week 6 Flashcards
1
Q
what is another name for a stroke
A
- cerebral vascular accident
- or shock
2
Q
what would happen if a stroke involves the right internal capsule
A
- paralysis would be on upper and lower left limbs
- because motor pathways are crossed
3
Q
what is the thalamus
A
- grey matter deep in the brain
- last of the neuron fo sensory cortex passes through here
- 3rd order sensory neurons
4
Q
what is the lentiform nucleus
A
- part of basal ganglia
5
Q
what does the basal ganglia do
A
- co-ordinates smooth muscle contractions
6
Q
what happens if there is problems with basal ganglia
A
- get irregular movements
7
Q
what is the corticospinal tact
A
- motor pathways that run through the internal capsule
8
Q
what is the internal capsule
A
- white matter between the lentiform nucleus and the thalamus
9
Q
what is the motor decussation
A
- where nerves cross over to other side to innervate
10
Q
what are the cranial nerves that supply muscles
A
- oculomotor supplies extraocular
- trochlear supplies superior oblique
- trigeminal supplies muscles of mastication
- abducens supplies lateral rectus
- facial nerve supplies muscles of facial expression
- glossopharyngeal supplies stylopharyngeus
- vagus supplies muscles of pharynx and larynx
- accessory supplies pharynx and larynx and SCM and trapezius
- hypoglossal supplies muscles of the tongue
11
Q
what is a nucleus
A
- place where cell bodies are clustered together
12
Q
what are pharyngeal arches
A
- give rise to certain muscle
13
Q
what nerve does the first arch arise from
A
- trigeminal
14
Q
what nerve does the 2nd arch arise from
A
- facial
15
Q
what muscle does the 3rd pharyngeal muscle give rise to
A
- stylopharyngeus
16
Q
what are the 4th and 6th arches from
A
- vagus nerve
17
Q
what are somites
A
- neurons that form near the midline
18
Q
where are neurons from pharyngeal arches situated
A
- more out to the side than somites
19
Q
what is the nucleus ambiguous
A
- a shared nucleus in the medulla for 9th, 10th and 11th nerves
20
Q
why do cranial nerves give innervation to both sides of the body
A
- so that when one side is damaged, the other motor cortex will still be able to innervate fibres
- apart from lower motor neurons of facial nerve which is only supplied by the opposite side
21
Q
what is the central sulcus of the brain
A
- little groove running all the way
22
Q
what does the central sulcus do
A
- separates the frontal lobe from parietal
23
Q
where is the pre-central gyrus
A
- in front of central sulcus
- where the primary motor cortex is
24
Q
where is the post-central gyrus
A
- behind the central sulcus
- primary somatic sensory cortex is here
25
what does the parieto-occipital sulcus do
- separates parietal lobe from occipital lobe
26
what is in the occipital lobe
- specific cortex which is called the primary visual cortex
27
what does the lateral sulcus do
- separates temporal lobe from parietal
28
what does the temporal lobe do
- has specific cortex in it called primary auditory cortec
| - take sound and hearing from inner ear to this area so we can perceive different things
29
what does Broca's area do
- controls muscles of speech
30
where does the occipital lobe end
- transverse fissure
31
what is white matter
- myelinated axons
| - transmission tissue
32
what is the cerebral cortex made up of
- grey matter
| - unmyelinated cell bodies
33
what are ventricles
- cavities in the brain and brainstem
| - contain CSF
34
what is the hippocampus
- bottom of lateral ventricle
| - role in memory and emotions
35
what is corpus collosum
- made up of commissionable fibres that allow for transmission of impulses from lateral hemispheres to each other
- damaged during concussions
- women have more
36
why are women better at multitasking
- have more fibres of corpus collosum
37
what does the thalamus do
- relay station for a lot of sensory information
| - has a stalk that connects to pituitary gland
38
what is the pineal gland part of
- thalamus
39
what is the diencephalon made up on
- 3 things
- thalamus
- hypothalamus
- epithalamus
40
what drains the 3rd ventricle
- cerebral aqueduct
41
what drains the lateral ventricle
- 3rd ventricle through intra-ventricular foramen
42
what does the superior colliculi do
- be able to move
| - reflective movement of your head in response to some visual stimulus
43
what does the inferior colliculi do
- reflective head movements to auditory stimulus
44
what are cerebral peduncles
- like a stalk
- projective fibres that carry sensory information up to the cerebrum
- around the midbrain
45
where do descending motor fibres cross
- pyramid of medulla oblongata
46
what are olives
- broken into superior and inferior
- superior play a role in auditory pathways
- inferior play role in proprioception and hearing
47
what is the cerebellum made up of
- grey and white matter
- grey matter on edges
- grooves on back called folia which are folds
48
what is the vermis
- worm-like structure between 2 sides
49
where is the fall cerebri
- between the vermis
| - is a dural septa
50
where does the olfactory nerve go
- olfactory epithelium pick up different things and carry it up through cribriform plate to olfactory bulb
- sensory nerve
51
what does the optic nerve do
- cross at optic chiasma
- pick up sensation on vision and take it to primary vision cortex in the cerebrum
- runs though optic canal
52
what does oculomotor nerve do
- comes out between peduncle fossa at the midbrain
| - runs through superior orbital fissure and supplies a lot of extra-ocular muscles
53
what does trochlear nerve do
- runs through superior orbital fissure and supplies superior oblique muscle
54
what does trigeminal nerve do
- spits into 3 branches
- opthalmic
- maxillary
- mandibular
- supplies muscles of mastication and certain areas of skin on face
- motor and sensory nerve
55
what holes do trigmeinal branches run through
- ophthalmic = superior orbital fissure
- maxillary = foramen rotundum
- mandibular = foramen ovale
56
what does the abducens nerve do
- runs through superior orbital fissure
| - supplies lateral rectus
57
what nerves go through superior orbital fissure
- oculomotor
- trochlear
- abducens
- ophthalmic division of trigeminal w
58
what holes does facial nerve fo through
- stylomastoid foramen and internal acoustic meatus
59
what does facial nerve do
- supplies muscle of facial expression, a lot of glands and also picks up sensation
- motor and sensory nerve
60
what does vestibulocochlear nerve do
- runs through internal acoustic meatus
| - carries dynamic and static equilibrium and just hearing
61
what does glossopharyngeal nerve do
- runs through jugular foramen
| - supplies tongue, muscles of pharynx, sensations from baroreceptors
62
what does vagus nerve do
- main parasympathetic nerve
- carries 90% flow
- runs through jugular foramen
- supplies many organs such as heart and lungs
63
what are the 2 parts of the accessory nerve
- one on cervicla part of spinal cord and on on medulla
| - cervical branch comes off foramen magnum and merges with the brand off the medulla then runs through jugular foramen
64
what does the accessory nerve do
- supply trapezius muscle and SCM
| - mainly a motor nerve
65
what does the hypoglossal nerve do
- runs through hypoglossal canal and supplies extrinsic muscles of the tongue
- mainly motor nerves
66
what does lateral fissure do
- separates frontal and temporal lobes
67
where is the visual cortex
- at the back of the brain on medial side of occipital lobe
68
where is the motor speech area-
on left side
- area used when starting to put words together
- left hemisphere of frontal lobe
69
what is the transverse temporal gyri
- auditory cortex
- sound received in these and the surrounding cortex is called the auditory association cortex or the receptive language area
- interprets sound so we can understand them
70
where is the central sulcu
- halfway between anterior and posterior poles
| - comes almost to lateral fissure but not quite
71
what makes the central sulcus different from the other grooves on the brain
- relatively straight and the same in most people
72
where is the primary sensory/somaesthetic cortex
- post central gyrus
| - behind the central sulcus
73
where is the primary motor cortex
- pre-central gyrus
| - area in fron of the central sulcus
74
what area of the sensory and motor cortex is associated with head and neck
- lower third
75
what area of the sensory and motor cortex is associated with upper limb
- above the area for head and neck
76
what area of the sensory and motor cortex is associated with trunk
- above area for upper limb
77
what area of the sensory and motor cortex is associated with lower limb
- above area for trunk
78
what is somatotopic localisation
- the phenomenon of how different parts are devoted to different areas of the body
- concept that certain parts of the body are represented in different parts of the brain
79
what does the amount of cortex reflect upon
- the activity in each part of the body
80
what size fo sensory cortex is for head and neck
- quite large as it is a very sensitive region
81
what size of sensory cortex is for upper limb
- quite large as fingertips are quite sensitive
82
what size of sensory cortex is for trunk and lower limb
- quite small area
83
what size of motor cortex is for head and neck
- a lot as need movement to speak
84
what size of motor cortex is for upper limb
- large area as need fine movements for fingers
85
what size of motor cortex is for lower limb and trunk
- quite small
86
where is the midbrina
- immediately below the cerebral hemisphere
87
where does the medulla meet the spinal cord
- around the level of the foramen magnum
88
what is the corona radiata
- where the fibres come together
| - white matter
89
where are the internal and external capsules
- internal capsule is between the lentiform nucleus and the thalamus
- external capsule is on the other side of the lentiform nucleus
90
where do neurons cross
- lower medulla area
| - decussation
91
why is the internal capsule a weak area
- a blockage in one artery can cause the whole capsule to be blocked which can lead to paralysis of upper and lower limb on opposite side of the body
92
where does the corticospinal tract run
- through the posterior limb of internal capsule
- quite narrow space
- runs from upper limb to lower limb fibres down through the corona radiata through the internal capsule and down the midbrain and pons and medulla till it crosses over
93
what is the olive
- bulge on side of medulla
94
where is the nuclei for oculomotor and trochlear nerve
- in the midbrain
95
which nuclei are in the pons
- trigeminal
- abducens
- facial nerve
96
which nuclei are in the medulla
- nucleus ambiguous for 9, 10 and 11
| - hypoglossal nucleus
97
what are nuclei that are formed near midline of the brainstem
- somites
98
what are nuclei that are on the outside of the brainstem
- formed from pharyngeal arches
99
which cranial nerve are purely sensory
- 1, 2 and 8
100
where does input for cranial nerves come from
- head and neck area of motor cortex
| - start of corticonuclear pathway
101
where does the corticonuclear pathway go
- runs alongside the corticospinal pathway
- from head and neck area of motor cortex
- lower third of motor cortex devoted to head and neck
- pass through corona radiata to join the corticospinal fibres at the internal capsule
- then, they all run through internal capsule
- corticonuclear fibres cross as they approach the level of nucleus but some also stay on same side
- corticospinal fibres all go to opposite side
102
what is the difference between corticonucleur tract and corticospinal
- corticonuclear fibres crossover to other side but also keep some fibres on the same side
- all corticospinal fibres cross over to the other side
103
where do vertebral arteries come from
- subclavian artery and through transverse process
104
what do th right and left vertebral arteries come together to form
- the basilar artery
105
what does the basilar artery go
- gives off branches as it runs along to go to cerebellum
- once reach the upper pons and about to go into midbrain it splits into 2 = right and left cerebral arteries which supply more posterior parts and under parts of cerebral hemisphere
106
where is the right internal carotid artery
- very close to pituitary stalk and optic chiasm
107
what does the internal carotid artery split into
- middle and anterior cerebral arteries
| and posterior communicating artery
108
what is the circle of arteries in the brain called
- circle of Willis
109
what do the lenticulostriate arteries do
- give supply to internal capsule
| - easy for these to block and cut off blood supply to internal capsule which leads to stroke and paralysis
110
what can happen to patients in middle life at the circle of Willis
- get little aneurysms which can burst and give a subarachnoid haemorrhage
- severe headache and rapid loss of consciousness
- common cause of sudden death
- patient would have blood stained CSF
111
what does damage to the internal capsule cause
- paralysis to the upper and lower limb on the opposite side as well as paralysis of lower face and tongue
112
what happens if middle cerebral artery is blocked
- upper limb and head and neck regions of motor and sensory cortex are in that area so become paralysed
- lower limb is not in this section so would be fine
113
what happens if the left motor cortex is affected that doesn't matter on the right
- motor speech area affected
| - if speech is unintelligible then that is a sign that the left side is affected
114
how does someone with a cortex lesion differ from someone with a internal capsule lesion
- more confused
115
what is the cerebellum supplied by
- superior, anterior interior, and posterior inferior cerebellar arteries
116
where does the internal carotid artery enter
- through the carotid canal in the temporal bone
117
what does corpus callosum do
- connecting right hemisphere to left
| - communicate through this
118
where is CSF made
- lateral ventricle
