Neurology Flashcards

(185 cards)

1
Q

Name the meninges in order

A

Dura mater
Arachnoid mater
Pia mater

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

Which meninge has two layers which surround the venous sinuses?

A

Dura mater

Has a periosteal layer and a meningeal layer.

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

Which meninge contains the cerebrospinal fluid?

A

Arachnoid mater

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

Which meninge is tightly bound to the surface of the brain?

A

Pia mater

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

Which fascial layers divide the brain into sections? What is their function? What are they made of ?

A

Falx cerebri
Tentorium cerebelli

Prevent brain rotating within the skull

Made of reflections of dura mater

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

Which bony ridge does the falx cerebri attach onto?

A

Crista Galli of ethmoid

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

What is the blood supply to the scalp?

A

Aponeurosis of superficial temporal arteries and occipital arteries

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

Why does the scalp bleed so heavily? Why does the bone underneath not suffer from necrosis?

A

It is an Aponeurosis direct from external carotid.
The vessels can’t constrict because they are tightly bound to connective tissue

Bone underneath supplied by middle meningeal arteries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What type of bleed from which vessel usually causes an extradural haematoma?

A

Forceful arterial - usually middle meningeal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What type of bleed from which vessel usually causes an subdural haematoma?

A

Venous - veins between brain and venous sinuses

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

What type of patient is particular risk factor for a subdural haematoma?

A

Elderly with dementia.

Brain atrophies leaving longer sections of veins to sinuses exposed. Smaller brain also means more rotation in the cranial cavity so greater shearing forces.

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

How would you identify a sub arachnoid haemorrhage?

A

Pinkish CSF

Mri covered in white

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

Give 3 functions of cerebrospinal fluid.

A

Buoyancy and reduced weight
Homeostasis
Mechanical protection

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

How is CSF produced?

A

Choroid plexus in the lateral ventricles filters blood

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

Describe the flow of cerebrospinal fluid through the nervous system.

A

Produced in lateral ventricles - foramen of monro - 3rd ventricle - cerebral aqueduct - 4th ventricle

Then either - spinal canal or medial and lateral apertures to sub arachnoid space

Drains back to venous sinuses through arachnoid villi

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

What does a yellowish CSF indicate?

A

Infection eg meningitis

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

Which bacteria are implicated in meningitis?

A

Streptococcus pneumoniae
Or
Neisseria meningitidis

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

Why is meningitis so dangerous?

A

Inflammation and oedema raises intracranial pressure

Risk of decreased perfusion and/or cranial herniation (coning)

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

Give 4 key diagnostic symptoms of meningitis other than fever and headache.

A

Photophobia
Confusion
Stiff neck
(Later) rash due to sepsis

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

In which condition is congenital hydrocephalus common? Why?

A

Spina bifida
Notochord does not close properly so ventricles not complete.
Struggle to maintain pressure of CSF so excess is produced

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

Name the layers of the scalp

A
Skin
Connective tissue
Aponeurosis
Loose connective tissue
Periosteum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What are the 3 main arteries which are supplied by the circle of Willis?

A

Anterior middle and posterior cerebral arteries

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

Which areas of the brain are supplied by the anterior, middle and posterior cerebral arteries?

A

Anterior - medial full thickness strip, as far back as the occipital lobe
Middle - most of parietal and temporal lobes
Posterior - occipital lobe and inferior temporal lobe

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

Give 3 key functions of the frontal lobe

A

Executive function
Decision making
Motor function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Give 3 key functions of the parietal lobe
Somatosensory Spatial awareness and perception Broca's speech
26
Give the key function of the occipital lobe
Primary visual cortex
27
Give 3 key functions of the temporal lobe
Wernicke's - language Hearing Memory - hippocampus
28
What are the 3 main arteries that supply the brain?
``` 2 internal carotids Vertebral artery (-basilar) ```
29
What do the external carotids supply?
Facial Maxillary - middle meningeal (skull and meninges) Superficial temporal - (scalp)
30
Where is the carotid sinus located? What is its clinical significance? What is its nerve supply?
Bifurcation of the common carotid Location of baroreptors Innervated by Glossopharyngeal
31
Where is atheroma build up common in the head and neck? Why?
Carotid sinus due to turbulent flow of blood
32
Where are intracerebral aneurysms most common? Why are they dangerous?
Circle of Willis | Risk of rupture
33
Give 4 broad causes of stroke
Thrombus Embolus eg from carotid thrombus Hypoperfusion eg in shock Haemorrhage/ haematoma causing hypoperfusion and pressure necrosis
34
Which vein is used to measure jugular venous pressure (JVP)? Why?
Internal jugular vein Drains closest to right atrium and pulsatile due to valve in inferior bulb. Pulsation level gives good approximation of right atrial pressure
35
Where do the dural venous sinuses drain to?
Internal jugular vein
36
Where does blood from the scalp and face drain to?
Follows arteries to internal and external jugular veins
37
Which 2 disorders are caused by the failure of the notochord to fuse?
Cranially - anencephaly | Caudally - spina bifida
38
How can incidence of spina bifida be reduced?
Folic acid taken prior to conception and during the first trimester
39
How is the cauda equina formed?
Vertebral column grows faster than the spinal cord. The nerve roots below L1 are forced to extend.
40
What is cauda equina syndrome? How is it caused?
Trauma to L3/L4 affects S3-S5 dermatomes because the roots of these dermatomes start higher up. Leads to saddle anaesthesia Caused by trauma eg epidural or lumbar puncture.
41
Where is the correct site of a lumbar puncture? Why?
L3-L5 because it is below the end of the spinal cord
42
What causes the sulci and gyri of the brain?
Growth within the fixed cranial cavity
43
What is the prosencephalon? What are its derivatives?
Forebrain Telencephalon - cortex Diencephalon - thalamus
44
What is the mesencephalon? What are its derivatives?
Midbrain - midbrain stuctures
45
What is the rhombencephalon? What are its derivatives?
Metencephalon - pons and cerebellum | Myelencephalon - medulla
46
Where do neural crest cells arise? How are they formed?
Cells that arise on the lateral border of the neural tube. | Formed by epithelial to mesenchyme transition.
47
What are the derivatives of neural crest cells?
Lots of types of specialised cells | Eg Schwann, glia, ganglia, melanocytes, smooth muscle etc
48
Which types of embryological cells are most sensitive to alcohol?
Neurectoderm - particularly neural crest cells
49
What are the derivatives of the 1st pharyngeal arch?
``` Nerve - trigeminal Cartilage - mandible Artery - none Pouch - auditory canal Cleft - tympanic membrane ```
50
What are the derivatives of the 2nd pharyngeal arch?
``` Nerve - facial Cartilage - stapes, styloid, hyoid Artery - none Pouch - palatine tonsils Cleft - none ```
51
What are the derivatives of the 3rd pharyngeal arch?
``` Nerve - Glossopharyngeal Cartilage - none Artery - internal carotid Pouch - thymus and parathyroid Cleft - none ```
52
What are the derivatives of the 4th pharyngeal arch?
``` Nerve - vagus (superior laryngeal) Cartilage - epiglottis, thyroid, cricoid Artery - aortic arch, brachiocephalic, subclavian Pouch - thyroid gland Cleft - none ```
53
What are the derivatives of the 6th pharyngeal arch?
``` Nerve - Vagus (recurrent laryngeal) Cartilage - arytenoid Artery - pulmonary arteries Pouch - none Cleft - none ```
54
What is the path of the recurrent laryngeal nerve on the left and right? Why is it like this?
Forms from the 6th arch so has to loop around the 4th arch to get where it wants On the right that is just the subclavian artery On the left that is the arch of the aorta and the ductus arteriosus
55
How does the oral cavity develop embryologically?
Stomatadeum contains buccopharyngeal membrane | No mesoderm so obliterated
56
How does the nose develop embryologically?
Nasal placodes in the frontonasal prominence grow into pits. They are pushed medially by the growth of the maxillary prominence below. The nasal septum grows down to join the palate
57
How does the palate develop embryologically?
Fusion of nasal pits in frontonasal prominence forms primary palate - philtrum, four incisors and lip. Maxillary palatal shelves from 1st arch grow into midline to form secondary palate. All fuse
58
How do the eyes develop embryologically?
Outgrowth of diencephalon on side of head | Pushed medially by growth of facial prominences
59
How do the ears develop embryologically?
Auditory canal develops in 1st cleft in neck Auricle grow from 2nd arch All pushed up and in by growth of mandible
60
What is the cause of a cleft lip / palate?
Lip - failure of primary and secondary palate to fuse together Palate - as above plus the failure of palatal shelves to meet in midline
61
What are the anterior and posterior pituitary gland derived from?
Anterior - rathke's pouch - pinched off ectoderm | Posterior - infundibulum - pinched off neuroectoderm
62
Where does the thyroid originally develop? Where does it descend to? What is the clinical significance of this?
Foramen cecum at 2nd arch To level of 4th arch Can leave ectopic thyroid behind
63
What is the function of the dorsal column?
Fine touch, vibration and conscious proprioception
64
Where does the dorsal column decussate?
Medulla oblongata
65
Where are the cell bodies of the 1st, 2nd and 3rd order neurons of the dorsal column?
1st - dorsal root ganglion 2nd - nucleus cuneatus/ gracilis 3rd - thalamus
66
Where are the cell bodies of the 1st, 2nd and 3rd order neurons of the spinothalamic tract?
1st - dorsal root ganglion 2nd - dorsal horn 3rd - thalamus
67
Where does the spinothalamic tract decussate?
Spinal cord
68
What is the function of the spinothalamic tract?
Crude touch Pressure Pain and temperature
69
What is the function of the spinocerebellar tract?
Unconscious proprioception
70
Why is some sensory information unconscious?
Some proprioception is unconscious because it travels through the spinocerebellar tract and avoids the cortex.
71
What symptom would be associated with damage to the dorsal column? Give two possible causes.
Loss of conscious proprioception - ataxic gait | Vitamin B12 deficiency, neurosyphilis
72
What symptom would be associated with damage to the spinothalamic tract? Give a possible cause.
Loss of pain sensation | Syringomyelia - swelling of spinal canal pushes on spinothalamic where it decussates. Affects bilaterally.
73
What is the name given to the pattern of sensory loss in peripheral neuropathy? Give two possible causes.
Glove and stocking Diabetic neuropathy Guillain barre syndrome
74
What is Brown-Sequard syndrome?
Traumatic hemi section of spinal cord Causes ipsilateral loss of dorsal column (fine touch) Contralateral loss of spinothalamic (pain and temperature)
74
Which neuron in the sensory pathway is damaged in a peripheral neuropathy?
1st order
75
What is referred pain?
Pain felt in a site incongruous with the site of damage. | Caused by visceral sensory afferents hijacking the somatosensory afferents at a particular spinal level.
78
What is the function of the corticospinal tract?
Voluntary movements of the body via upper motor neuron moderation.
79
Where are the cell bodies of the upper motor neurons of the corticospinal tract?
Ventral horn of spinal cord
81
What is the function of the extrapyramidal descending tracts? Can you name them?
``` Involuntary muscle tone Vestibulospinal Reticulospinal Rubrospinal Tectospinal ```
82
What is the name of the white matter tract that the descending tracts pass through before they reach the medulla? Why is it clinically important?
Internal capsule | Particularly susceptible to haemorrhagic stroke
83
What is the function of the corticobulbar tract?
Voluntary movements of the head and neck via upper motor neuron moderation.
84
Where does the corticobulbar tract decussate? What is special about the way it decussates?
Medulla It is mostly bilateral except contralateral in the lower face, and the tongue (where it synapses with the facial and hypoglossal nerves)
85
Where does the corticospinal tract decussate?
``` Lateral tract (most) - medullary pyramids Anterior (some lastminute.com ) - spinal cord ```
86
What is a Monosynaptic reflex arc? Give an example
Signal straight from a first order sensory neuron which detects stretch in a muscle to a lower motor neuron which contracts the muscle. Stretch reflex
87
What is a polysynaptic reflex arc? Give an example.
A reflex signal that is sent via an interneuron. Withdrawal reflex in response to pain or the antagonist inhibition arc that pairs with any reflex.
88
What are the 5 components of a reflex?
1. Receptor 2. Afferent nerve 3. Integrating centre 4. Efferent nerve 5. Effector organ
89
Where does a 1st order sensory neuron synapse? (Four places)
2nd order sensory in dorsal column (nucleus gracilis/cuneatus) 2nd order sensory in spinothalamic tract (dorsal horn) Lower motor neuron for monosynaptic reflex arc Interneuron for polysynaptic reflex arc
90
How does an upper motor neuron control movement of the muscles? What is the exception?
Through inhibiting the lower motor neuron which is constantly excited by reflex action. Except in the hands where there is also ability to excite the lower motor neurons which allows for increased dexterity.
91
Give four key signs of upper motor neuron injury.
Hyperreflexia Hypertonia/ spastic weakness Clonus (muscle spasm following stretch) Babinski's sign (foot scrape, toe flare)
92
Give 3 key signs of lower motor neuron injury.
Hyporeflexia Hypotonia / flaccid weakness Fasciculations
93
What causes clonus?
Stretch reflex stimulated in the ankle. Upper motor neuron injured so unable to inhibit the reflex. Results in spasm due to the differing lengths of time for the monosynaptic reflex and the polysynaptic antagonist muscle reflex to reach the muscles.
94
How would you distinguish between visceral and somatic pain in a history?
Somatic - sharp, stabbing, burning. Can be pinpointed. | Visceral - dull, aching, hard to pinpoint
95
Why might you 'see Stars' if punched in the eye?
Receptors for vision (like all receptors) are modality specific only to a point. If overwhelmed by input, they can be forced to fire by touch/pain sensation.
96
Where are most sensory receptors located? What implication does this have for burns?
In the dermis Loss of sensation occurs only in full thickness burns
97
Why can't you feel your clothes on your skin unless you attend to them?
Phasic receptors rapidly adapt to a constant stimulus. They fire when there is a change to the stimulus. Opposite is tonic receptors which fire continuously throughout stimulus
98
Where on your body is there most sensory acuity? Where is it the weakest? How can it be measured?
Fingertips and lips vs Trunk 2 point discrimination with a paper clip
99
What causes an increase in sensory acuity in different areas of the body?
Smaller receptive fields, increased lateral inhibition
100
What causes an increase in motor dexterity in different areas of the body?
Smaller motor units
101
What causes shingles? What are the symptoms?
Dormant herpes zoster (chicken pox) in the dorsal root ganglion re emerges. Pain - burning Rash - scaly Parasthesia All restricted to a dermatome
102
What is meant by orderly recruitment of motor units? Give two reasons that it is beneficial.
Motor units are recruited in order of increasing size so that when only a small force is required, the small ones are activated. As a bigger force is required, more and more bigger units are activated. 1. Prevents fatigue by saving the big fatiguable units till needed. 2. Permits fine control by only using small units with small forces.
103
Give 5 extrapyramidal signs. Damage to which structure would cause these?
Pseudoparkinsonism - tremor, bradykinesia, masked facies, shuffling gait Tardive dyskinesia - jerky ticks Basal ganglia
104
Give 2 cerebellar signs.
Ataxia | Intention tremor
105
What are the 5 cardinal features of Parkinson's disease?
``` Pill rolling tremor Shuffling (festinating gait) Masked facies Cog wheel rigidity Bradykinesia ```
106
Name 5 diseases/disorders which might cause lower motor neuron signs.
``` Trauma Primary myopathy - eg muscular dystrophy Guillain Barre Polio Myasthenia gravis ```
107
Name 5 diseases/disorders which might cause upper motor neuron signs.
``` Motor neuron disease - upper and lower Multiple sclerosis Parkinson's Huntington's Stroke ```
108
What are the functions of the basal ganglia in motor control?
Decision to move Direction of movement Magnitude of movement Facial expression
109
What is the difference between alpha and gamma motor neurons?
Alpha cause the contraction of the muscle Gamma control the size of the muscle spindle receptor so that it remains at the right length to detect stretch. This maintains tone and readiness for action.
110
What causes Parkinson's ?
Degeneration of the dopaminergic neurons in the direct nigrostriatal pathway. Leads to extrapyramidal signs.
111
What causes Huntington's?
Degeneration of the GABA neurons in the indirect nigrostriatal pathway. Leads to specific extrapyramidal signs.
112
What causes multiple sclerosis?
Autoimmune demyelination of the axons in both upper and lower motor neurons. Sensation is unaffected.
113
What causes polio?
Viral infection that causes irreversible demyelination of the lower motor neuron and loss of movement. Sensation is unaffected.
114
What is Guillain Barre syndrome?
Rapid onset autoimmune destruction of lower motor neurons which is triggered by - previous infection.
115
What are the key symptoms of Huntingtons?
Chorea - continuous muscle twitching | Mood and behavioural change
116
Why can't you give L-Dopa for Huntingtons? Why does it eventually stop working in Parkinson's?
Huntingtons affects the GABA neurons in the nigrostriatal pathway so extra dopamine will have no effect In Parkinson's extra dopamine will help for a while until there is so much degeneration that there are not enough neurons to cope with the extra neurotransmitter.
117
When an tissue damage occurs, what substances are released to stimulate pain fibres?
Prostaglandins, K+, bradykinin
118
How does a nociceptor respond to prostaglandins, bradykinin etc?
Action potential along pain fibres (A delta and C) Also releases substance P which stimulates mast cells to release histamine
119
Which nerve fibre types are associated with pain?
A delta | C
120
Name the nerve fibre types present in a mixed nerve in order of sensitivity. Also give their function.
``` A alpha - motor A beta - proprioception A gamma - pressure A delta - pain B - autonomic C - pain ```
121
In carpal tunnel syndrome, why is motor function lost first, then numbness and tingling before pain?
Function lost in order of the sensitivity of fibre types. From A alpha down to C fibres.
122
What makes A fibres more sensitive than C fibres?
Larger diameter | Myelinated
123
What is the cause of referred pain?
Visceral sensory fibres synapse with the same 2nd order neuron as a set of somatic fibres in the dorsal horn. The pain is interpreted as coming from that somatic dermatome.
124
Where precisely do nociceptive fibres synapse onto second order neurons in the spinothalamic tract?
Laminae 1, 2 and 5 of the dorsal horn
125
What is lamina 2 of the dorsal horn otherwise known as?
Substantia gelatinosa
126
Which lamina in the dorsal horn modulates pain signals by inhibiting the others?
Lamina 2 - substantia gelatinosa
127
Where do opioids act?
Opioid (mu) receptors in the substantia gelatinosa as well as many other areas in the nervous system. Stimulate the substantia gelatinosa to dampen pain signals.
128
Give 2 natural opioids and 2 drug opioids. Can you think of an antagonist for these drugs?
Natural - endorphins, enkephalins Drugs - morphine, codeine Antagonist - naloxone
129
Why does rubbing a pain and taking a hot bath ease it?
Thermoreceptors and mechanoreceptors stimulate the substantia gelatinosa to inhibit pain signals
130
What is hyperalgesia?
An increased sensation of pain to a mild pain stimulus. | Hypersensitivity.
131
What is allodynia? Can you give an example?
A sensation of pain from something that is not normally painful. Thigh pain in an arthritic knee
132
What is the cause of wind-up in chronic pain?
Persistent activation leads to up regulation and an increase in number of receptors at the synapse. This causes an increase in sensitivity and a larger receptive field.
133
What is neuropathic pain described as?
Burning, tingling, parasthesia, shooting
134
What is the cause of phantom limb pain?
Cortical remodelling
135
Where do most strokes occur and why?
Middle cerebral artery because there is a lack of collateral supply
136
What is a stroke? How is it different from a TIA?
Abrupt loss of focal function from infarct or haemorrhage. | TIA is over in 24 hours. Stroke symptoms last over 24 hours.
137
What is the pathophysiology of a haemorrhagic transformation infarct stroke?
Infarct - inflammation - oedema - burst vessel - bleed | Stroke with both infarct and haemorrhagic features.
138
Name 4 modifiable risk factors for stroke.
Smoking /Alcohol Hypertension Hyperglycaemia Atherosclerosis
139
Name 4 non modifiable risk factors for stroke
Age Aneurysm Blood disorder Cardiac - Atrial fibrillation, Patent foramen ovale
140
What signs suggest a stroke is haemorrhagic rather than an infarct?
Raised intracranial pressure (vomiting, drowsy, headache) Raised INR Patient on warfarin or has blood disorder Young patient Head CT - midline shift and white blood
141
How do you differentiate between a stroke on the dominant and non dominant sides?
Dominant - dysgraphia, dyslexia, dysphasia | Non dominant - complete visuospatial neglect
142
What are the symptoms of a frontal lobe stroke?
Motor deficit Personality change Brocas non fluent aphasia
143
What are the symptoms of a parietal lobe stroke?
Dominant neglect | Sensory deficits
144
What are the symptoms of a temporal lobe stroke?
Auditory deficits Memory problems Wernickes fluent aphasia
145
What are the symptoms of a POCS stroke?
Posterior circulation Occipital/cerebellar signs - Visual disturbance, balance, coordination, cranial nerve nuclei.
146
What are the symptoms of a TACS stroke?
Total anterior circulation (Proximal MCA or ICA) Hemiparesis Hemianopia Other cerebral dysfunction according to lobe
147
What are the symptoms of a PACS stroke?
Partial anterior circulation (MCA) 2 of 3 Hemiparesis Hemianopia Cerebral dysfunction
148
What are the symptoms of a LACS stroke?
Lacunar (Single perforating artery) Silent
149
Why is it important to order an ecg for a suspected stroke?
Find out if cardiac problems eg af which highly increase the likelihood of a repeat.
150
Why is it important to test the bm of a suspected stroke?
Hypoglycaemic attack is a huge differential
151
In ageing which sound frequencies are lost first?
High frequencies
152
What is meant by tonotopy in the ear?
Describes the mechanical tuning of the ear to different frequencies. The position along the basement membrane of the cochlea determines the resonant frequency. The hair cells along the membrane therefore respond more readily to different frequencies.
153
Describe the detection of sound in the cochlea on a molecular level.
Stereo cilia bend. K channels open - depolarise the cell due to abnormal gradient (endolymph has high k). Ca channels open. Neurotransmitter release to spiral ganglia.
154
What features of an action potential along auditory neurons determine the volume of the sound.
Frequency of action potentials | Size of action potentials due to recruitment of nearby fibres.
155
Describe the auditory pathway.
Outer hair cells - inner hair cells - spiral ganglion - superior olivary - inferior colliculis - medial geniculate nucleus of thalamus - auditory cortex in temporal lobe
156
What are the results of rinne and webers test in conductive hearing loss?
Weber - louder on damaged side | Rinne - negative (abnormal) louder through mastoid process
157
What are the results of rinne and webers test in sensorineural hearing loss?
Weber - louder on opposite side Rinne - positive test - or appears normal because complete deafness.
158
What is meant by a positive rinne test?
Normal result. (Opposite to every other test!!!)
159
What type of bleed from which vessel usually causes a subarachnoid haematoma?
Arterial from a burst aneurysm
160
Give some potential causes of fitting.
Brain disease - stroke, space occupying lesion Metabolic - hypoglycaemia, low ca, low Na, high urea Infection - febrile convulsions Drug induced Idiosyncratic- (>2 epilepsy)
161
What is status epilepticus? Why is it an emergency?
Fitting for over 30mins or a cluster of fits with no recovery Increases metabolic demand of the brain - brain damage or death
162
What is a partial seizure? Does a patient lose consciousness?
Partial = focal Symptoms reflect area which is overactive. Eg motor, aura, Jamais/déjà vu. Simple - conscious Complex - loss of consciousness
163
What is a generalised seizure? Does the patient lose consciousness?
Spread throughout the brain with a loss of consciousness Can include tonic clonic as well as absence seizures
164
What are cortical association areas?
Areas in the cortex where information from different modalities is brought together for processing
165
Which cortical functions are lateralised to the left hemisphere?
Language Logic Maths Motor skills
166
Which cortical functions are lateralised to the right hemisphere?
Emotional processing Visuospatial Art Music
167
Which hemisphere is dominant in 95% of people?
Left
168
Describe the neural pathway of speaking a written word.
``` Primary visual cortex Angular gyrus Wernickes area Arcuate fasciculus Broca's area Motor cortex ```
169
Describe the neural pathway of speaking a heard word.
``` Primary auditory cortex Wernickes area Arcuate fasciculus Broca's area Motor cortex ```
170
What is the proper name for an expressive, non- fluent aphasia?
Broca's | Can't get words out but full understanding and can comply with complex commands
171
What is the name for a receptive, fluent aphasia?
Wernickes | Non sensical fluent speech. Can't comply with complex commands.
172
What is long term potentiation? Which neurotransmitter is involved?
Description of memory formation | Hippocampus signals for NMDA glutamate receptors to upregulate synapses and neurotransmitter release.
173
What factors can increase the likelihood of a memory making it to the long term?
Rehearsal Emotion Association
174
What is anterograde amnesia? What brain lesion is it associated with?
Failure to form new memories | Hippocampus
175
What is retrograde amnesia? What brain lesion is it associated with?
Can't retrieve old memories | Global atrophy eg Alzheimer's
176
What brain pathway controls wakefulness? What occurs when it is active? What happens when it is quiet?
Ascending reticular activating system (ARAS) Activated - awake or rem sleep Quiet - slow wave, deep sleep
177
What sleep difficulties are associated with anxiety? How is this different from depression?
Anxiety - difficult getting to sleep | Depression - waking in the night then difficult getting back to sleep
178
What biological functions occur during deep slow wave sleep?
Rest Decrease basal metabolic rate Endocrine secretion
179
What biological functions occur during rem sleep?
Memory formation without emotion | Raised basal metabolic rate
180
Which neurotransmitter remains active during rem sleep?
Ach
181
Give three types of tremor and their associated disorder.
Pill rolling at rest - Parkinson's Intention - cerebellar damage Idiopathic
182
What is the difference between communicating and non- communicating hydrocephalus?
Communicating - Flow of CSF is uninterrupted. Build up is due to problem with the arachnoid villi Non- communicating- Flow is blocked. Most commonly at narrowest point which is cerebral aqueduct.
183
If there is an infection of the spinal cord, where will pus collect?
Posterior mediastinum The prevertebral fascia is the compartment that contains the spinal cord and it extends this far, through the retropharyngeal space
184
Which motor neurons are most important for eliciting motor tone?
Gamma because they are small so have a low threshold for action potential. So constant activity.
185
Which type of motor neurones are most important for eliciting action?
Alpha. The big chunky myelinated ones.
186
What are the signs of multiple sclerosis?
Upper motor neuron signs and sensory signs. But no lower motor neuron signs
187
What are the signs of motor neuron disease?
Upper and lower motor neuron mix. | No sensory signs.