L9 - localisation Flashcards
1
Q
how thick is the cerebral cortex
A
2-4mm
2
Q
role of gyri and sulci
A
increase surface area
3
Q
lamina
A
layers of cortex
4
Q
central sulcus
A
divides frontal and parietal lobes
5
Q
lateral sulcus
A
divides the frontal and temporal lobes
6
Q
parieto-occipital sulcus
A
separates parietal and occipital lobes
7
Q
cingulate sulcus
A
runs parallel with corpus callocum
8
Q
shape of cingulate sulcus
A
C shaped
9
Q
where can the cingulate sulcus be seen
A
medial view
10
Q
collateral sulcus
A
indicates position of parahippocampal gyrus
11
Q
location of collateral sulcus
A
hooks backwards on itself to form a medially projected bump - uncus
12
Q
which lobe is the collateral sulcus part of
A
temporal
13
Q
role of limbic lobe
A
emotion and memory
14
Q
uncas
A
bottom part of limbic lobe
15
Q
uncal herniation
A
if the uncus herniates below the cerebella, resulting in the uncus pressing on the midbrain
16
Q
potential sites of uncal herniation
A
beneath the free edges of the meninges
17
Q
consequence of uncal herniation
A
compression on the brainstem
18
Q
tonsils herniation
A
when tonsils in the cerebellum herniate and compress on the medulla oblongata
19
Q
brodmann’s area
A
cortical map divided into 46 areas based on cellular organisation of the cerebral cortex
20
Q
primary projection areas
A
perceive sensory or motor information
21
Q
primary sensory areas
A
where specific sensory pathways terminate / how we perceive sensation
22
Q
primary motor areas
A
specific motor pathways originate here
23
Q
a lesion in Broca’s area can affect which artery?
A
middle cerebral artery
24
Q
what do cerebral hemispheres include?
A
Include a dense core of white matter with an overlying thin layer of grey matter (cortex)
25
how many layers are there in the laminar arrangement of the cerebral cortex?
6
26
herniation of the brain below the tentorium cerebelli
uncal herniation
27
The parahippocampal gyrus hooks back on itself to form which structure?
the uncus
28
Which two gyri together form the limbic lobe?
Cingulate gyrus and parahippocampus gyrus
29
secondary projection sensory areas
- Receive input from primary sensory area
| - Involved in interpretation / understanding
30
secondary motor areas
- Sends output to primary motor area
| - Organises patterns of movement
31
location of primary motor cortex
pre-central gyrus
32
what does the primary motor cortex control?
voluntary contraction of specific muscles
| it is somatotopically organised
33
what type of fibres are located in the PMC
descending motor fibres
34
location of association motor areas
anterior to PMC
35
BA 6 supplementary motor (sm) and pre-motor (pm) performs what movements?
- learned complex motor activities
- storage of those activities
e. g., tying shoe laces
36
BA 8 - frontal eye field location
frontal lobe
37
BA 8 - frontal eye field performs what movements?
controls voluntary movements of the eyes
38
BA 44, 45 (Broca's area) controls what movements?
Regulates pattern of breathing and vocalization needed for normal speech
- How you articulate your language
39
location of Broca's area
inferior frontal gyrus (typically localised to dominant hemisphere - usually left)
40
what would happen in an injury to the precentral gyrus
impaired movement or paralysis
41
what would happen in an injury to the motor associated areas
we would still be able move yet we would lose the ability to perform highly skilled movements
42
primary somatosensory cortex
post-central gyrus
43
The primary sensory cortex receives sensory pathways for which 5 senses?
- touch
- temperature
- vibration
- pain
- proprioception
44
Which 2 parts of the thalamus process sensory information, before relaying to the primary somatosensory cortex?
VPL (ventral posterior lateral) & VPM (ventral posterior medial) nuclei
45
route of information to PSC
- ascending sensory fibres towards post-central gyrus
| - information is stopped in specific areas of the thalamus before relayed to the PSC
46
thalamus nuclei
used to discriminate where the information is coming from
47
Where does the lateral VPL receive input from?
From the leg and projects to the midline
48
Where does the medial VPL receive input from?
From arm and projects to lateral region
49
In somatotropin organisation, from lateral to medial, what is the order of the arms, legs, trunk and face?
Face
Arms
Trunk
Legs
FATL
50
Where does the VPM receive input from?
From the face and projects to the lateral region
51
location of association somatosensory areas - BA5,7
superior parietal lobe
52
What is the role of BA5, 7 - association somatosensory areas?
- interpretation, understanding and recognition
- spatial analysis
- identifies type of touch
53
injury to association association somatosensory areas (BA5, 7)
tactile agnosia
- cannot recognise the object they are touching
- however can still feel it
54
Where is the primary auditory cortex located (BA41, 41)?
Superior temporal gyrus (Heschl's gyrus)
55
What is the role of the primary auditory cortex (BA41, 42)?
- conscious perception of sound
(however does not know the meaning of the sound as it is a primary not secondary cortex)
- it is tonotopically organised
56
where does the primary auditory cortex receive signals from
- vestibulocochlear nerve and the nerve sends projections to the thalamus
- which knows where the information is coming from and where it needs to go
- sends to superior temporal gyrus
57
tonotopically organised
- Specrum of auditble frequencies is mapped onto the primary auditory cortex
- Lower frequencies are projected more medially
- Higher frequencies are projected more posteriorly
58
where are higher frequency sounds organised
more posteriorly
59
Which part of the thalamus relays sound information to the primary auditory cortex?
Medial geniculate nucleus
60
role of association auditory cortex BA22
gives meaning / significance to sound
61
location of BA22 association auditory cortex
surrounds primary auditory area
62
wernicke's area
Interpretation of written or spoken word
63
primary visual cortex BA17 location
Located in the area around calcarine sulcus and occipital lobe
64
The primary visual cortex receives information from where?
The retina
65
role of association visual area BA18,19
- involved in interpretation of visual info
| - recognises faces, objects
66
What is the consequence of a lesion to the association visual areas?
Prosopagnosia
| - the inability to recognise faces
67
location / distribution the taste cortex?
Taste cortex extends from the inferior margin of the post central gyrus into the insula
68
what is the general association cortex involved in?
- involved in more complex aspects of behavioural and intellectual functioning
69
What are the roles of the prefrontal cortex?
- regulates moods and feelings
- involved in higher order cognitive functions
- involved in conceptualisation, planning and judgement
70
What are the roles of the parieto-temporal cortex?
- integrates information from different modalities
- involved in memory
- vision, hearing,touch and gives it all morning
71
aphasia
loss of ability to use language for speech
72
'dys'
difficulty
73
language centres within the dominant hemispheres
broca's and wernicke's
74
location of broca's area
inferior margin of the frontal lobe
75
What is the difference between dysphasia and aphasia?
```
dysphasia = difficulty with speech
aphasia = loss of ability to speak properly
```
76
damage to broca's area
- motor/non-fluent aphasia
| - inability to correctly articulate speech despite understanding it perfectrly
77
damage to wernicke's area
- sensory / fluent aphasia
- inability to understand language
- when speaking, words come out fluently yet do not make sense
78
arcuate fasciculus
association fibres which connect areas within hemispheres
| - important in connecting broca's and wernicke's area
79
conduction aphasia
- impaired repetition
| - can understand information however pathway is damaged so cannot repeat as cannot articulate speech
80
function of dominant hemisphere
- Linguistic function
| - Numerical skills
81
non-dominant hemisphere
- Spatial awareness
82
apraxia
Damage to secondary motor areas leads to inability to carry out purposive movements, although there is no paralysis
