Cranial Nerves Flashcards
What are the cranial nerves?
- olfactory (smell)
- optic (vision)
- oculomotor (eye movement [most extraocular movements], elevation of upper eyelid, pupillary constriction)
- trochlear (eye movement [down and in])
- trigeminal (Motor: mm of mastication; Sensory: face, tongue [not taste])
- abducens (eye movement [lateral deviation])
- facial (sensory: taste [ant 2/3 tongue]; motor: facial mm)
- accoustic (balance/equilibrium: vestibular division; hearing: cochlear division)
- glossopharyngeal (motor: pharynx; sensory: pharynx and posterior tongue, including taste)
- vagus (motor: palate, pharynx and larynx; sensory: pharynx and larynx, PaNS)
- accessory (controls trapezius and SCM)
- hypoglossal (tongue)
Which cranial nerves originate in the brainstem?
CN 3-12
Cranial nerves are numbered according to what sequence?
order in which they leave the brain (from sup. to inf.)
The olfactory nerve is a collection of sensory nerve rootlets that pass through the many openings of the:
cribiform plate of the ethmoid
Hair cells in the nose have ___ on one side and an ___ on the other side in order to transduce chemical activity into APs.
cilia; axon
About how many olfactory receptors are in humans? In german sheppards?
40 million; 2 billion
People with no sense of smell have a disorder called:
anosmia
An olfactory hallucination is called:
phantosmia
A condition in which a smell that’s present in the environment is distorted:
parosmia
What’s the aka for the blind spot in the eye?
scotoma
The clinical term for near-sightedness.
myopia (means you can see better close up than far away
The clinical term for far-sightedness.
hyperopia (mean you can see better far away than close up)
Myopia and hyperopia are due to:
a misshapen cornea, the transparent part of the eye that covers the iris and pupil
With ___ a person has difficulty focusing on an object that is close up.
presbyopia
A ___ is a clouding of the lens most commonly due to aging.
cataract
The central portion of the retina is called the:
macula
___ is a term for a group of disorders that result in optic nerve damage, often associated with increased fluid intraocular pressure.
glaucoma