The Brain Flashcards

1
Q

What is a tract ?

A

A fibre pathway passing through the CNS carrying a specific modality.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the function of the brainstem ?

A
  • Its a pathway for fibre tracts between higher and lower centres
  • Involved in controlling basic body functions such as breathing and heart rate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What reflex is the superior colliculi involved with ?

A

Visual reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What reflex is the inferior colliculi involved with ?

A

Auditory reflex

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which fissure separates the temporal and frontal/parietal lobes ?

A

Lateral fissure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Which sulcus separates the frontal and parietal lobes ?

A

Central sulcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which sulcus separates the occipital and parietal lobes ?

A

Parieto-occipital sulcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Where does the cerebellum get information from ?

A
  • Vestibular nuclei
  • Proprioceptors in limbs
  • Cerebrum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What makes up the Diencephalon ?

A
  • Thalamus
  • Hypothalamus
  • Pineal gland
  • Pituitary gland
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the main function of the Thalamus ?

A

It is a sensory relay centre

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What structure separates the Thalamus and Hypothalamus ?

A

The hypothalamic sulcus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the basal ganglia ?

A

Collection of neuronal cell bodies buried in the white matter of the brain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is hemispatial neglect ?

A

A deficit in attention and awareness to one side of the field of vision. Cause by damage to one hemisphere of the brain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What causes right-left agnosia (confusion) ?

A

A lesion to the dominant parietal lobe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is Aphasia ?

A

It affects the production or comprehension of speech and the ability to read or write.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens when a person has Broca’s Aphasia ?

A

They are able to understand speech but cannot or struggle to speak.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens when a person has Wernicke’s Aphasia ?

A

The can’t speak but struggle to understand what someone else says. They may not make sense.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What do commisural fibres connect ?

A

They connect corresponding areas of the two hemispheres e.g. the Corpus Callosum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What do association fibres connect ?

A

Different areas of the same hemisphere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What do projection fibres connect ?

A

The cortex and subcortical regions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What makes up the basal ganglia ?

A
  • Caudate Nucleus
  • Putamen
  • Globus Pallidus
  • Substantia Nigra
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the input regions of the basal ganglia ?

A

The Caudate Nucleus and the Putamen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are the output regions of the basal ganglia ?

A

The Globus Pallidus and Substantia Nigra

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Where does the Globus Pallidus project to ?

A

Thalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the role of the Basal Ganglia ?

A

To help initiate and regulate movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Definition of Cognition

A

The integration of sensory information to make sense of a situation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What role does the hippocampus have in memory ?

A

Memory formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What role does the amygdala have in memory ?

A

Puts an emotive feeling on a memory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What role does the thalamus have in memory ?

A

It finds the memory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What role does the cortex have in memory ?

A

It stores the memory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What makes up the limbic system ?

A

Amygdala
Hypothalamus
Cingulate gyrus
Hippocampus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What determines the significance of an event ?

A

Frontal cortex and the limbic system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is sensory memory ?

A

Memory of what happened seconds ago e.g. visual memory (< 1s) and auditory memory (< 4s).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is short-term memory ?

A

Compromises daily tasks, your working memory. Last seconds to hours.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is you immediate long-term memory ?

A

What you did last weekend, hours to weeks ago. its associated with changes in the chemical activity within synapses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is your long term memory ?

A

Where you lived as a child, who your friends were. Associated with structural changes in synapses.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is short term memory dependent on ?

A

Reverberating circuits

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What happens when a short term memory is deemed significant ?

A

Leaves the reverberating circuit and is stored in long-term memory.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Definition of Amnesia

A

Memory loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is Anterograde Amnesia ?

A

Can’t form new memories

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is Retrograde Amnesia ?

A

Can’t remember newer old memories

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What is explicit long-term memory ?

A

Abstract memory from events. It involves the hippocampus.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is procedural long-term memory ?

A

Through repetition its acquired slowly. Doesn’t involve the hippocampus, it is mainly based in the cerebellum.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What is the name of the circuit that occurs in the limbic system ?

A

Papez circuit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Describe the Papez circuit

A

Cortex - Thalamus - Cingulate gyrus - Hippocampus - Mamillary body - Cortex or Thalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Which neurones are needed for REM sleep ?

A

Cholinergic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What do people with Alzheimers not have a lot of ?

A

REM sleep - little memory consolidation occurs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

How is CSF formed ?

A

Sodium is pumped into the ventricles and water follows down an osmotic gradient from blood vessels.

49
Q

What foramen/foramina in the 4th ventricle does the CSF flow out of ?

A

The foramina of Luschka

The foramen of Magendie

50
Q

Why and how does absorption of CSF occur ?

A

The H20 pressure is 3-5 cm higher in the subarachnoid space than in the subdural venous sinuses. Absorption occurs down a pressure gradient moving through arachnoid villi which open their valves.

51
Q

What are the 2 types of hydrocephalus ?

A

Communicating and Non-Communicating

52
Q

Features of CoH

A
  • Cause an increase in ICP
  • Usually due to the fact that production of CSF > reabsorption
  • Patient gets a headache, loses consciousness, N/V, papilloedema and can’t look up
  • Can be due to an infection/haemorrhage/post-operation
53
Q

Features of NCoH

A
  • Blockage in the pipeline
  • Can be due to tumours, cysts, trauma, infection and congenital malformations.
  • Can vary in how quickly symptoms progressive
54
Q

How would you investigate Hydrocephalus ?

A
  • X-Ray and use Evans ratio

- CT/MRI

55
Q

What is the treatment for Hydrocephalus ?

A
  • External ventricular drain
  • Ventriculo-peritoneal shunt
  • 3rd Ventriculostomy
56
Q

What type of Hydrocephalus can cause Dementia ?

A

Normal pressure Hydrocephalus

57
Q

How does a patient with Dementia present second to Hydrocephalus ?

A

Wet, wobble and wacky

  • Incontinence
  • Wobble
  • Cognitive function declining
58
Q

How would you investigate and what results would come back with Dementia present second to Hydrocephalus ?

A
  • CT shows signs of communicating hydrocephalus
  • LP normal pressure
  • Symptoms resolve after drainage
59
Q

What are the contraindications for LP ?

A
  • If patient is unstable
  • If there is increased ICP
  • Possible abscess
  • Bleeding disorder
  • Chairhi malformations
60
Q

What are Chairhi malformations ?

A

Part of the cerebellum herniates into the foramen magnum and into the spinal canal.

61
Q

Steps for LP

A
  • Apply topical anaesthesia to sight around 30-45 beforehead
  • Use iodine solution to clean 10cm around insertion sight
  • Drape the site with fenestrated drape
  • With the bevel up insert largest atraumatic needle possible based on clinical judgment. Push inwards towards umbilicus.
  • Pop indicates ligamentum flavum and dura have been punctured, remove stylet and check flow
  • Attach manometer to get an opening pressure
62
Q

When you are collecting samples for LP how many do you collect and what for ?

A
  • 3 samples

- Cell count, culture and glucose

63
Q

What are the possible complications of LP ?

A
  • Nerve trauma
  • Infection
  • Bleeding
  • Disk herniation
64
Q

What is the most common side effect of a LP ?

A

A spinal headache, it occurs due to the arachnoid being pulled through into the dura.

65
Q

What is the treatment for spinal headache ?

A
  • Bed rest
  • Hydration
  • Epidural blood patch
  • Caffeine
66
Q

What is the Munro-Kelly Doctrine ?

A

The skull is a fixed box filled with brain, blood and CSF. A change in the volume of one of these changes the overall balance/pressure. It must remain in equilibrium and therefore the volume of another must change.

67
Q

Definition of a stroke

A

A stroke is a sudden interruption in the blood supply of the brain.

68
Q

What are the three main causes of stroke ?

A
  1. Atheroma and thrombosis
  2. Thromboembolism
  3. Ruptured aneurysm
69
Q

What is a regional cerebral infarct ?

A

Localised area of brain death, goes soft then cystic

70
Q

What two things cause aneurysms to form ?

A
  1. Hypertension

2. Weakened vessel walls

71
Q

What might happen to distal tissue as a result of an aneurysm ?

A

Vessel may spasm and so lack of blood gets to distal tissue. Further infarcts occur.

72
Q

What two things may reduce blood flow through brain ?

A
  1. Hypotension

2. Brain swelling

73
Q

What two things reduce oxygen supply in the blood ?

A
  1. CO2 poisoning

2. Near drowning

74
Q

What are watershed infarcts ?

A

Zones of infarction at the interface between artery perfusion sites. Seen with hypotension.

75
Q

Define laminar infarction

A

Lines of necrosis and thinning

76
Q

What condition prevents lack of blood flow and oxygen to brain ?

A

Cardiac arrest

77
Q

What perfusion level does ischaemia occur at ?

A

20ml/g/min

78
Q

What perfusion level does infarction occur at ?

A

10g/ml/min

79
Q

What is the equation for Cerebral Perfusion Pressure (CPP) ?

A

CPP = MAP - ICP

80
Q

How do you calculate MAP ?

A

MAP = DP + 1/3PP

81
Q

What effect does an increase in CPP have ?

A

An increase in ICP causes the CPP to decrease.

82
Q

Define cerebral auto regulation

A

The ability to maintain a constant blood flow over a wide range of CPP (50-150mmHg).

83
Q

What happens when CPP is low ?

A

The arterioles dilate to reduce resistance to blood flow.

84
Q

What happens when CPP is high ?

A

The arterioles constrict to increase resistance to blood flow.

85
Q

What happens if ICP increases above 150mmHg ?

A

The auto regulatory system fails

86
Q

What is Vasogenic Oedema ?

A

Exudation of fluid from the vascular system

87
Q

What two things can inhibit cerebral auto regulation ?

A
  • Head trauma

- Toxins e.g. CO2

88
Q

Define cerebral oedema

A

Increase in brain volume as a result of an increase in water content.

89
Q

Define compliance

A

Change in volume observed for a given change in pressure. Results in less blood and CSF in the skull.

90
Q

What is the equation for compliance ?

A

dV/dP

91
Q

Define elastance

A

Change in pressure observed for a change in volume. Results in outward expansion of the cranial walls.

92
Q

What is the equation for elastance ?

A

dP/dV

93
Q

When looking at ICP waveforms, what does P1 show ?

A

Arterial pulse

94
Q

When looking at ICP waveforms, what does P2 show ?

A

Cerebral compliance

95
Q

What are Lundberg waves ?

A

Show how ICP changed due to cerebral autoregulation

96
Q

What is the Cushing’s reflex ?

A

As CBF decreases sympathetic response is activated, this results in tachycardia and hypertension to increase blood flow. Baroreceptors in the carotid artery detect this and stimulate the vagus nerve which triggers bradycardia.

Respiratory cycles continuously change in response to ICP.

97
Q

How do you manage patients with an increased ICP ?

A
  • Mannitol
  • Surgery - hemicraniectomy/external ventricular drainage
  • Raise head
  • Hyperventilation for acute resolution
98
Q

What are the two newer concepts in management of raise ICP ?

A
  • Brain tissue oxygen monitoring

- Micro-dialysis

99
Q

Why is cognitive functions assessed ? (3)

A
  • Diagnosis
  • Prognosis
  • Treatment
100
Q

Define post-traumatic amnesia

A

Period of recovery following traumatic brain injury the patient is unable to locate themselves in time and space and cannot remember events that have occurred since the incident.

101
Q

How is cognition assessed via bedside ? (£)

A
  1. Observation
  2. Clinical interview
  3. Screening assessments
102
Q

Name the 3 screening assessments commonly used

A
  1. MOCA
  2. ACE III
  3. Cognitive assessment for clinicians
103
Q

Name some of the main areas of cognitive function

A
Thinking 
Learning 
Memory 
Attention
Reasoning
Problem solving
104
Q

What 4 assessment considerations should be made ?

A
  1. Environment
  2. Physical factors e.g. fatigue
  3. Psychological factors e.g. mood and confidence
  4. Pre-accident factors e.g. education/occupation
105
Q

What is the name of the fissure separating the anterior and posterior lobes of the cerebellum ?

A

Primary fissure

106
Q

What is the name of the fissure separating the anterior and flocculonodular lobes

A

Posterolateral fissure

107
Q

What affect does GABA have ?

A

Slow down the brain messages - it is a neurotransmitter

108
Q

What affect does glutamate have ?

A

Increases brain activity - it is a neurotransmitter

109
Q

What is Ach ?

A

It is a neuromodulator and helps us decide whether to respond to a signal or not

110
Q

What condition can lack of Ach lead to ?

A

Alzheimers

111
Q

What type of channels are muscarinic channels ?

A

G protein channels

112
Q

What type of channels are nicotinic channels ?

A

Ion channels

113
Q

What is noradrenaline ?

A

A neuromodulator and keeps the brain on high alert

114
Q

What is dopamine ?

A

It is involved in punishment and rewards but also movement

115
Q

What does serotonin do ?

A

Depresses bad thoughts and helps you sleep

116
Q

What functions does histamine have in the CNS ?

A

It keeps you awake and warm

117
Q

Where is melatonin produced ?

A

Pineal gland

118
Q

What does melatonin do ?

A

Makes you sleepy

119
Q

What does orexin do ?

A

Keeps you awake