Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Theme 1: Neuro Anatomy > Structure and function of the spinal cord > Flashcards

Structure and function of the spinal cord Flashcards

1
Q

Anatomy of the spinal cord

A

Sits within vertebral column- well protected

Surrounded by meninges

Divided into 4 regions

  • cervical (C1-8)
  • thoracic (T1-12)
  • lumbar (L1-5)
  • sacral (S1-5)
  • lumbar cistern
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Spinal nerves

A

Connect the periphery to the spinal cord

31 pairs formed by dorsal and ventral root

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Ventral root

A

Efferent fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Dorsal root

A

Afferent fibres

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Inner core

A

Gray matter

Neuronal cell bodies

H shaped

Ventral, lateral and dorsal horn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Outer

A

White matter

Myelinated axons

White columns/ tracts or funiculi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Gray matter organisation

A

Dorsal horn: neurones receiving sensory input

Lateral horn: preganglionic sympathetic neurones

Ventral horn: motor neurones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

White matter organisation

A

Contains tracts

Long ascending tracts carry afferent impulses within to centres within the brain

Long descending tracts carry efferent impulses from centres within the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

White matter organisation 2

A

Dorsal column: ascending reacts

Lateral column: descending and ascending tracts

Ventral column: mainly descending tracts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Ascending tracts

A

Sensory

Proprioceptive
- information originating from inside the body

Exteroceptive
- information originating from outside the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Ascending tracts- anatomy

A

Three neurones in circuit

  1. First order neurone: enters spinal cord via dorsal root
  2. Second order neurone: ascends spinal cord or brainstem
  3. Third order neurone:: projects to the cerebral cortex
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Dorsal column medial lemniscus pathway: First order neurones

A

Enter spinal cord and ascend dorsal column on same side within the:

  • fasciculus gracilis
  • fasciculus cuneatus

Fibres ascend dorsal column uncrossed

Longest neurones in body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Topographical organisation of axons

A

Fasciculus gracilis terminates in nucleus gracilis
- information from lower limb

Fasciculus cuneates terminates in nucleus cuneatus
- information from upper limb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Cauda equina

A

From dorsal ventral root of lower spinal nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Cervical enlargement

A

Innervation to upper limb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Lumbosacral enlargement

A

Innervation to lower limbs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Dorsal column medial lemniscus pathway: Second order neurones

A

Cross in medulla and second to thalamus

- form medial lemniscus

18
Q

Dorsal column medial lemniscuis pathway: Third order neurones

A

Project from thalamus to somatosensory cortex

19
Q

Lesions on one side of spinal cord

A

Loss of tactile discrimination and proprioception on same side

Sensory ataxia

Test with Romberg’s sign

e.g. multiple sclerosis

20
Q

Sensory ataxia

A

Loss of coordination and balance without visual cues

21
Q

Romberg’s sign

A

Severe swaying on standing with eyes close/ feet together

22
Q

Spinothalamic tract

A

Pain, temperature and crude touch

23
Q

Spinothalamic: first order neurones

A

Enter dorsal horn and form tract of lissauer

Synapse in dorsal horn with second order neurones

24
Q

Spinothalamic: second order neurones

A

Cross in dorsal horn at each level

Ascend in anterolateral column to thalamus

25
Q

Spinothalamic: third order neurones

A

Project from thalmus to somatosensory cortex

26
Q

Damage to anterolateral column

A

Lesions on one side of spinal cord
- loss of pain, temperature and crude touch on opposite side

Outside compression of cord
- loss of lower limb pain first

Inside grey matter tumour
- loss of upper limb pain first

27
Q

Spinocerebellar tracts

A

Unconscious muscle proprioception
- for smooth motor coordination

Two neurones only

Four tracts

Uncrossed

28
Q

Posterior spinocerebellar: first order neurones

A

Synapse in dorsal horn

29
Q

Posterior spinocerebellar: second order neurones

A

Ascend in lateral column to cerebllum

30
Q

SPinocerebellar: Lesions on one side of spinal cord

A

Uncoordinated lower limb muscular activity on same side

31
Q

Corticospinal tract

A

Great voluntary motor pathway

2 neurones in circuit

  1. Upper motor neurone: from cerebral cortex to ventral horn
  2. Lower motor neurone: from ventral horn to skeletal muscle
32
Q

Pyramidal tract

A

Primary motor cortex ->

Posterior limb of internal capsule ->

Cerebral peduncle ->

Pons ->

Pyramids of medulla ->

Lateral/ anterior corticospinal tract

33
Q

Pyramids of decussation

A

80% cross- lateral corticospinal tract

20% on same side- anterior corticospinal tract

34
Q

topographical organisation in ventral horn of corticospinal tract

A

Medial- trunk

Anterolateral- proximal limb segments

Posterolateral- distal limb segments

35
Q

Motor neurone disease

A

Disruption of the corticospinal tract

36
Q

Upper motor neurone disease

A

Degeneration of upper motor neurones

  • spastic paralysis (increased muscle tone)
  • overactive tendon reflexes
  • no significant muscle atrophy

e.g. following a stroke

37
Q

Lower motor neurone disease

A

Degeneration of lower motor neurones in ventral horn

  • flaccid paralysis (no muscle tone)
  • no tendon reflexes
  • muscle atrophy

e.g. spinal muscular atrophy

38
Q

Amyotrophic lateral sclerosis

A

Selectively affects lower and upper motor neurones

Progressive muscle weakness and atrophy but mind intact

Symptoms initially in limbs or bulbar signs

Spasticity present when upper motor neurones affected

Short life span

39
Q

Extrapyramidal tracts

A

Do not pass through the pyramids

Descending tracts from basal ganglia, cerebellum and pons

e.g. reticulospinal tract

40
Q

Reticulospinal tract

A

From reticular formation (pons) to spinal cord

Regulates ventral horn motor activity/ reflexes

Facilitates and inhibits lower motor neurones

Important for posture and locomotion

Theme 1: Neuro Anatomy (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions