1- Clinical Neuroscience Flashcards
What are the major cell types in the nervous system? ๐๐ EXAM 2021
1- Neurons
These comprise a diverse collection of cells that marry afferent input to internal brain states to produce perception and behavior.
2- Astrocytes
Establish the bloodโbrain barrier, flux ions, repair and form scars in injury
3- Oligodendroglia and Schwann cells
Form myelin in brain/spinal cord and periphery
4- Microglia
Resident inflammatory phagocytes in infection, degeneration, demyelination
5- Ependymal cells
Neuroepithelial cells lining the ventricles, choroid, spinal cord central canal, form cerebrospinal fluid, nonrenewing stem cell pool producing neurons in adult central nervous system (CNS) injury
Neurology Secrets 6th Edition Chapter 1 pg1
What are the major subcellular compartments of the canonical neuron? ๐๐
- Soma: body of the neuron
- Dendrites: processes that emanate from the soma and subserve synaptic connections
- Axon: projection from the soma that terminates on postsynaptic partners
- Nodes of Ranvier: area between myelinated axonal segments densely populated by voltage-gated Na+ channels that regenerate action potentials
- Myelin: a sheath comprised primarily of lipids that electrically insulates the axon and allows for salutatory conduction at unsheathed nodes
Neurology Secrets 6th Edition Chapter 1 pg1
What ionic currents support action potential generation and propagation? ๐๐
1- Depolarizing phase Na+ currents
2- Repolarizing phase
Inactivation of Na+ currents (accounts for refractory period of action potentials)
Activation of K+ currents (accounts for membrane hyperpolarization)
Neurology Secrets 6th Edition Chapter 1 pg4
What are some examples of calcium channelopathies? ๐
1- LambertโEaton syndrome (LEMS)
Antibody-mediated autoimmune attack on P/Q type voltage-gated Ca channels in the presynaptic neuron at the neuromuscular junction
2- Hypokalemic periodic muscle paralysis
Mutation in gene coding for the skeletal voltage-gated Ca2+ channel
Neurology Secrets 6th Edition Chapter 1 pg5
What are some examples of sodium channelopathies? ๐
Hyperkalemic periodic paralysis
Generalized episodic flaccid weakness
Neurology Secrets 6th Edition Chapter 1 pg5
What is serotonin syndrome? 4 marks ๐๐
Serotonin syndrome
- Agitation
- Confusion
- Muscle rigidity
- Fever
Medications
- SSRI: Prozac, Cipralix
- Antipsychotics: Haloperidol, quetiapine
- Ondansetron
- Metoclopramide
Neurology Secrets 6th Edition Chapter 1 pg7
Cause of Horner Syndrome (Central, Pre & Post Ganglionic)๐๐ EXAM 2019-2020
Central 1st Order
- Stroke
- Tumor
- Syringomyelia
- Myelitis
Pre-Ganglionic 2nd Order
- Cervical rib
- Brachial Plexopathy
- Pancoast Tumor
- Iatrogenic (surgery, chest tube)
- Thyroid tumor
Post-Ganglionic 3rd Order
- Trauma
- Internal carotid artery aneurysm
- Cavernous sinus lesion
- Pituitary Tumor
Give two CNS tracts responsible for a positive Rombergโs sign
Name 3 different kinds of sensory input required to maintain balance ๐
- Dorsal column (proprioception)
- Vestibulospinal tract
- Visual pathway
Give the spinal tracts for ๐
a. Tactile and kinesthetic sense from hands
b. Tactile and kinesthetic sense from feet
c. Golgi and spindle afferents from feet/LE
- Fasciculus cuneatus (vertebral level T7 and above)
- Fasciculus gracilis (vertebral level T6 and below)
- Spinocerebellar
Name 3 tracts from the midbrain and pons
- Spinothalamic tract
- Corticospinal tract
- Dorsal column
Clinical criteria of dementia.
DSM-IV Criteria for Dementia
- Memory impairment
- One or more of the following
- Aphasia
- Apraxia
- Agnosia
- Impair executive functions (planning, organizing, sequencing, abstracting)
- Significant impairment in social or occupational functioning and represents a decline from prior functions
- Deficits do not occur exclusively as part of a delerium
https://www.uptodate.com/contents/image?imageKey=NEURO%2F91276
List 3 locations of lesions causing a left homonymous hemianopsia ๐๐
- Right optic tract (D)
- Right optic radiation in parietal lobe (G)
- Right occipital lobe (H)
https://geekymedics.com/visual-pathway-and-visual-field-defects/
Name the cranial nerve involved ๐
a. Left visual field
b. Left tongue deviation
c. Right mastication
d. Right head rotation
e. Inward and downward movement of L eye
- Left Optic nerve
- Left Hypoglossal
- Left Trigeminal
- Left Spinal Accessory N
- Left trochlear (SO)
List 4 Causes of Bulbar vs Pseudobulbar palsy ๐๐
Common Sing & Symptoms ๐
Pseudobulbar (UMN)
- Amyotrophic lateral sclerosis (ALS) (Corticospital)
- Multiple sclerosis (MS) (Corticospital or cortex)
- Bilateral Corticobulbar Stroke
- Traumatic brain injury
- Parkinsonโs disease
- Multiple system atrophy, Progressive supranuclear palsy
- Alzheimerโs disease
- High brain stem tumors
Bulbar (LMN)
- Brainstem Infarction: lateral or medial medullary infarction
- Synringobulbia
- Amyotrophic lateral sclerosis (ALS) (Anterior horn cell)
- Polio (Anterior horn cell)
- Botulism
- GuillainโBarrรฉ syndrome (Periphral n.)
- Myasthenia gravis (NMJ)
Common Sing & Symptoms
- Dysphagia (difficulty in swallowing)
- Difficulty in chewing.
- Nasal regurgitation.
- Drooling of saliva
- Difficulty breathing (airway obstruction).
- Dysphonia
- Dysarthria, slurred speech
Difference
- Flaccid (LMN) vs spastic (UMN) tongue and jaw
- Hypo (LMN) vs Hyperflexia (UMN) Jaw Jerk
- Emotional liabelity (pseudobulbar)
After a history of muscle disease is elicited, what findings can be expected on physical examination?
Routine Neuro Exam: Inspection - Sensroy - Tone - Motor - Reflexes
- Normal muscle bulk, atrophy or fasciculations
- Normal sensory examination
- Muscle tone is usually normal or mildly decreased.
- Proximal symmetric weakness.
- Reflexes are also normal or mildly decreased.
Neurology Secrets 6th Edition Chapter 3 pg43