Anatomy - CNS - Spine

Question 1

What is the name given to white and grey matter in the spinal cord?

How can grey matter be used to orientate yourself with the spinal cord?

Answer 1

White matter = columns
Grey matter = horns

The posterior horn goes right to the edge of the spinal cord unlike the anterior horn

Question 2

At what point does the spinal cord typically start/end in the vertebral canal?

Answer 2

Foramen magnum - C1

VERTEBRAL LEVEL - L1/2

Question 3

What covers the spinal cord?

Answer 3

Meninges

- same as the ones that are present in the cranial cavity

Question 4

What is the name of the tapered cone-shape at the end of the spinal cord?

What is the name of the thin connective tissue cord that continues on from this?

Answer 4

Conus medullaris

Filum terminale

Question 5

Three major longitudinal arteries supply the spinal cord. Is it anterior or posterior that you find 2 instead of 1?

What are the other 2 sources of blood supply?

Answer 5

Posterior = 2

Segmental arteries
Radicular arteries

Question 6

What is the epidural space?

How is this useful clinically?

Answer 6

Space between the dura and bone which contains adipose tissue and the anterior and posterior epidural venous plexuses.

Used in epidural anaesethesia

Question 7

Where in the brain is sensory information processed?

Answer 7

Primary somatosensory cortex on the postcentral gyrus in the parietal lobe

Genitals and toes and processed closer to longitudinal sulcus (centre of brain) and face etc. more on edge

Question 8

Describe the relationship between amount of white matter found in the spinal cord and its position in the spinal cord.

Answer 8

As you descend white matter decreases as that section of the spine is supplying less of the body

Question 9

What are the 2 major ascending tracts?

Answer 9

Dorsal column - fine touch and conscious proprioception

Spinothalmaic tract - pain, temperature and deep pressure

Question 10

Where does the dorsal column join to in the brain?

Answer 10

Medial lemniscus

Question 11

Describe the pathway of fine touch information from the big toe

Answer 11

Big toe
Dorsal column of spinal cord
Nucleus in the medulla - SYNAPSE 
Thalamus - SYNPASE
Primary somatosensory cortex

Question 12

What is the main function of the thalamus in sensory pathways?

Answer 12

Receives sensory information and sends it to the appropriate part of the cerebral cortex

Question 13

How many neurons to reach the primary somatosensory cortex?

Answer 13

3

Question 14

Where is the first synapse in the spinothalamic tract?

Answer 14

Within the spinal cord - OPPOSITE anterolateral part of white matter

Question 15

Where in the brain is the primary motor cortex?

Answer 15

Precentral gyrus in the frontal lobe

Question 16

What is the important descending tract to know?

Answer 16

Corticospinal tract (AKA pyramidal tract)

• lateral
• medial

Question 17

Where do most of the motor tracts change sides?

Answer 17

Medulla

Question 18

Match the following descending tracts and their function:

Tectospinal
Reticulospinal
Vestibulospinal

Influencing voluntary movement
Mediate reflex head and neck movement due to visual stimuli
Stops you from falling over

Answer 18

Tectospinal - Mediate reflex head and neck movement due to visual stimuli

Reticulospinal - influencing voluntary movement

Vestibulospinal - stops you falling over

Question 19

What is found in the central canal of the spinal cord?

Answer 19

CSF