Neuro Misc. Flashcards
What is Nissl substance
Rough endoplasmic reticulum
What are the two types of Golgi axons and what is the difference between them
Golgi type 1 - long axons
Golgi type 2 - short axons
Which cells produce myelin in the CNS and PSN respectively
CNS - oligodendrocytes
PNS - Schwann cells
What is the ratio of oligodendrocytes to axons they produce myelin for
1 oligodendrocyte covers many neurons
What is the ratio of Schwann cells to axons they produce myelin for
Many Schwann cells cover 1 neuron
The influx of which two ions cause depolarisation
Na+
Ca2+
The influx of which ion causes hyperpolarisation
Cl-
The efflux of which ion causes hyperpolarisation
K+
What do hyperpolarisation and depolarisation cause with regards to excitation and inhibition
Depolarisation –> excitation
Hyperpolarisation –> inhibition
Name the main excitatory neurotransmitter
Glutamate
Name the two main inhibitory neurotransmitters
GABA, Glycine
What is the distribution of GABA and Glycine neurons in the brain
GABA is widespread
Glycine mostly in brainstem and spinal cord
Name the 4 main types of sensory neuron
Aα
Aβ
Aδ
C
Which of the types of sensory neuron has the most myelination
Aα
A higher degree of myelination correlates to what speed of conduction
Fast conduction
What do Aα neurons perceive
Proprioception of skeletal muscle
What do Aβ neurons perceive
Skin mechanoreceptor information
What do Aδ neurons perceive
Pain and temperature
What do C neurons perceive
Pain, temperature and itch
Which corpuscle has a higher two-point discrimination value, Meissner’s or Pacinian
Meissner’s
Where do the DCML, Corticospinal and Spinothalamic tracts decussate
DCML at Medial Lemniscus
Spinothalamic at a segmental spinal level
Corticospinal - 85% at Medullary pyramids, 15% segmentally
What are the 4 Brodmann areas
1, 2, 3a, 3b
Define a “motor neurone pool”
All the alpha motor neurones which innervate a single muscle
Explain reciprocal inhibition using the hamstrings and quadriceps as an example
1a fibre supplying alpha motor neurone of quadriceps inhibits the alpha motor neurone of the hamstrings via inhibitory interneurons
What is the difference between ionotropic and metabotropic receptors
Ionotropic - direct, rapid response
Metabotropic - indirect, slow response via a signalling molecule
Out of GABAa and GABAb, which is ionotropic
GabaA
What are allodynia and hyperalgesia
Allodynia - Pain from a stimulus which is not normally painful
Hyperalgesia - Pain beyond expected from a normally painful stimulus
What is the Meningismus triad of symptoms
A headache, Neck stiffness, photophobia
What is the empirical treatment for Bacterial Meningitis
IV Ceftriaxone 2g Bd (+ IV ampicillin if suspected Listeria)
Chloramphenicol + Vancomycin if allergy
Which gene is implicated in Parkinson’s
LRRK2 gene
Parkinson’s triad
Pill rolling resting tremor
Brady/Akinesia
RIgidity (cog-wheel or lead pipe)
What can Levodopa be given with for treatment of Parkinsons’s
Carbidopa
Prevents the breakdown of levodopa in the bloodstream so more levodopa can enter the brain
Which cells undergo reactive gliosis and what does this involve
Astrocytes
Hypertrophy + Hyperplasia
1-2 weeks post-trauma
Which reaction do neurons undergo in response to hypoxia/ischemia and how long does this take
Red Neuron reaction
12-24 hours
What are Lewy Bodies made of
Alpha-synuclein
What are the two histopathological hallmarks of Alzheimer’s
Neurofibrillary tangles
Plaques
What are the tangles and plaques made up of in Alzheimer’s disease
Neurofibrillary *Tangles –> hyperphosphorylated *Tau protein
Plaques –> Beta-amyloid protein
Name 2 drugs that can be given for Alzheimer’s and how they work
Rivastigmine –> Cholinesterase inhibitor
Memantine –> Voltage-dependant NMDA receptor antagonist
What are Pick’s Cells and Pick’s bodies and which disease are they seen in
Pick’s cells –> Swollen Neurons
Pick’s bodies –> Filamentous inclusions
Both seen in Frontotemporal dementia
What is the normal range of intracranial pressure
9-11 mmHg
What occurs during a sub-falcine herniation
Cingulate gyrus herniates under the flax cerebri
What occurs during a Transtentorial herniation
Medial temporal lobe herniates under tentorium cerbelli
What occurs during a tonsillar herniation
Cerebellar tonsils herniate through the foramen magnum
What is Cushing’s triad and what does it suggest
Increase in Systolic Bp, Decrease in heart rate and Abnormal breathing
suggests tonsillar herniation
Which disease will cause oligoclonal bands on electrophoresis of CSF
Multiple Sclerosis
What are the Uhthoff phenomenon and L’hermitte sign and which disease can they be seen in
Uhthoff phenomenon –> Worsening of vision symptoms following a rise in body temperature
L’hermitte sign –> Upper limb paraesthesia on neck flexion
How does curare affect the neuromuscular junction
Blocks Ach receptor at NMJ
Curare is only harmful if administered via which routes
IM or IV
How does botox affect the neuromuscular junction
Cleaves proteins involved in Ach vesicle formation
Antibodies to which structures are created in Lambert Eaton syndrome
Pre-synaptic Ca channels
Antibodies to which structures are created in Myasthenia gravis
Post-synaptic Ach Receptor
What is the commonest muscular dystrophy
Myotonic Dystrophy
The levels of which neuropeptide will be low in CSF in Narcolepsy
Hypocretin
Which tracts carry ‘fast’ and ‘slow’ pain respectively
Fast pain –> Spinothalamic tract
Slow pain –> Spinoreticular tract
Which sensory neuron types carry ‘fast’ and ‘slow’ pain respectively (think about the degree of myelination)
Aδ –> fast pain
C –> slow pain
Which 3 brainstem regions are important in pain modulation
Peri-aqueductal gray
Locus coeruleus
Nucleus raphe magnus
Which brainstem region provides profound analgesia when excited
Peri-Aqueductal Gray (PAG)
Which brainstem region produces endogenous opioids and what are they called
Enkephalins –> produced by Nucleus Raphe Magnus
What are the 3 kinds of opioid receptors and which ones do opioid analgesics mostly work on
Mu –> most analgesic action of opioids work on these
Delta
Kappa
Name the basal ganglia
Putamen Globius palladius Subthalmic nucleus Caudate nucleus Substantia nigra
A hot-cross bun sign on MRI suggests which disease
Multi-system atrophy
What are the classical symptoms of multi-system atrophy
Parkinsonism
Autonomic dysfunction
Cerebellar dysfunction
How is Cerebral Perfusion Pressure calculated
Mean Arterial Pressure - Intra Cranial pressure
What is Split Hand syndrome and which disease can it be seen in
Preferential wasting of thenar muscles
seen in ALS
What type of dementia is ALS associated with
Frontotemporal dementia
How could you differentiate between ALS and PLS
ALS has upper motor neurone signs in the legs and lower motor neurone signs in the arms
PLS has no lower motor neurone features
What is the only drug available for Motor Neurone Disease
Riluzole
Which type of dementia is suggested if a patient presents before the age of 65
Frontotemporal dementia
What is Hoffman’s sign
holding the middle finger at the joint closest to the fingernail
“flicking” the nail of the person’s middle finger, using their other hand.
If there is no movement in the index finger or thumb after this motion, the person has a negative Hoffman’s sign. If the index finger and thumb move, the person has a positive Hoffman’s sign
If a patient presents within 7days of a suspected TIA, what should you do
300mg Aspirin and specialist review in 24hours
Anti-psychotics should be avoided in patients with which disease
Parkinson’s
If someone is seizuring in the community for longer than 5 minutes, what should be administered
Rectal Diazepam 10mg
Which cause of status epilepticus should be ruled out first
Hypoxia
Which epilepsy drug causes inhibition of the P450 system
Sodium Valproate
Aphasia as a symptom suggests a stroke in which artery
Dominant hemisphere middle cerebral artery
Usually left
Name 5 sinister signs of a headache
Vomiting >1 Neuro deficit Decreased GCS A progressive headache plus fever Positional/ Valsalva headache
What is the gold standard test for diagnosing Degenerative Cervical Myelopathy
MRI
What does a triad of Ataxia Dementia Urinary incontinence suggest?
Normal pressure hydrocephalus
What is the recommended treatment for Bell’s Palsy and is it an upper or lower motor neurone disease
Prednisolone and lubricating eye drops
Lower Motor Neurone
What is Todd’s Paresis and which disease is it seen in
Post-Ictal weakness seen in focal seizures
What is Hereditary Sensori-Motor Neuropathy also known as and how many types are there
Charcot-Marie-Tooth Disease 2 type (type 1 - Autosomal Dominant)
What does sinusitis + fever + focal neurology suggest
Cerebral Abscess
What is Saturday Night Palsy
Compression of radial nerve against humeral shaft causing wrist drop
Which neurological condition are tetracycline antibiotics associated with
Idiopathic Intracranial Hypertension
What are 3 treatments for Idiopathic Intracranial Hypertension
Weight loss
Acetazolamide
Topiramate
Name the 4 ipsilateral and 1 contralateral symptom involved in lateral medullary syndrome
Ataxia
Nystagmus
Dysphagia
Cranial nerve palsy
Contralateral hemisensory loss
Autonomic dysreflexia can only occur above which vertebral level
T6
What sort of symptoms occur in autonomic dysreflexia
Extreme hypertension, sweating & flushing above the level of the cord lesion
What are Shagreen patches and which disease are they seen in
Rough patches of skin over the lumbar spine
seen in Tuberous Sclerosis
What is hyposmia and which neurology condition could it be an early sign of
it is a reduced ability to smell and to detect odors
Can be a sign of Parkinson’s
What should you give for suspected Listeria Meningitis if the patient is allergic to penicillin
Co-trimoxazole alone
Which symptom of Normal Pressure Hydrocephalus precedes all the others
Ataxia
In Normal Pressure Hydrocephalus Ataxia, do people tend to fall backwards or forwards
backwards
Hyperhidrosis is an early feature of which neuro condition and why does it happen
A feature of early-stage syringomyelia
Indicates hyperactivity in pre-ganglionic neurons
What is the treatment for cerebral venous thrombosis
Heparin/Warfarin for 6 months
lifelong if already prothrombotic
