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Flashcards in Nervous System Deck (83)
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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
Q

how many pair of spinal nerves

A

31 pairs = 62 total

26
Q
number of pairs of each spinal cord nerve:
cervical nerves = 
thoracic nerves = 
lumbar nerves = 
sacral nerves = 
coccygeal nerves =
A
cervical nerves = 8
thoracic nerves = 12
lumbar nerves = 5
sacral nerves = 5
coccygeal nerves = 1
27
Q

dermatome map shows…

A

which nerves of the spinal cord are responsible for which parts of the body

28
Q

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.

A

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
Q

Pain and temperature nerve ending

A
  • free nerve ending
  • unmyelinated
  • 1m/s
30
Q

somatosensory system

A

touch, temprature, pain and pressure pathways

31
Q

reflex arc

A

involves internal processing within the spinal cord (i.e. brain not necessarily involved)

32
Q

dorsal columns

A
  1. Gracile fasciculus (lower limb)

2. Cuneate fasciculus (upper limb)

33
Q

which nerves travel through the gracile fasciculus?

A

T8 down to c1 (lower limb)

34
Q

which nerves travel through the cuneate fasciculus

A

T8 upwards (upper limb)

35
Q

Cell bodies of the nerves, travelling through the dorsal root, are found…?

A

in the dorsal root ganglion

36
Q

which part of the thalamus is important for discriminative sensation?

A

ventral posterior nucleus

37
Q

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.

A

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
Q

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

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
Q

where do the ST and DC-ML pathways both terminate?

A

Ventral posterior nucleus of the thalamus

40
Q

Myelinated fibres convey information on __________ sensations from _________ _______ _______ receptors in the skin. The unmyelinated fibres convey information on _____________ sensation from _________ ______ ________ receptors in the skin.

A

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
Q

path taken in the DISCRIMINATORY system

A

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
Q

path taken by the NON-DISCRIMINATORY system

A

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
Q

pyramidal cells

A
  • very triangular, the way they cross looks like pyramids

- cell body in the upper motor neuron

44
Q

pons contains nerves which head towards the…

A

face

45
Q

to get from the upper motor neuron to the pyramidal tract, which structure does the neuron pass through?

A

internal capsule

46
Q

where does the pyramidal decussation occur? what happens here?

A

medulla
15% of the neurons travel down the VENTRAL corticospinal tract.
85% of the neurons travel down the LATERAL corticospinal tract

47
Q

where the ventral corticospinal tract ends…

A

there is an interneuron before the lower motor neuron

48
Q

lesion on the pyramidal tract

A

spastic paralysis

49
Q

lesion on the lower motor neuron

A

flaccid paralysis

50
Q

spastic paralysis

A
  • increased muscle tone (rigidity)
  • decreased fine movement
  • loss of control of upper motor neuron (everything before LMN)
  • reflex arc do their thing unchecked
51
Q

is there an interneuron between the lateral corticospinal tract neuron and the LMN?

A

no.

there is no interneuron at the end of the lateral corticospinal tract.

52
Q

flaccid paralysis

A
  • decreased muscle tone

- no muscle control

53
Q

subcortical grey matter =

A

any tissue that contains cell bodies and is under the cortex

54
Q

5 nuclei of the basal ganglia

A
  1. caudate nucleus
  2. putamen
  3. globus pallidus (internal, external)
  4. sub-thalamic nucleus
  5. substantia nigra
55
Q

2 parts of the substantia nigra

A
  • pars compacta (black)

- pars reticular (white)

56
Q

striatum

A

caudate nucleus and putamen

57
Q

Lenticular nucleus

A

globus pallidus and putamen

58
Q

cerebellar cortex / cerebellum

A
  • unconscious movement
  • termination of movement
  • coordination of movement
  • ballistic
59
Q

disfunction in the cerbral cortex

A

overshoot actions (test)

60
Q

left cerebellum affects movement in which side of the body?

A

left

61
Q

basal ganglia system function

A
  • initiation of movement
  • fine motor control
  • mood through movement
62
Q

what happens when you are learning a new golf swing?

A
  • initially a ballistic movement by the cerebellum

- eventually train the basal ganglia to perform a more precise movement

63
Q

neurons from the cerebellum to the VA-VL thalamus use which neurotransmitter at their synapses? what effect does this have?

A

Glutamate

+excitatory effect

64
Q

neurons from the VA-VL thalamus to the cerebral cortex use which neurotransmitter at their synapses? what effect does this have?

A

Glutamate

+excitatory effect

65
Q

neurons from the cerebral cortex to the striatum use which neurotransmitter at their synapses? what effect does this have?

A

GABA

-inhibitory effect

66
Q

neurons from the striatum to the ext. and int. globus pallidus use which neurotransmitter? what effect does this have?

A

GABA

-inhibitory effect

67
Q

neurons from the internal globus pallidus to the VA-VL use which neurotransmitter? what effect does this have?

A

GABA

-inhibitory effect

68
Q

substantia nigra (importance, location, neurotransmitter…)

A
  • dopamine
  • critical for smooth movement and state of mind
  • located in the midbrain
69
Q

what are the upper and lower regions of the striatum responsible for?

A
Upper = motor, movement
Lower = mood, feeling
70
Q

which regions of the striatum does dopamine affect? What is the significance of this?

A

BOTH the upper and the lower. Therefore, dopamine affects both mood and movement

71
Q

not enough dopamine leads too…

A

catatonia = stiffness and rigidity

72
Q

too much dopamine leads too…

A

diskinesia = wild movements

Phsycotic

73
Q

dopamine producing cells are very sensitive too…

A

reactive oxygen species and reduction of vitamins etc.

74
Q

There are two dopamine receptors:
D1 which receives_________ and
D2 which receives __________.

A

There are two dopamine receptors:
D1 which receives DOPAMINE and
D2 which receives LEVO-DOPA.

75
Q

role of the nigrostriatal pathway

A

Holds the striatum nerves at a point where they are just about to fire. Await the input of glutamate.

76
Q

which part of the substantia nigra produces dopamine

A

pars compacta

77
Q

what is special about levo-dopa?

A

it can cross the blood-brain barrier

78
Q

tonically active (+example)

A

always active e.g. the neurons of the striatum innervating the globus pallidus

79
Q

Parkinson’s Disease

A

Loss of dopamine cells in the substantia nigra pars compacta (SNc) and a depletion of dopamine in striatum as a result.

80
Q

consequence of Parkinson’s

A
  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
Q

ih a healthy human brain, striatum cells fire when…

A

a drop of glutamate arrives

82
Q

4 symptoms of parkinsons

A
  1. mood - emotionally flat
  2. bradykinesia (HYPOKINESIA)
  3. tremor at rest (‘pill-rolling’)
  4. rigidity
83
Q

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 ________.

A

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.