Cranial Nerves Flashcards
Cranial nerves I-XII
I. Olfactory
II. Optic
III. Oculomotor
IV. Trochlear
V. Trigeminal
VI. Abducens
VII. Facial
VIII. Vestibulocochlear
IX. Glossopharyngeal
X. Vagus
XI. Accessory
XII. Hypoglossal
Sensory cranial nerves (afferent)
- olfactory
- optic
- vestibulocochlear
Motor cranial nerves (efferent)
- oculomotor
- trochlear
- abducens
- accessory
- hypoglossal
Mixed cranial nerves
- trigeminal
- facial
- glossopharyngeal
- vagus
Olfactory nerve function
- Sensory
- sense of smell
Optic nerve function
- sensory
- vision
Extrinsic eye muscles control
- oculomotor
- trochlear
- abducens
Oculomotor functions
- motor
- raising eyelid
- directing eyeball
- constricting the iris
- control lens shape
Trochlear nerve function
- motor
- projects to superior oblique muscle intorts (twist)
- depresses and abducts globe
Trigeminal nerve function
- motor
- projects to muscles of mastication and sensory to face, scalp, oral cavity
Trigeminal neuralgia
- long term pain disorder
- severe sudden shock of pain
Abducens nerve function
- motor
- projects to lateral rectus muscle (abducts eye)
Facial nerve functions
- mixed
- motor to muscles of facial expression
- parasympathetic stimulation of lacrimal, submandibular, and sublingual glands
- sensation to anterior 2/3 of tongue, ear canal, and tympanic membrane
Bells palsy
- temporary facial paralysis
- facial nerve damage
Vestibulocochlear nerve function
- sensory
- hearing (cochlear) and balance (vestibular)
Glossopharyngeal functions
- motor: innervates part of tongue and pharynx, provides motor fibers to parotid salivary gland (parasympathetic)
- sensory: fibers conduct taste and general sensory impulses from the tongue and pharynx
Vagus nerve functions
- motor: parasympathetic fibers to heart, lungs, and visceral organs
- sensory: taste
- visceral sensation from organs
Accessory nerve function
Innervates trapezius and sternocleidomastoid which moves head and neck
Hypoglossal nerve function
Innervates both extrinsic and intrinsic muscles of the tongue which contribute to swallowing and speech
Pheromones
Secreted chemical factor that triggers a social response in members of the same species
Pheromone types
- alarm
- food trail
- sex
Terminal nerve (CN 0)
- vestigial or may be related to the sensation of pheromones
- projects to areas involved in regulating sexual behavior
