Nervous System Flashcards
(83 cards)
1
Q
precentral gyrus
A
primary motor cortex - around half assigned to the face
2
Q
postcentral gyrus
A
primary somatosensory cortex - sense of what is going on around you
3
Q
reading
A
Supramarginal gyrus
4
Q
writing
A
Angular gyrus
5
Q
Fasciculi
A
bundle of fibres connecting one region of the brain to another
6
Q
the Angular gyrus has fasciculi leading to _______ ____ which is found anterior to the _________ _____. This area is responsible for planning the movement of the _____. The Supramarginal gyrus has has fasciculi leading to an area below _______ _____. This area controls the ____. Both of these areas are found in the ______ ______ gyrus.
A
the Angular gyrus has fasciculi leading to Exner’s area which is found anterior to the precentral gyrus. This area is responsible for planning the movement of the hands. The Supramarginal gyrus has has fasciculi leading to an area below Exner’s area. This area controls the eyes. Both of these areas are found in the middle frontal gyrus.
7
Q
PMC and PSSC organised
A
carefully = somatotopically (upside down stick figure)
8
Q
arcuate fasciculus
A
- white matter
- connects Wernicke’s to broca’s
9
Q
connectional/conduction aphasia
A
problem with the arcuate fasciculus.
Patient cannot copy what you say to them.
Can’t mount a logical response, but can understand and interpret speech
10
Q
formulate speech
A
Broca’s
11
Q
Frontal association cortex
A
intelligence personality behaviour mood cognitive function
12
Q
parietal association cortex
A
spatial skills 3D recognition (shapes, faces, abstract perception)
13
Q
temporal association cortex
A
memory
mood
aggression
intelligence
14
Q
______ side of the brain is responsible for language in most people
A
left (left-side dominant)
15
Q
how much of the PMC is responsible for the face
A
1/3 - 1/2
16
Q
Wernicke’s
A
- interpret speech
- receives raw information from the PAC
17
Q
aphasia =
A
inability to manage spoken word
18
Q
sensory/fluent aphasia
A
- Wernicke’s area is affected
- word salad
19
Q
motor/non-fluent aphasia
A
- problem with Broca’s area
- can’t formulate speech
20
Q
Primary auditory cortex
A
tonotopic representation
different areas receive different tones
21
Q
Primary visual cortex
A
small granule cells which allow sense of sight
22
Q
supplementary visual cortex
A
interprate sense of sight
23
Q
Non-dominant hemisphere (right - usually)
A
- non-verbal language (e.g. body language)
- emotional expression (tone of language)
- spatial skills (3D)
- conceptual understanding
- artistic/musical skills
24
Q
effects of injury on the non-dominant hemisphere
A
- loss of non-verbal language
- speech lacks emotion
- spatial disorientation
- inability to recognise familiar objects
- loss of musical appreciation
25
how many pair of spinal nerves
31 pairs = 62 total
26
```
number of pairs of each spinal cord nerve:
cervical nerves =
thoracic nerves =
lumbar nerves =
sacral nerves =
coccygeal nerves =
```
```
cervical nerves = 8
thoracic nerves = 12
lumbar nerves = 5
sacral nerves = 5
coccygeal nerves = 1
```
27
dermatome map shows...
which nerves of the spinal cord are responsible for which parts of the body
28
the Meissner corpuscle responds to _______ whereas the Pacinian corpuscle responds to _______ . The are both ________ and carry impulse at ____ m/s. They also exhibit ________ sensation - the ability to distinguish between 2 points of touch.
the Meissner corpuscle responds to _touch_ whereas the Pacinian corpuscle responds to _pressure_ . The are both _myelinated_ and carry impulse at _50_ m/s. They also exhibit _discriminative_ sensation - the ability to distinguish between 2 points of touch.
29
Pain and temperature nerve ending
- free nerve ending
- unmyelinated
- 1m/s
30
somatosensory system
touch, temprature, pain and pressure pathways
31
reflex arc
involves internal processing within the spinal cord (i.e. brain not necessarily involved)
32
dorsal columns
1. Gracile fasciculus (lower limb)
| 2. Cuneate fasciculus (upper limb)
33
which nerves travel through the gracile fasciculus?
T8 down to c1 (lower limb)
34
which nerves travel through the cuneate fasciculus
T8 upwards (upper limb)
35
Cell bodies of the nerves, travelling through the dorsal root, are found...?
in the dorsal root ganglion
36
which part of the thalamus is important for discriminative sensation?
ventral posterior nucleus
37
The pathway in the spinal cord which conveys discriminative touch and pressure sensation is know as the_______ ________- ________ _________ ___________, whereas the pathway in the spinal cord for non-discriminative pain and temperature sensation is know as the _______ ___________ _______ .
When both pathways are affected by a lesion on the right side of the spinal cord, we refer to the pattern of sensory loss as being a ______________ sensory loss, because touch and pressure are lost on the ________ side of the body, whereas pain and temperature are lost on the _________ side of the body.
The pathway in the spinal cord which conveys discriminative touch and pressure sensation is know as the _dorsal_ _column_- _medial_ _lemniscal_ _pathway_, whereas the pathway in the spinal cord for non-discriminative pain and temperature sensation is know as the _lateral_ _spinothalamic_ _tract_ .
When both pathways are affected by a lesion on the right side of the spinal cord, we refer to the pattern of sensory loss as being a _dissociative_ sensory loss, because touch and pressure are lost on the _right_ side of the body, whereas pain and temperature are lost on the _left_ side of the body.
38
A lesion involving the left side of the brainstem would result in the loss of discriminative touch and pressure sensation on the _______ side of the body, and the loss of pain and temperature on the _______ side of the body. This type of sensory loss is referred to as a ___________ sensory loss.
A lesion involving the left side of the brainstem would result in the loss of discriminative touch and pressure sensation on the _right_ side of the body, and the loss of pain and temperature on the _right_ side of the body. This type of sensory loss is referred to as a _associative_ sensory loss.
39
where do the ST and DC-ML pathways both terminate?
Ventral posterior nucleus of the thalamus
40
Myelinated fibres convey information on __________ sensations from _________ _______ _______ receptors in the skin. The unmyelinated fibres convey information on _____________ sensation from _________ ______ ________ receptors in the skin.
Myelinated fibres convey information on _discriminative_ sensations from _encapsulated_ _nerve_ ending_ receptors in the skin. The unmyelinated fibres convey information on _non-discriminative_ sensation from _free_ _nerve_ _ending_ receptors in the skin.
41
path taken in the DISCRIMINATORY system
the 1st order neuron arises in the primary root afferents and travels through the dorsal column of the spinal cord, to the gracile (lower limb) and cuneate (upper limb) nuclei.
Here, the second order neuron begins and travels up the medial lemniscus to the ventro-posterior thalamus.
From the ventro-posterior thalamus the third order neuron travels through the internal capsule to the primary somatosensory cortex.
42
path taken by the NON-DISCRIMINATORY system
the 1st order neuron arises in the primary root afferents and travels through the dorsal root ganglion of the spinal cord, to the grey dorsal horn of the spinal cord.
Here, the second order neuron begins and crosses over at the anterior white commissure to the lateral spinothalamic tract. It travels up this to the ventro-posterior thalamus.
from here, the third order neuron travels ups through the internal capsule to the primary somatosensory cortex.
43
pyramidal cells
- very triangular, the way they cross looks like pyramids
| - cell body in the upper motor neuron
44
pons contains nerves which head towards the...
face
45
to get from the upper motor neuron to the pyramidal tract, which structure does the neuron pass through?
internal capsule
46
where does the pyramidal decussation occur? what happens here?
medulla
15% of the neurons travel down the VENTRAL corticospinal tract.
85% of the neurons travel down the LATERAL corticospinal tract
47
where the ventral corticospinal tract ends...
there is an interneuron before the lower motor neuron
48
lesion on the pyramidal tract
spastic paralysis
49
lesion on the lower motor neuron
flaccid paralysis
50
spastic paralysis
- increased muscle tone (rigidity)
- decreased fine movement
- loss of control of upper motor neuron (everything before LMN)
- reflex arc do their thing unchecked
51
is there an interneuron between the lateral corticospinal tract neuron and the LMN?
no.
| there is no interneuron at the end of the lateral corticospinal tract.
52
flaccid paralysis
- decreased muscle tone
| - no muscle control
53
subcortical grey matter =
any tissue that contains cell bodies and is under the cortex
54
5 nuclei of the basal ganglia
1. caudate nucleus
2. putamen
3. globus pallidus (internal, external)
4. sub-thalamic nucleus
5. substantia nigra
55
2 parts of the substantia nigra
- pars compacta (black)
| - pars reticular (white)
56
striatum
caudate nucleus and putamen
57
Lenticular nucleus
globus pallidus and putamen
58
cerebellar cortex / cerebellum
- unconscious movement
- termination of movement
- coordination of movement
- ballistic
59
disfunction in the cerbral cortex
overshoot actions (test)
60
left cerebellum affects movement in which side of the body?
left
61
basal ganglia system function
- initiation of movement
- fine motor control
- mood through movement
62
what happens when you are learning a new golf swing?
- initially a ballistic movement by the cerebellum
| - eventually train the basal ganglia to perform a more precise movement
63
neurons from the cerebellum to the VA-VL thalamus use which neurotransmitter at their synapses? what effect does this have?
Glutamate
| +excitatory effect
64
neurons from the VA-VL thalamus to the cerebral cortex use which neurotransmitter at their synapses? what effect does this have?
Glutamate
| +excitatory effect
65
neurons from the cerebral cortex to the striatum use which neurotransmitter at their synapses? what effect does this have?
GABA
| -inhibitory effect
66
neurons from the striatum to the ext. and int. globus pallidus use which neurotransmitter? what effect does this have?
GABA
| -inhibitory effect
67
neurons from the internal globus pallidus to the VA-VL use which neurotransmitter? what effect does this have?
GABA
| -inhibitory effect
68
substantia nigra (importance, location, neurotransmitter...)
- dopamine
- critical for smooth movement and state of mind
- located in the midbrain
69
what are the upper and lower regions of the striatum responsible for?
```
Upper = motor, movement
Lower = mood, feeling
```
70
which regions of the striatum does dopamine affect? What is the significance of this?
BOTH the upper and the lower. Therefore, dopamine affects both mood and movement
71
not enough dopamine leads too...
catatonia = stiffness and rigidity
72
too much dopamine leads too...
diskinesia = wild movements
| Phsycotic
73
dopamine producing cells are very sensitive too...
reactive oxygen species and reduction of vitamins etc.
74
There are two dopamine receptors:
D1 which receives_________ and
D2 which receives __________.
There are two dopamine receptors:
D1 which receives _DOPAMINE_ and
D2 which receives _LEVO-DOPA_.
75
role of the nigrostriatal pathway
Holds the striatum nerves at a point where they are just about to fire. Await the input of glutamate.
76
which part of the substantia nigra produces dopamine
pars compacta
77
what is special about levo-dopa?
it can cross the blood-brain barrier
78
tonically active (+example)
always active e.g. the neurons of the striatum innervating the globus pallidus
79
Parkinson's Disease
Loss of dopamine cells in the substantia nigra pars compacta (SNc) and a depletion of dopamine in striatum as a result.
80
consequence of Parkinson's
1. striatum gets no input of dopamine (from nigrostriatal pathway)
2. GABAergic cells, from the basal ganglia to the VA-VL can fire as much as they want
3. results in hypokinesia, due to the strong inhibitory effect reducing the effect of glutmate
81
ih a healthy human brain, striatum cells fire when...
a drop of glutamate arrives
82
4 symptoms of parkinsons
1. mood - emotionally flat
2. bradykinesia (HYPOKINESIA)
3. tremor at rest ('pill-rolling')
4. rigidity
83
The most recently developed surgical treatment of Parkinson's disease is _________ of the region in the basal ganglia known as the ________ ________.
The other surgical treatment is a __________ of the region of the thalamus known as the _______.
Other, non-surgical, treatment involves dopamine replacement using ________.
Deep Brain stimulation involves placing an electrode in the _____ and ________.
The most recently developed surgical treatment of Parkinson's disease is _pallidotomy_ of the region in the basal ganglia known as the _globus_ _pallidus_int_.
The other surgical treatment is a _thalamotomy_ of the region of the thalamus known as the _VA-VL_.
Other, non-surgical, treatment involves dopamine replacement using _leva-dopa_.
Deep Brain stimulation involves placing an electrode in the _GPi_ and _subthalamic_nucleus_.
