Introduction to Functional Organisation of the CNS Flashcards
1
Q
What makes up the CNS?
A
Brain
Spinal cord
Retina
2
Q
What makes up the PNS?
A
Nerves
Ganglia
3
Q
Where does the long axis of the CNS bend?
A
Cephalic flexure
4
Q
What is the basic structure of the brain?
A
Cerebrum Cerebellum Brain stem Spinal cord Thalamus Hypothalamus Basal ganglia Limbic system
5
Q
How many nuclei make up the basal ganglia?
A
5
6
Q
What do the basal ganglia do?
A
Control motion and movement
7
Q
What does the limbic system do?
A
Regulate emotion
8
Q
What is grey matter?
A
Cell bodies of CNS
9
Q
Where is grey matter in the brain?
A
Edge of cerebrum
10
Q
How thick is grey matter in the brain?
A
0.5 cm
11
Q
What is white matter?
A
Axons
12
Q
What are axons?
A
Long processes from neurons
13
Q
What is myelin?
A
Insulating sheath around axons to allow transmission of information over long distances rapidly
14
Q
What is a T1 MRI image similar to?
A
Anatomical picture - white matter is white
15
Q
What is the cerebrum divided into?
A
Two cerebral hemispheres
16
Q
What divides the two cerebral hemispheres?
A
Longitudinal fissure
17
Q
What is a ridge called?
A
Gyrus; pl: gyri
18
Q
What is a groove called?
A
Sulcus; pl: sulci
19
Q
What is the cerebrum responsible for?
A
Thing that makes us, us Language Emotions Self-awareness Behaviour
20
Q
What are the four lobes of the cerebral cortex?
A
Frontal
Parietal
Temporal
Occipital
21
Q
How are the four lobes divided?
A
Broadly separated by specific structural locations
22
Q
What is the functional significance of the cerebral lobes?
A
Limited
Have broad functional differences - not specific
23
Q
What does the frontal lobe broadly control?
A
Motor control
24
Q
What does the parietal lobe broadly control?
A
Sensory control
25
What divides the frontal and parietal lobes?
Central sulcus
26
Where is the precentral gyrus?
In frontal lobe anterior to central sulcus
27
Where is the postcentral gyrus?
In parietal lobe posterior to central sulcus
28
What are Brodmann areas based on?
Cellular differences
29
Do Brodmann areas have any significance?
Yes, they have some significance
| Most advanced method of labelling brain
30
What do PET scans identify?
Areas that are metabolically active with certain stimuli
31
Which lobe is active when hearing words?
Temporal lobe
32
Which lobe is active when seeing words?
Occipital lobe
33
Which lobes are active when speaking words?
Frontal and parietal lobes
34
What does the cerebellum do?
Compares what you want to do with what you are doing
| Refines motor program
35
How can you test cerebellar function?
Touch nose with finger
| If there's a problem, person can't touch nose because muscle movements aren't corrected
36
What proportion of the neurons of the brain does the cerebellum have?
Half
37
What are the basal ganglia involved in?
Motor control
38
What do the basal ganglia do?
Select and initiate voluntary movement
39
Which part of the brain do the basal ganglia connect to and work with?
Cortex
40
What are two diseases involving basal ganglia?
Parkinson's disease
| Huntington's disease
41
What are the five nuclei of the basal ganglia?
```
Caudate
Putamen
Globus pallidus
Subthalamic nuclei
Substantia nigra
```
42
What makes up the striatum?
Caudate
| Putamen
43
Where are the basal ganglia located?
Close to midline
44
Where is the substantia nigra located?
Brain stem
45
Where is the thalamus?
In diencephalon
46
Where is the diencephalon?
A wall in the middle of the brain
47
What is the thalamus responsible for?
Sensory relay to cortex
48
What type of input is sensory input?
Afferent
49
What is the thalamus made up of?
Many nuclei
50
What is the broad role of thalamic nuclei?
Integrate info
51
What three ways do thalamic nuclei project?
```
Relay sensory information
Relay non-sensory information from cortex and basal ganglia to specific areas
Project globally to cortex
- Controls arousal and sleep
- Secondary role
```
52
Where is the hypothalamus?
Floor of diencephalon
| In middle of brain near midline
53
What does the hypothalamus do?
Regulate homeostasis
54
What does the hypothalamus control?
```
Blood pressure and electrolyte levels
Temperature
Reproduction
Energy metabolism
Stress responses
```
55
What does the brain stem control?
Unconscious survival functions
- HR
- Breathing
- Complex reflexes
- Sneezing
- Coughing
56
What are cranial nerves?
Sensory and motor control to face and deeper structures
57
What part of the brain does the spinal cord continue on from?
Medulla in brain stem
58
What encloses the spinal cord?
Vertebrae
59
Where is the grey matter in the spinal cord?
Core
60
What is the spinal cord grey matter divided into?
Dorsal horns
Ventral horns
Intermediate zone
61
What is the spinal cord white matter divided into?
Dorsal columns
Ventral columns
Lateral columns
62
What information does the dorsal part of the spinal cord carry?
Sensory
63
What information does the ventral part of the spinal cord carry?
Motor
64
Where does the spinal cord end?
Around L1/L2
65
T/F: Each vertebra has corresponding spinal segment
True
66
How many nerves does each spinal segment give rise to?
Two
67
What is the cauda equina
Continues on from spinal cord
| Individual strands of lumbar nerves
68
What forms a spinal nerve?
Dorsal root
| Ventral root
69
What information does the dorsal root carry?
Sensory
70
What information does the ventral root carry?
Motor
71
What is in a dorsal root ganglion?
Neuronal somata
72
What type of nerve is a spinal nerve, in terms of information?
Mixed
73
What type of nerve are most peripheral nerves?
Mixed
74
What is a dermatome?
Region of body innervated by bilateral pair of dorsal root ganglia
75
What is the ventricular system?
Hollow centre of brain forming ventricles
76
What does the brain sit in?
Fluid
77
Where is CSF made?
Ventricles
78
What are the names of the ventricles?
```
Lateral ventricle
- Largest
- Close to midline
Third ventricle
- Near diencephalon
Fourth ventricle
- Near cerebellum
```
79
What makes CSF?
Vascular choroid plexus
80
What is CSF?
Ultrafiltrate plasma
No cells
Little protein
81
What is the choroid plexus?
Specialised epithelial cells
82
Where is the choroid plexus?
In ventricles
83
Where does CSF flow out of the ventricles?
At fourth ventricle
84
What is the role of CSF?
Nourishes brain
| Protects brain from movement
85
What protects the brain?
Skull
| Meninges
86
What are the three layers of meninges, from out to in?
```
Dura
- Thickest
Arachnoid
- Fibrous
Pia
- Thinnest
```
87
Where is CSF absorbed into the venous system?
Arachnoid mater
88
What protects the ECF in the brain?
Blood brain barrier (BBB)
89
What is the BBB dependent on?
Tight junctions between endothelial cells in capillaries
90
What kind of transport is most common across the BBB?
Active transport
91
What happens when the BBB breaks down?
Neuron death
| Immune cells of CNS enter body > wreak havoc
