cranial nerves Flashcards
Cranial nerves are pairs of nerves that connect the brain to different parts of your head, neck, and trunk.
Structure and function
structure
12 cranial nerves in each hemisphere
Originate within the brain
Part of the peripheral nervous system (PNS)
Function
The function of cranial nerves is either motor, sensory or both.
Each cranial nerve is identified by both a roman numeral and name:
The number indicates
The name designates
The number indicates order, from anterior to posterior in which they originate within the brain
The name designates the nerve distribution or function
Cranial Nerve 1
Olfactory [I] CEREBRUM Sensory Olfaction (smell)
Cranial nerve 2
Optic [II] CEREBRUM Sensory Vision (sight)
Cranial nerve 3
Oculomotor [III] MIDBRAIN Motor Movement of eyeball and upper eyelid
Constriction of pupil
Cranial nerve 4
Trochlear [IV] MIDBRAIN Motor Movement of eyeball
Cranial nerve 5
Trigeminal [V] PONS BOTH Sensory Motor Facial sensation
Mastication (chewing)
Cranial nerve 6
Abducens [VI] PONS Motor Movement of eyeball
Cranial nerve 7
Facial [VII] PONS BOTH Sensory Motor Gustation (anterior 2/3 tongue)
Muscles of facial expression
Cranial nerve 8
Vestibulocochlear [VIII] MEDULLA Sensory
Equilibrium (Vestibular branch)
Hearing (Cochlear branch)
Cranial nerve 9
Glossopharyngeal [IX] MEDULLA BOTH Sensory Motor Gustation (posterior 1/3 tongue)
Assists in swallowing
Cranial nerve 10
Vagus [X] Note: has wide distribution outside of head and neck MEDULLA BOTH Sensory Motor Gustation (epiglottis/pharynx) Monitors blood pressure, O2 and CO2 levels Swallowing, coughing Motility and secretion of GI organs
Cranial nerve 11
Accessory [XI] MEDULLA Motor Movement of head, pectoral girdle
Cranial nerve 12
Hypoglossal [XII] MEDULLA Motor Movement of tongue, speech
