Ascending Sensory Pathways Flashcards Preview

Spot Test 2- Lower Limb > Ascending Sensory Pathways > Flashcards

Flashcards in Ascending Sensory Pathways Deck (24):
1

Somaesthetic modalities essential for survival

Conduction speed/what type of fibres

Pain, Temperature, Touch, some pressure

Thin, Poorly Myelinated Fibres

Slow Conduction

2

Somaesthetic Modalities that increase detail

Conduction speed/what type of fibres

2 Point Discrimination and vibration, Proprioception

Fat, heavily myelinated fibres

Fast conduction

3

Somaesthetic modalities carried in Spinothalamic Pathway

Pain, Temperature, Touch, some pressure

4

Somaesthetic modalities carried in Dorsal Column Pathway

2 Point Discrimination and vibration, Proprioception

5

Primary Neuron in sensory chain

Sensory Receptor to Ipsilateral CNS

6

Secondary Neuron in sensory chain

Ipsilateral CNS to Contralateral Thalamus

This neurone always responsible for decussating the SC- where this occurs depends on the pathway

7

Tertiary Neuron in sensory chain

Thalamus to Post-Central Gyrus via the Posterior limb of Internal Capsule

8

Modifications of neurons in pathway

Other inputs
1:Many or Many:1 depending on nature of information

9

At which level does the Secondary Neuron cross the midline in the Spinothalamic Pathway

Level of Entry into SC (via Ventral White Commissure)

10

Where does the Spinothalamic Tract become known as the Spinal (Lateral) Lemniscus

Medulla

11

Somatotopic Mapping of the Spinothalamic Tract?

Arm Ventrally
Trunk Medial
Leg Dorsally

12

Which nuclei does Sensory from Legs go to in the Thalamus?

Lateral VPL Nucleus

(Legs are Lateral)

13

Which nuclei does Sensory from Arms go to in the Thalamus?

Medial VPL Nucleus

14

Which nuclei does Sensory from the Face go to in the Thalamus?

VPM Nucleus

15

Where in the Cortex does the Lateral VPL Nucleus ( sensory from legs) project?

Medial Primary Motor Somatosensory Cortex

(within great longitudinal fissure)

16

Where in the Cortex does the Medial VPL Nucleus (sensory from arms) project?

Mid- Lateral Primary Somatosensory Cortex

(between legs and face mapping)

17

Where in the Cortex does the VPM Nucleus (sensory from face) project?

Lateral Primary Somatosensory Cortex

18

Where does the Primary Neuron in the Dorsal Column Pathway run?

Gracile or Cuneate Tubercles to Gracile and Cuneate Fascicles

19

Above which vertebral level is the Gracile Tubercle present?

T6

20

Where does the Gracile Tubercle carry sensory information from?

Lower Trunk, Lower Limb

21

Where does the Cuneate Tubercle carry sensory information from?

Upper Trunk, Upper Limb

22

Where are the Gracile/Cuneate Fascicles (Nuclei) located?

Closed Medulla

23

How does the Secondary neurone in the Dorsal Column Pathway travel to the Thalamus?

Crosses the midline in closed Medulla as Internal Arcuate Fibres

Travels to Thalamus in Medial Lemniscus

24

Somatotopic mapping of the Medial Lemniscus?

Legs Ventral (Just below Pyramids)
Trunk Medial
Arm Dorsal