Lecture: Ascending Sensory Pathways I Flashcards Preview

C&M Term 2 > Lecture: Ascending Sensory Pathways I > Flashcards

Flashcards in Lecture: Ascending Sensory Pathways I Deck (17):
1

What is the Spinothalamic pathway responsible for?

Pain
Temperature
some touch

2

What is the dorsal column pathway responsible for?

Touch
Vibration
joint position (proprioception)
discriminative touch

3

Describe the type of fibres in the spinothalamic pathway

Thin
Poorly myelinated or unmyelinated
conduction slow

4

Describe the type of fibres in the dorsal column pathway

large diameter
heavily myelinated
fast conduction

5

Are the dorsal column pathway and spinothalamic pathway ipsilateral, or contralateral?

Dorsal Column - Ipsilateral, then crosses at closed medulla

Spinothalamic - contralateral, crosses at point of entry

6

To which part of the thalamus does the information carried in these pathways project?

Ventroposterolateral thalamus

7

Where does the primary neuron synapse?

With the secondary neuron in the dorsal grey horn on the same side that it enters.
Just at different levels depending on STT or DCP

8

To which part of the thalamus do sensory fibres from the face ascend?

Ventroposteromedial

9

Describe briefly how the post-central gyrus is somatotopically mapped

From lateral to medial:
Pharynx-tongue-mouth-face (ascending)-thumb-hand-along arm-trunk-down body-legs-toes-genitals

10

What is the spinothalamic pathway renamed as it enters the medulla?

The Spinal Lemniscus

11

How are the dorsal column pathways organised?

Into two pathways, the Gracile Fasciculus and the Cuneate Fasciculus
Terminate at the Gracile and Cuneate Tubercles respectively

12

Describe the Gracile Fasciculus

More medial to midline
runs whole length of the spinal cord
receives information from lower limbs and trunk

13

Describe the Cuneate Fascicle

More lateral
exist above T6 only
receives info from the arms

14

Where do the primary neurons of the Dorsal Column Pathway synapse?

In the gracile/cuneate nuclei, located in the tubercles on the dorsal brainstem

15

Describe the course of the secondary neurons in the DCP

Cross at the closed medulla
Referred to as Internal Arcuate Fibres
Pass to the Medial Lemniscus where they ascend to VPL thalamus

16

is the medial lemniscus somatotopically mapped?

Yes, divisions for Arm, Trunk and Leg

17

How do fibres travel from the thalamus to the Post central gyrus?

Via the Internal Capsule