Neuroscience Flashcards
Briefly explain the neuromuscular junction
- Action potential arrives at the axon terminal
- Calcium influx
- Vesicles of Ach exocytose
- ACh is released into the junction
- ACh diffuses across , and binds, causing sodium to influx to the muscle cell
- Ach is broken down by acetylcholinesterase
What ion is responsible for muscle contraction?
Ca2+
What are olgiodendrocytes?
The myelinating cells of the CNS. They are surrounded by myelin sheath.
What are Schwann cells?
the myelinating cells of the PNS. They envelop PNS cell axons
What are Anti-AChR antibodies associated with?
Myasthenia Gravis
What are Anti-MuSK antibodies associated with?
Myasthenia Gravis
What are Microglia?
The resident immune cells of the CNS, and they proliferate at sites of injury
What are Astrocytes?
“Star-like” cells which are the most numerous glial cells in the CNS. They provide many functions including enveloping synapses, homeostatic function, metabolic support etc.
Which cells are the “resident immune cells of the CNS”? A) Olgiodendrocytes B) Schwann cells C) Microglia D) Astrocytes E) Glia
C
Which of the following is NOT a part of the blood brain barrier?
A) Astrocyte end feet
B) Fenestrated capillaries
C) Endothelial tight junctions
D) Pericytes
E) Specific transporters for glucose, water, essential ions etc.
B
What is temporal summation?
A) Lots of axons firing simultaneously
B) A new action potential cannot occur
C) When the membrane becomes more negatively polarised than its resting potential
D) A new action potential can only occur if the depolarisation is more significant than the previous one
E) One axon firing multiple times
E
Which of the following is a fast neurotransmitter? A) GABA B) Dopamine C) Noradrenaline D) Serotonin
A
A patient prevents with double vision. She has noticed that when she brushes her hair, her arms seem to get very tired and she has to rest before she’s managed to brush her whole head. You notice that she has ptosis and seems short of breath. Her speech seems to be getting gradually more slurred as she speaks. What is it likely to be?
Myasthenia Gravis
What tests can you do to check for MG?
- Ice pack test: Ptosis improves with ice
- Cogan’s lid twitch: Patient follows your finger up then down, then middle and the patients lid will twitch up
Which component of the eye controls the shape of the lens? A) Sclera B) Cornea C) Choroid D) Ciliary body E) Retina
D
What is a defective outer/middle ear known as? A) Sensorineural hearing loss B) Tympanic hearing loss C) Vestibular hearing loss D) Transmissural hearing loss E) Conductive hearing loss
E
What are the three components of the cochlea?
scala tympani, scala media, scala vestibuli
What is the cerebrum embryonically derived from?
cerebrum derived from the telencephalon of prosencephalon
What are the thalamus, hypothalamus and epithalamus embryonically derived from?
the diencephalon of prosencephalon
What is myasthenia gravis?
An autoimmune disease against nicotinic acetyl choline receptors in the neuromuscular junction
What is the midbrain embryonically derived from?
Mesencephalon
What are the pons and cerebellum embryonically derived from?
metencephalon of rhombencephalon
What is the medulla embryonically derived from?
Myelencephalon of the rhombencephalon
Which of the following is not an element of the human stress response? A) Environmental B) Biochemical C) Emotional D) Cognitive E) Physiological
A
Which extrapyramidal tract is responsible for head/eye movements in response to visual stimuli? A) Corticobulbar B) Tectospinal C) Rubrospinal D) Vestibulospinal E) Reticulospinal
B
Which extrapyramidal tract is responsible for the musculature of the head and neck? A) Corticobulbar B) Tectospinal C) Rubrospinal D) Vestibulospinal E) Reticulospinal
A
What malignancy is associated with myasthenia gravis?
Thymoma
What is a myasthenic crisis?
A medical emergency of respiratory failure, impaired swallow and/or severe limb weakness due to myasthenia gravis
How would you treat a myasthenic crisis?
Plasmapheresis and IV immunoglobulins
Which extrapyramidal tract originates in the red nucleus? A) Corticobulbar B) Tectospinal C) Rubrospinal D) Vestibulospinal E) Reticulospinal
C
Which extrapyramidal tract originates in the superior colliculus? A) Corticobulbar B) Tectospinal C) Rubrospinal D) Vestibulospinal E) Reticulospinal
B
Which extrapyramidal tract is responsible for posture and balance? A) Corticobulbar B) Tectospinal C) Rubrospinal D) Vestibulospinal E) Reticulospinal
D
Which of the following is a characteristic feature of a LMN lesion? A) Hyperreflexia B) Absent fasciculation C) Atrophy D) Hypertonia E) Paralysis of group of muscles
C
What are the classic features of an UMN lesion?
No wasting, hypertonia, paralysis of a group of muscles, hyperreflexia, absent fasiculation, present Babinski sign and clasp-knife reflex
What component of the brain produces dopamine? A) Amygdala B) Globus pallidus C) Subthalamic nucleus D) Hypothalamus E) Substantia Nigra
E
A patient’s blood tests show positive anti-AcR antibodies, and is positive in the ice pack test. How would you treat this patient?
Ach-esterase inhibitors= Pyridostigmine
Steroids= Prednisolone
Steroid sparing agents= Azathioprine
Through which foramen does V1 exit the skull? A) Foramen Ovale B) Superior orbital fissure C) Foramen spinosum D) Foramen magnum E) Foremen rotundum
B
What sensation does the anterior spinothalamic tract carry? A) Pain and temperature B) Deep/ chronic pain C) Fine touch D) Vibration E) Crude touch and pressure
E
What sensation does the DCML pathway carry? A) Pain and temperature B) Deep/ chronic pain C) Fine touch and vibration E) Crude touch and pressure
C
What sensation does the lateral spinothalamic tract carry? A) Pain and temperature B) Deep/ chronic pain C) Fine touch and vibration E) Crude touch and pressure
A
What sensation does the spinoreticular tract carry? A) Pain and temperature B) Deep/ chronic pain C) Fine touch and vibration E) Crude touch and pressure
B
A 35 year old woman comes to her GP complaining of pain that comes and goes, but worsens in the shower. What is it likely to be? A) Myasthenia gravis B) Motor neuron disease C) Multiple sclerosis D) Parkinson’s disease E) ALS
C
What is a transient loss of consciousness?
Spontaneous loss of consciousness with complete recovery
What are the types of syncope?
Vasovagal
Situational
Orthostatic hypotension
Cardiac
What are the different types of TLOC?
Syncope
Seizure
Non-epileptic attack disorder
What is meant by “prodrome”?
Any symptoms that happened before a TLOC (e.g. aura, nausea)
What is a cardiac syncope?
Temporary but sudden reduction in blood supply and hence oxygen to the brain as a result of cardiovascular conditions
A patient has a seizure that lasts for 60 seconds. He first goes stiff and then has myoclonic jerking. Afterwards, he is confused for a few hours. What is it likely to be?
Generalised tonic-clonic epilepsy
What is the different between a generalised and focal seizure?
Focal generates in a circuit localised to one hemisphere (But may spread) whereas generalised is not localised
A patient presents after she has had a loss of consicousness. Her husband says that she was moving randomly, with her head side to side, and it lasted “about 4 minutes”. Afterwards she was very upset. This was her third attack in two weeks. What is it likely to be?
Non-epileptic attack disorder (long seizure, head moving side to side, crying afterwards, frequent attacks)
What is the sagittal plane?
Slicing the body through the midline leaving a left and right side
What is the coronal plane?
Slicing the body to leave a front and a rear section
What is the transverse plane?
Slicing the body to leave an upper and a lower section
How many pairs of spinal nerves are there?
32
What do autonomic motor fibres supply?
Smooth muscle and glands (upper abdomen)
What is a block of muscle supplied by a single nerve referred to as?
Myotome
What is a block of skin sensation supplied by a single nerve referred to as?
Dermatome
Which cranial nerves have parasympathetic control?
10, 9, 7, 3
What dermatome supplies the heart?
T1
Why does heart pain radiate down the arm?
The heart and the arm are supplied by T1 dermatome, so pain is felt all along here
Where do the sympathetic nerves come out of the spinal cord?
T1-L2
What is the nervous supply of the foregut?
Greater splanchnic nerve (T5-T9)
What is the nervous supply of the midgut?
Lesser splanchnic nerve (T10-T11)
What is the nervous supply of the hindgut?
Least splanchnic nerve (T12)
What are the typical presentation of brown-Sequard syndrome?
- Total loss of sensation at the lesion
- Loss of normal sensation, and paralysis from the injury downwards, on the same side
- Loss of pain and temperature on the opposite side from two levels below the lesion
What are the layers of the meninges?
PAD out
- Pia Mata
- Arachnoid mata
- Dura Mata
Where does the spinal cord finish?
L1
What is the difference between a lumbar puncture and an epidural?
A lumbar puncture goes through the meninges, so uses a different needle, whereas epidurals don’t go through the dura.
What is cranial nerve I, what are its components, and what is its functions?
Olfactory
Sensory
= Smell
What is cranial nerve II, what are its components, and what is its functions?
Optic
Sensory
= Site
What is cranial nerve III, what are its components, and what is its functions?
Occulomotor
Motor and parasympathetic
= Movement of eye muscles and pupillary constriction
What is cranial nerve IV, what are its components, and what is its functions?
Trochlear
Motor
= Movement of the eye muscles
What is cranial nerve VI, what are its components, and what is its functions?
Abducens
Motor
= Movement of the eye muscles
What is cranial nerve V, what are its components, and what is its functions?
Trigeminal
Sensory and motor
= Sensation of some of the face, muscles connected to the mandible
What is cranial nerve VII, what are its components, and what is its functions?
Facial
Sensory and Motor
= Motor to the face (bilateral to forehead) and taste (ant 2/3)
What is cranial nerve VIII, what are its components, and what is its functions?
Vestibulocochlear
Sensory
= Hearing and balence
What is cranial nerve IX, what are its components, and what is its functions?
Glosopharyngeal
Sensory and motor
= Sensation to post throat, taste of post 1/3 tongue, motor
What is cranial nerve X, what are its components, and what is its functions?
Vagus
Sensory and motor
= Muscles of the neck, gag reflex,
What is cranial nerve XI, what are its components, and what is its functions?
Accessory
Motor
= Shrugging sholders, turning head
What is cranial nerve XII, what are its components, and what is its functions?
Hypoglossal
Motor
= Movement of tongue
Are ischaemic or haemorrhagic strokes more common?
Ischaemic (80%)
How does AF lead to embolus?
AF causes blood to stagnate in the auricular appendage and this stasis results in a clot. If the heart then returns to sinus rhythm, this clot will be pushed out of the heart.
Where does the middle cerebral artery supply?
The lateral surfaces of the brain
Where does the posterior cerebral artery supply?
The posterior part of the brain
Where does the anterior cerebral artery supply?
The middle of the brain (approx 2 cm either side of the longitudional fissure)
What is Brocas area?
The motor speech area= tells the motor area what to say
What is Wernike’s area?
The posterior speech area= Understands language
Where is the primary motor area?
The pre-central gyrus
Where is the primary sensory area?
The post-central gyrus
Which areas of the body are in the anterior cerebral artery supply territory on the motor and sensory gyrus?
The lower limbs
Which areas of the body are in the middle cerebral artery supply territory on the motor and sensory gyrus?
The upper limbs
What are the symptoms of extradural haemorrhage?
- Lucid period
- Rapid rise in inter-cranial pressure
- Coning and death if not treated
What is the commonest cause of subdural haemorrhage?
Bleeding of the bridging veins
What is the commonest cause of subarachnoid haemorrhage?
Rupture of the arteries forming the circle of Willis- often because of Berry Aneurysms
What is the commonest cause of the extradural haemorrhage?
Trauma
List some common stroke differentials
- Hypoglycaemia
- Brain tumour
- Drug/ Alcohol toxicity
- Seizure
- Migraine with aura
- Wernicke’s encephalopathy
What is the ACBD2 score used for?
Risk of having a stroke after a TIA in the next seven days
What is the typical triad of symptoms in meningitis?
Headache
Fever
Neck stiffness
What would be the typical treatment of meningitis?
IV Cefotaxime or IV ceftriaxone
Add amoxicillin if immunocompromised
Steroids
How is meningitis diagnosed?
- Blood cultures
- If immunocompromised, older, or low GCS = CT before Lumbar puncture
- Lumbar puncture (cells, proteins and glucose)
What would high polymorphs, raised protein and low glucose in CSF indicate?
Bacterial infection e.g. bacterial meningitis (N. Meningitis, Strep pneumoniae, Listeria spp., etc)
What would high lymphocytes, normal./ slightly raised protein and low glucose in CSF indicate?
Viral infection e.g. viral meningitis (Enterovirus, herpes simplex, varicella zoster virus)
What are the most common meningitis causing pathogens in neonates?
E. Coli, group B strep and listeria
What are the most common meningitis causing pathogens in children?
Neisseria meningitis, Strep pneumoniae, haemophilius influenzae
What are the most common meningitis causing pathogens in adults?
Neisseria meningitis, Strep pneumoniae
What are the usual causes of encephalitis?
Herpes simplex
Varicella zoster
What would a temporal lobe inflammation on MRI be indicative of?
Encephalitis due to herpes simplex virus
What is the most common primary brain tumour?
Astrocytoma
What neoplasms are most likely to metastasise to the CNS?
- Non-small cell lung
- Small cell lung
- Breast
- Melanoma
- Renal cell
- GI
How are brain tumours classified?
WHO classification
What are the classic symptoms of brain tumours?
- Headaches associated with nausea and vomitting
- Progressive focal neurological deficit depending on where the tumour is
- Seizures
- Papilloedema
- Generalised B symptoms
What chemotherapy is used for glioma?
Temozolomide
Does MS mainly affect the grey or the white matter?
White matter
Is MS worse in the cold or heat?
Heat
What is uhthoff phenomenon?
An increase in pain and weakness with an increase in temperature in MS
What are the 4 types of MS?
- Relapsing/ Remitting MS
- Primary progressive MS
- Secondary progressive MS
- Progressive/ relapsing MS
What is Kernig’s sign?
An inability to allow full extension of the knee when the hip is flexed at 90 degrees- indicates subarachnoid haemorrhage or meningitis
How long do epileptic seizures typically last?
30-120 Seconds
What is the first line treatment for focal epilepsy?
Carbamazepine or lamotrigine
What is the first line treatment for generalised epilepsy?
Valproate or lamotrigine
What is Brodmann’s area 44?
Brocas area
What is Brodmann’s area 22?
Wernicke’s area
What are the 2 ways that an anaplastic astrocytoma can develop into a glioblastoma?
- Mutation of IDH1 results in build up of 2-hydroxyglutarate
- Catastrophic mutation resulting in a primary glioblastoma (no anaplastic astrocytoma)
What is the most common brain tumour in children?
Pilocytic astrocytoma- good prognosis
What tumour type has rosenthal fibres?
Pilocytic astrocytoma
What is papilloedema?
Swelling of the optic disc due to obstructed venous return due to a raised ICP
What are the clinical features of a raised ICP?
- Headaches (Worse on coughing/ leaning forward)
- Drowsiness
- Vomitting
What things could cause raised ICP?
- Tumour
- Haemorrhage
- Trauma
- Abscess
What is the large hole at the base of the skull called?
Foramen Magnum
What is cerebellar tonsillar herniation?
When the cerebellar tonsils move downward through the foramen magnum possibly causing compression of the lower brainstem and upper cervical spinal cord
What is lateral tentorial herniation?
Unilateral or asymmetric mass effect. The medial parts of the temporal lobe are pushed into the ambient cistern and up against the brainstem
List some common primary headaches
Migraine
Cluster
Tension
List some types of secondary headaches
Meningitis SAH GCA Idiopathic intracranial hypertension Medication overuse headache
What is the criteria for diagnosing migraine?
5 attacks lasting 4-72 hrs each
With two of the following= Unilateral, pulsing, moderate/severe and aggravation by routine physical activity
And one of= Nausea and/or vomitting, photophobia and phonophobia
What is the commonest primary headache?
Tension headache
A patient presents with a severe headache around one temple. She says they normally last about half an hour and happens every other day roughly. Her eye tends to get watery whilst its happening. What is it likely to be? A) Cluster headache B) Tension headache C) Migraine D) Trigeminal neuralgia E) Drug overuse headache
A
A patient presents with headache that is a moderate intensity. She doesn't get any nausea or vomitting, and it doesn't get aggrevated by physical acyivity. She says she can still go to work with these headaches, but she is worried it could be something more sinister as she has attacks that last up to 2 days at a time. What is it most likely to be? A) Cluster headache B) Tension headache C) Migraine D) Trigeminal neuralgia E) Drug overuse headache
B
A patient presents with a severe headache that seems to get worse when she exercises. These last around 8 hours at a time, and mainly affects the right side. She says she often feels ill due to the pain and feels better if she sits in a dark cold room. What is it likely to be? A) Cluster headache B) Tension headache C) Migraine D) Trigeminal neuralgia E) Drug overuse headache
C
A patient presents with a extreme pain in her left cheek. She says these attacks only last about 10 seconds at a time but happen quite often. She reports them feeling like an electric shock. What is it likely to be? A) Cluster headache B) Tension headache C) Migraine D) Trigeminal neuralgia E) Drug overuse headache
D
A 24 year old man presents with a gradual onset headache and mild photophobia. On examination he is drowsy and has a fever with neck stiffness. What is it likely to be? A) Giant cell arteritis B) Encephalitis C) Meningitis D) Subarachnoid haemorrhage E) Tension headache
C
A 30 year old man presents with a sudden onset of generalised headache that started yesterday whilst he was at the gym doing weights. He also reports nausea and vomitting. His examination is all normal. What is it likely to be? A) Giant cell arteritis B) Encephalitis C) Meningitis D) Subarachnoid haemorrhage E) Tension headache
D
A 30 year old woman presents with 2 months of headache that is generalised and worse on lying down. She also has visual obscurations. On examination she has a high BMI and papilloedema. What is it likely to be? A) Giant cell arteritis B) Idiopathic intracranial hypertension C) Meningitis D) Subarachnoid haemorrhage E) Tension headache
B
A 59 year old woman presents with a severe headache. On blood tests she has has ESR raised and she is feverish. She also reports getting cramping of the jaw when she eats. What is it likely to be? A) Giant cell arteritis B) Idiopathic intracranial hypertension C) Meningitis D) Subarachnoid haemorrhage E) Tension headache
A
What is apraxia?
Disorder of consciously organised patterns of movement or impaired ability to recall acquired motor skills
What happens in a LMN lesion?
- Muscle tone normal or reduced
- Muscle wasting
- Fasciculation
- Reflexes depressed or absent
What is fasciculation?
Twitching
How is Alzheimer’s typically diagnosed?
Clinical history of over 6 months including cognitive impairment, and memory impairment. This can be tested with the MMSE. You can also detect amyloid using PET.
What are the clinical features of lewy Body dementia?
- Fluctuating cognition
- Variation in alertness and awareness
- Visual hallucinations
- Parkinsonism
- Memory loss is a later feature
List some ways to prevent dementia
- Healthy bod weight
- Not smoking
- Low alcohol
- Healthy diet
- Regular exercise
What is the main medication for alzheimers?
ACh-ase inhibitors e.g. donezepil
What happens in a 3rd nerve palsy?
Fixed dilated pupil
What nerves go through the cavernous sinus?
Occulomotor nerve Trochlear nerve Ophthalmic division of the trigeminal Maxillary division of the trigeminal Abducens nerve
What is the most common lesion of the facial nerve?
Bells palsy
What are the symptoms of an ACA stroke?
- Leg weakness
- Gait apraxia
- Sensory disturbance in the legs
- Incontinence
- Drowsiness
- Akinetic mutism
What are the symptoms of a MCA stroke?
- Contralateral arm and leg weakness
- Contralateral sensory loss
- Hemianopia
- Aphasia
- Dysphasia
- Facial droop
What are the symptoms of a PCA stroke?
- Contralateral homonymous hemianopia
- Cortical blindness
- Visual agnosia
- Prosopagnosia
- Dyslexia
- Unilateral headache
What are the symptoms of a posterior circulation stroke?
- Motor deficits such as hemiparesis or tetraparesis
- Dysarthria and speech impairment
- Vertigo and vomitting
- Visual disturbances
- Altered consciousness
What is given in the first 4.5 hrs of an ischaemic stroke?
Thrombolysis
A patient presents with right sided weakness, dysarthria, loss of vision and difficulty speaking. What do they likely have? A) ACA stroke B) MCA stroke C) PCA stroke D) Posterior circulation stroke E) None of the above
B
What is meant by a coup lesion?
A lesion that occurs at the site of injury. Contrecoup is a lesion that occurs away from the site of injury
A patient presents with stiffness in his left leg. His wife says that he walks more slowly, and seems to drag his left leg. There is subseqeuent gradual tremor in the left hand, with problems doing up buttons and writing smaller. What is it likely to be? A) Motor neuron disease B) Myasthenia gravis C) Parkinson's disease D) Huntington's disease E) Guillain-Barre Syndrome
C
What are the 3 cardinal features of Parkinsons disease?
- Brady/Akinesia= Problems doing up buttons, writing smaller
- Tremor at rest
- Rigidity and pain
What is the gold standard treatment for Parkinson’s disease?
Levodopa and a decarboxylase inhibitor e.g. co-Careldopa
You are sent a patients results from an MRI. They report atrophy of the substantia nigra. What condition does the patient likely have?
Parkinson’s Disease
Give an example of a dopamine agonist
Ropinirole
What would you prescribe for a young Parkinson’s disease patient?
Dopamine agonist such as ropinirole
What is the main cause of peripheral neuropathies?
Diabetes
What are the 3 criteria for a total anterior circulation stroke?
Unilateral weakness (and/or sensory deficit) of face, arm and leg Homonymous hemianopia Higher cerebral dysfunction (dysphasia, visuospatial disorder)
What are the criteria for a partial anterior circulation stroke?
2 of…
Unilateral weakness (and/or sensory deficit) of face, arm and leg
Homonymous hemianopia
Higher cerebral dysfunction (dysphasia, visuospatial disorder)
What are the criteria for a posterior circulation stroke?
1 of…
Cerebellar or brainstem syndromes
Loss of consciousness
Isolated homonymous hemianopia
