatome, it travels up the spinal white matter fasciulus cuneatus to the brainstem’s nucleus cuneatus, LATERAL

Question 12

The dorsal column/medial lemniscal (light touch/vibration/proprioception) system below the T6 dermatome travels up the spinal cord ____, on the medial side

Answer 12

fasciculus gracilis

Question 13

The dorsal column/medial lemniscal system (light touch/vibration/proprioception) below the T6 dermatome synapses at part of the ___ called the ___, on the medial side

Answer 13

brainstem; nucleus gracilis

Question 14

Full pathway of Touch/Vibration/Proprioception above the T6 dermatome is:

Answer 14

Dorsal/Posterior Column/Medial Lemniscal (DC/ML) System
ABOVE 6th DERMATOME:

Pacinian corpuscle (nerve ending) transduces into Aps
Travels to DRG to dorsal rootlets of spinal cord
Into white matter “fasiculus cuneatus”, lateral
To brainstem “nucleus cuneatus”
To medial lemniscus
Terminates on ventral posterolateral nucleus (VPL) of thalamus
Innervates somatosensory cortex

Question 15

The dorsal column/medial lemniscal (light touch/vibration/proprioception) system above the T6 dermatome travels up the spinal cord ____, on the lateral side

Answer 15

fasciculus cuneatus

Question 16

The dorsal column/medial lemniscal (light touch/vibration/proprioception) system above the T6 dermatome synapses at part of the ___ called the ___, on the lateral side

Answer 16

brainstem; nucleus cuneatus

Question 17

The anterior corticospinal tract controls ___

Answer 17

core musculature, ipsilaterally and contralaterally

Question 18

The core musculature, ipsilaterally and contralaterally, are controlled by ___

Answer 18

anterior corticospinal tract

Question 19

Brown-Sequard syndrome is due to ___

Answer 19

ALS/Spinothalamic tract crosses midline; DC/ML system does not – a lesion will cause contralateral pain/temperature sensation loss and ipsilateral touch/vibration/proprioception sensation loss – dissociated sensory loss

Question 20

Which of the tracts crosses the midline? What sensation does it transmit?

Answer 20

ALS/Spinothalamic tract crosses midline; DC/ML system does not – a lesion will cause contralateral pain/temperature sensation loss and ipsilateral touch/vibration/proprioception sensation loss – dissociated sensory loss

Brown-Sequard syndrome

Question 21

The lateral corticospinal tract controls ___

Answer 21

ipsilateral voluntary movement of skeletal muscle – connects upper motor neurons to lower motor neurons

Question 22

Ipsilateral voluntary movement of skeletal muscle is controlled by ___

Answer 22

lateral corticospinal tract