Topography of the Brain Flashcards
(75 cards)
1
Q
Where is the seat of consciousness located?
A
Cerebrum
2
Q
What part of the brain is responsible for balance and coordination?
A
Cerebelum
3
Q
What does the brainstem contain?
A
- Vital centres
- Pathway for fibre tracts
- Location of cranial nerve nuclei
4
Q
What are the 3 components of the brainstem?
A
- Midbrain
- Pons
- medulla
5
Q
What ventricles are found in the brain?
A
- Lateral ventricles
- III ventricle
- Cerebral aqueduct
- IV ventricle
6
Q
Where are the lateral ventricles found?
A
Within the cerebral hemispheres
7
Q
Where is the III ventricle found?
A
Within the diencephalon
8
Q
Where is the cerebral aqueduct found?
A
Within the midbrain
9
Q
Where is the IV ventricle found?
A
Between pons and medulla (in front) ad cerebellum (at the back)
10
Q
Where is the CSF found?
A
- Inside the ventricles
- Between pia and arachnoid mater
11
Q
What forms the CSF?
A
Choroid plexus in each lateral ventricle
12
Q
Where is the CSF absorbed?
A
Absorbed into the superior sagittal sinus (venous channel in the brain) by the arachnoid villi
13
Q
What are the functions of the brainstem?
A
- Pathway for fibre tracts running between higher and lower centres
- Brainstem nuclei are involved with 10 of the 12 cranial nerves, so innervation of head and neck
- Brainstem centres produce the rigidly programmed automatic behaviours essential for survival
14
Q
What cavity is located in the medulla (oblongata)?
A
IV ventricle
15
Q
What does the medulla continue as inferiorly?
A
Spinal cord at foramen magnum of cranium
16
Q
What does the lower part of the medulla resemble in structure?
A
Spinal cord
17
Q
What are the surface features of the medulla?
A
- Pyramids and their decussation (crossing over)
- Olives laterally
- Connected to cerebellum by inferior cerebellar peduncle
- Cranial nerves IX, X, XI and XII from its surface
18
Q
What is the caudal part of the medulla closed around?
A
IV ventricle
19
Q
What is the cranial part of the medulla open with?
A
IV ventricle posteriorly
20
Q
What does the white matter of the medulla contain?
A
- Pyramidal tract
- Medial lemniscus
- Inferior cerebellar peduncle
- Other tracts
21
Q
What does the grey matter of the medulla contain?
A
- Cranial nerve nuclei and inferior olivary nucleus
- Nucleii of the reticular formation (vital centres)
- Sensory nuclei (gracile and cuneate)
22
Q
What is posterior to the pons?
A
IV ventricle
23
Q
What are the surface features of the pons?
A
- Middle cerebellar peduncle
- Cranial nerves V, VI, VII and VIII originate from its surface
24
Q
What does the white matter of the pons contain?
A
- Middle cerebellar peduncle
- Medial lemniscus (sensory)
- Pyramidal tract (motor)
25
What does the grey matter of the pons contain?
- Cranial nerve nuclei
- Pontine nuclei
- Nucleii of reticular formation
26
What does the midbrain develop from?
Mesencephalon
27
What is the central cavity of the midbrain?
Cerebral aqueduct
28
What are the surface features of the midbrain?
- Cerebral peduncle
- Superior cerebellar peduncle
- Corpora quadrigemina (superior and inferior colliculus)
- Origin of the oculomotor and trochlear nerves
29
What is the only nerve to originate posteriorly?
Trochlear
30
What will you always see in section of the midbrain?
Substantia nigra
31
What components will be seen on horizontal section of the midbrain?
- Central cavity (cerebral aqueduct)
- Periaqueductal grey matter with nucleus for III and IV cranial nerves
- White matter with embedded nuclei surrounds the periaqueductal grey mater
32
What does the cerebral aqueduct connect?
Connect III and IV ventricles
33
What separates the right and left hemispheres of the cerebellum?
Vermis
34
What lobes are present on each hemisphere of the cerebellum?
- Anterior
- Posterior
- Fluccoluonodular
35
What does the surface of the cerebellum have?
Sulci and folia
36
How is the cerebellum connected to the brainstem?
Via three cerebellar peduncles
37
What is found in the grey matter of the cerebellum?
- Cortex on surface
| - Deep nuclei
38
What is found in the white matter of the cerebellum?
- Arbor vitae
| - Cerebellar peduncles
39
What is the function of the cerebellum?
- Posture maintenance
| - Fine tuning motor activity
40
What is abnormality of the cerebellum known as?
Ataxia
41
What tests are there for ataxia?
- Finger-nose test
- Knee heel test
- Walking in a straight line
42
Where does the cerebellum receive information from?
- Pyramidal tracts (motor intention of brain)
- Ipsilateral proprioceptors from periphery
- Vestibular nuclei re. balance and posture
43
What does the cerebellum calculate upon receiving information?
Calculates best way to coordinate force, direction, extent of muscle contraction to maintain posture prevent overshoot and ensure smooth coordinated muscle contraction
44
What does the cerebellum 'send' once it has received information?
Sends 'blueprint# back to cerebral cortex via superior cerebellar peduncle
45
Where is the diencephalon found?
Deep within cerebral hemispheres around III ventricle
46
What does the diencephalon develop from?
Diencephalic vesicle (part of forebrain vesicle)
47
What are the paired structures of the diencephalon?
All are mainly grey matter
- Thalamus
- Hypothalamus (and pituitary)
- Epithalamus (pineal gland)
48
What does the thalamus mainly contain?
Groups of nuclei
49
What groups of nuclei does the thalamus contain?
- Anterior
- Medial
- Lateral
50
What is the lateral group of nuclei of the thalamus involved in?
Processing sensory information
51
What is the thalamus?
A sensory relay station
52
Where is the hypothalamus?
Lies below the thalamus separate from it by the hypothalamic sulcus
53
What is the hypothalamus?
The main visceral control centre
54
What is the hypothalamus essential for?
Overall homeostasis
55
What is the homeostatic role of the hypothalamus?
- Autonomic control centre
- Body temperature regulation
- Regulation of food intake
- Regulation of water balance an thirst
- Regulation of sleep-wake cycle
- Control of endocrine system functioning
56
What is the blood supply to the brain?
- Internal carotid arteries
| - Vertebral arteries
57
How do the internal carotid arteries enter the brain?
Through the carotid canal of the skull (Foramen lacerum) t
58
How do the vertebral arteries enter the brain?
Through the foramen magnum
59
What branches of the ICA supply the brain?
- Anterior cerebral artery
- Middle cerebral artery
- Posterior communicating arteries
60
What do the ACA and MCA supply?
A large part of the cerebral hemispheres
61
What do the 2 vertebral arteries join together to form?
Basilar artery
62
Where is the basilar artery?
Ventral surface of the brainstem
63
What do the branches of the vertebra-basilar system supply?
Brainstem and cerebellum
64
Where does the basilar artery end?
Level of the midbrain
65
How does the basilar artery end?
Divides into the posterior cerebral arteries
66
What do the posterior cerebral arteries supply?
The posterior part of the cerebral hemispheres
67
How is the Circle of Willis formed?
Branches of the ICA join with those of the opposite side and with the PCA
68
What is the protective feature of the Circle of Willis?
Protective against vaso-occlusion of large arteries
69
What are effectively end arteries?
The branches of the ICA supplying the cerebral hemispheres distal to the circle of willis
70
What does the anterior cerebral artery supply?
Medial aspect of cerebral hemispheres excluding occipital lobe
71
What does the middle cerebral artery supply?
Lateral aspect of cerebral hemispheres
72
What does the posterior cerebral artery supply?
Inferior aspect of cerebral hemispheres and occipital lobe
73
Where doe the veins of the brain drain into?
Superficial and deep veins of the brain drain into venous sinuses
74
Where are the venous sinuses found?
Between the 2 layers of dura mater
75
What do the dural venous sinuse drain into?
The dural venous sinuses join together to ultimately drain into the internal jugular veins
