Neurology Flashcards
What are the two main neurotransmitter in autonomic nerve system and what are the fibers they are secreted from?
Acetylcholine - cholinergic nerve fiber
Norepinephrine - adrenergic nerve fiber
Component of complete neurological exam
- mentation
- gait
- cranial nerve
- segmental reflexes
- proprioception
- palpation
- nociception
Paresis vs plegia
Paresis = weakness
Plegia = paralysis
True or False:
In the autonomic nerve system, all the pre-ganglionic neurons are cholinergic, no matter they belong to sympathetic or parasympathetic.
True
What are the differences between muscarinic and nicotinic receptors?
Muscarinic:
- G protein receptors
- Locates at all the effector cells at the end of all the parasympathetic nerve ending and some sympathetic nerve ending (e.g. sweat gland)
Nicotinic:
- Ligand-gated ion channels
- Locates at the autonomic nerve system synapses between preganglion and postganglion, somatic nerve ending (skeletal muscles)
Is SNS or PNS also called craniosacral division of ANS?
PNS
- SNS is also called thoracolumbar division of the autonomic nerve system
Parasympathetic nerve fibers leave the CNS through which cranial nerves and which nerve in the sacral region?
3, 7, 9, 10 (75%)
Pelvic nerves
What is the resting membrane potential for neuron?
-70 mV
Which part of the brain do thalamus and hypothalamus belong to?
Forebrain
Where is medulla oblongata?
Brainstem (connecting the brainstem to the spinal cord)
Where are the grey matter and white matter in the brain and spinal cord?
Brain: grey matter outside, white matter inside
Spinal cord: grey matter inside, white matter outside
Which spinal nerve root carries afferent neurons and which one carries efferent neurons?
Dorsal: afferent neurons
Ventral: efferent neurons
On MRI T1-weighing, what tissue is hyperintense and what tissue is hypointense? What about T2-weighing and fluid attenuated inversion recovery (FLAIR)?
T1:
- Fat hyperintense
- Fluid (e.g. CSF) hypointense
T2:
- Fluid and tissue with high fluid content hyperintense
- Fat variable
* also called “pathology scan” → inflammation, bleeding, edema will be whither
FLAIR
- Pure fluid (e.g. CSF, cystic fluid) become hypointense → facilitate differentiating
What is the difference between acute brain hemorrhage and chronic brain hemorrhage on the MRI T1 and T2 window?
T1
- Acute (< 24 hours): isointense or hypointense
- Chronic: hypointense
T2
- Acute: hyperintense
- Chronic: hypointense
Describe decerebrate rigidity and the lesion localization.
Stupuros/comatosen + opisthotonus and extension of all limbs
Lesion: rostral pons and midbrain
Describe decerebellate rigidity and the lesion localization.
Normal mentation + opisthotonus with extensor rigidity of the thoracic limbs and either extension or flexion of the pelvic limbs is present
Lesion: cerebellum
Describe Cheyne-Stokes breathing.
Periods of hyperpnea alternating with periods of apnea; can be seen with diffuse cerebral or thalamic disease and metabolic encephalopathies
Describe central neurogenic hyperventilation and the lesion.
Persistent hyperventilation that may result in respiratory alkalosis
Midbrain lesions
When a patient has decrease or absent PLR, where is the lesions?
Midbrain, CN II & III (PNS)
When a patient loses its oculocephalic reflex, where is the lesion?
CN 3, 6, 8
How will the left eye CN II injury affect the PLR?
When light shines to the left eye, there will be no PLR in both eye; when the light shines to the right eye, there will be direct and consensual PLR in both eyes
How will the left eye CN III injury affect the PLR?
When the light shines to the left eye, there will be consensual PLR to the right eye but no PLR in the left; when the light shines to the right eye, there will be direct PLR at the right eye but no consensual PLR to the left eye.
When the patient is miotic and there is no ocular injury, where is the lesion?
diencephalon (e.g. thalamus, hypothalamus)
- Hypothalamus is the origin of SNS pathway
What are the three categories of seizures?
1) Reactive
2) Structural
3) Idiopathic