NEURO: Part 1 Flashcards
1
Q
What meninges covers the brain
A
Pia mater
2
Q
Role of the arachnoid mater
A
Nourishes surface of the brain and keeps CSF in contact with surface of the brian
3
Q
What artery divides into the meningeal vessels
A
The external carotid artery
4
Q
Where are the meningeal vessels found
A
Between bones of the skull and the dura
5
Q
What are bridging veins
A
These cross the subdural space (connect dura to arachnoid)
6
Q
In what meninges are circle of willis found
A
Subarachnoid space
7
Q
Why are there no vessels deep to th epic
A
The pia is part of the BBB
8
Q
What are oligodendrocytes
A
Myelination of axons in the CNS
9
Q
What are the counterparts to oligodendrocytes
A
Swann cells
10
Q
Main functions of the frontal brain
A
- Voluntary movement on opposite side of body
- Controls speech (contains brook’s area)
- Thought processes, reasoning and memory
11
Q
Main functions of the parietal brain
A
Receives and interprets sensations = pain, touch, pressure, shape and body-part awareness (proprioception)
12
Q
Main function of temporal brain
A
Understanding of speech (wernicke’s), memory and emotions
13
Q
Role of occipital lobe
A
Understanding visual images and meaning of written words
14
Q
Describe the passage of CSF
A
- Produced by ependymal cells in choroid plexus of lateral ventricles
- traves down third ventricle via intraventricular foramen
- Travels down to fourth ventricle via Aqueduct of Sylvius
- 4th to subarachnoid space via the one FORAMEN of magendie and two FORAMEN of Luschka
15
Q
Where is CSF re-absorbed
A
Arachnoid granulation sin saggital sinus
16
Q
What is hydrocephalus
A
Abnormal accumulation of CSF in ventricular system
17
Q
What causes hydrocephalus
A
Blocked cerebral aqueduct
18
Q
Where does the sympathetic system originate from
A
- T1-L2
19
Q
Where are sympathetic ganglia found
A
Close to spinal cord - two chains
20
Q
What hormone is used at the preganglionic synapse of sympathetic neurones
A
ACh
21
Q
What receptors does ACh bind to in the sympathetic neurone
A
Nicotinic receptors
22
Q
What do sympathetic neurones supply
A
Visceral organs and structures of superficial body regions
23
Q
Are there more ganglia in para or simp
A
Simp
24
Q
What amplifies the effect of the sympathetic nervous system
A
Adrenal glands = release adrenaline into th blood directly
25
8 outcomes of sympathetic stimulation
1. Increased HR
2. Increased force of contractions in the heart
3. Vasoconstriction
4. Bronchodilatation
5. Sphincter contraction
6. Decreased gastric secretions
7. Male ejaculation
26
What cranial nerves are parasympathetic
1973 (10,9,7,3)
27
Where do parasympathetic nerves leave the CNS
Brainstem and sacral portion
28
Where are parasympathetic cel bodies found
Brainstem
29
Where are parasympathetic ganglia found
Close to the organs the innervate
30
What does ACh bind to at post-ganglionic synapse of parasympathetic neurones
Muscarinic
31
Role of somatic nerves
Sensory and motor of bodily segments
32
Role of branchial nerves
Motor only
33
How many branchial arches are there
5
34
Two features of the autonomic nervous system
Parasympathetic and sympathetic
35
What constitutes the PNS
Nerves and ganglia outside the brain and spinal cord
36
What constitutes the CNS
1. Brain and spinal cord
37
Where do branchial nerves originate from
Brain
38
What are lower motor neurones also known as
Alpha motor neurones
39
What do alpha motor neurones innervate
Skeletal muscles that have cell bodies lying in grey matter of spinal cord and brainstem
40
Define muscle spasticity
1, When muscles do not develop increased tone UNTIL they are stretched a bit and after a brief increase in tone, contraction subsides for a short time
41
What is the CLASP-KNIFE PHENOMENON
1. When someone bends the limb of a patient, initially there is some resistance but after a certain point, resistance falls dramatically
42
In what condition is spasticity found in
Parkinson's
43
What is muscle rigidity
1. Increased muscle contraction is continuous and resistance to passive stretch is constant
44
How many vertebras are there
```
33:
7 cervical
12 thoracic
5 lumbar
4 coccyx
```
45
How many pairs of spinal nerves are found in the spinal cord
```
31:
8 - cervical
12 - thoracic
5 - lumbar
5 - sacral
coccyx - 1
```
46
At what vertebra level does the conus end at
Before L2
47
Where do all cervical segments leave th spinal cord
ONE VERTEBRA higher than corresponding vertebra (except C8 which exits below one vertebra)
48
Where do all thoracic segments leave the spinal cord
1-2 vertebra BELOW corresponding vertebra
49
Where do all lumbar segments leave the spinal cord
3-4 vertebra BELOW corresponding vertebra
50
Where do all sacral segments leave the spinal cord
5 vertebra BELOW
51
What is a dermatome
Area of skin supplied by a SINGLE SPINAL NERVE
52
Describe sensory innervation of the hand
1. Little finger - C8 (ulnar)
2. Index = C7 (median)
3. Thumb - C6
53
Sensory innervation of clavicle
C4
54
Sensory innervation of nipples
T4
55
Sensory innervation of medial arm
T1
56
Sensory innervation of umbilicus
T10
57
Sensory innervation of knee
L4
58
Sensory innervation of perianal area
S4
59
Sensory innervation of anus
S5
60
Define a myotome
Volume of muscle supplied by a single spinal nerve
61
Nerve supply of diaphragm
C3,4,5
62
Innervation of penis
S2,3,4
63
Innervation of small muscles of the hand
T1
64
What is the role of the DORSAL/Medial leminiscal column
```
Carries the following:
Touch
Vibration
Proprioception
Pressure
```
65
What four nerve endings detect touch
1. Meissner's corpuscles
2. Pancinian corpuscles
3. Ruffini Endings
4. Merkel Endings
66
What kind of neurones are upper limb and lower limb neurones
PSEUDO-UNI POLAR NEURONES
67
Where does decussation of the dorsal column leminisus column occur + what are the decussating fibres called
At the Pons
Internal arcuate fibres
68
What nucleus do the dorsal column-medial leminiscus column bind to
VENTRO POSTERO LATERAL nucleus
69
Role of lateral spintothalamic tract
Pain and temperature
70
Role of medial spinothalamic tract
Crude touch
71
Where does decussation occur in the spinothalamic tract
Spinal cord
72
At what part of the spinothalamus tract is pain consciousness processed
Thalamus
73
Role of the posterior spinocerebellar tract
Carries information on proprioception to the IPSILATERAL INFERIOR CEREBELLAR PEDUNCLE
74
Role of the anterior spinocerebellar tract
Carries information on proprioception to the CONTRALATERAL SUPERIOR CEREBELLAR PEDUNCLE
75
Where do descending tracts originate from
Cerebral cortex and brainstem (upper motor neurones)
76
What is the descending tract divided into
PYRAMIDAL
| EXTRAPYRAMIDAL
77
How many pathways in pyramidal tract
2 originating in the cerebral cortex of cranial nucleus for facial innervation
78
Where does the pyramidal tract decussate
Medulla and descends contra laterally
79
What neurones of the pyramidal tract do NOT decussate
Those innervating the axial muscles
80
Where does pyramidal tract synapse
Cell bodies of the ventral horn of the spinal grey matter
81
Name a pyramidal tract
Corticospinal tract
82
Where do extra-pyramidal tracts originate from
Brainstem
83
Role of extra-pyramidal tract
Involuntary autonomic control of all musculature
84
Name three extra-pyramidal tract
RUBROSPINAL
TECTOSPINAL
VESTIBULOSPINAL
85
Role of corticospinal tract
TRANSMIT CONTROL OF VOLUNTARY MUSCLES
86
Where does the lateral corticospinal tract decussate
MEDULLA
87
Where does the lateral corticospinal tract originate from
Contralateral motor cortex
88
Where does the medial corticospinal tract decussate
1. Leaves via anterior white commissure to axial muscles (head and trunk)
89
What does the lateral corticospinal tract innervate
Limb muscles
90
Where does the Upper motor neurone originate from
Motor cortex
91
Where can a UMN lesion occur
Cortex all the way down to the ventral horn
92
Cell bodies of lower motor neurones location
Ventral horns
93
What is the vestibulospinal tract needed for
Muscle tone
| Balance and posture by innervating antigravity muscles
94
Where are vestibulospinal tract originating from
Vestibular nucleus
95
Is Vestibulospinal tract decussating
No
96
Role of tectospinal tract
Visual stimuli causes head to turn
97
Where does the tectospinal tract originate from
Tectum: Superior colliculus
98
Does tectospinal tract decussate
At the midbrain - contralateral
99
Role of the rubrospinal tract
Facilitates flexor and inhibits extensors - fine hand movements
100
Where does the rubrospinal tract originate from
Red nucleus
101
Does the rubrospinal tract decussate
Midbrain - contralateral
102
What is Brown-Sequard Syndrome
Heme-Section of the spinal cord
103
What is brown-sequard syndrome
1. Ipsilateral weakness below lesion due to ipsilateral descending motor corticospinal tract (decussated already at medulla)
2. Ipsilateral loss of dorsal column proprioception below lesion as ascending tracts are damaged before they could desiccate
3. Contralateral loss of spinothalamic pain and temperature as spinothalamic fibres decussate just after entering the spinal cord
OVERALL:
Ipsilateral loss: proprioception, motor and fine touch
Contralateral loss: pain, temperature and crude touch
104
What is lower motor lesion
Nerve fibre can't properly innervate the muscle fibre so = flaccid paralysis
105
How is spastic paralysis caused
If nerve cuts above the alpha motor neurone which results in spastic (tense) paralysis
