Cranial nerves Flashcards
Olafactory nerve
CN I: Provides sense of smell by innervating the olafactory mucosa in the nasal cavity
Optic nerve
CN II: Purely sensory nerve that provides sense of vision.
Its axons start from retina of eye and meet at the optic chiasma.
Nerves exchange axons before diverging to form optic track
Oculomoter nerve
CN III: A motor cranial nerve
Innervates four of the six eye muscles and adjustment called accomadation
Trochlear nerve
CN IV: A small motor nerve that innervates one of the six extrinsic muscles that moves the eyeball
Trigeminal nerve
CN V: A large mixed nerve with 3 branches that provide innervation from the face and motor innervation to the muscle for chewing
Abducens nerve
A small motor nerve that innervates the final extrinsic eye muscle
Facial nerve
CN VII: Innervates:
facial expression
2/3 taste of the tongue
Motor to lacrimal glands (produces tears)
Mucous and saliva
Sensory parts of the mouth
Vestibulocochlear nerve
CN VIII: Innervates the structure of the inner ear and provides hearing and equilibrium
Glossopharyngeal nerve
CN IX: Provides motor axons to the muscles of the pharynx. Swallowing and the posterior 1/3 of the taste of the tongue
Vagus nerve
CN X: Only cranial nerve that “wanders” outside of the head of the neck
It provides sensory innervation from the skin of the head and pharynx
Motor axons to muscles involved in speech, swallowing, and some salivary glands.
Outside of the head and neck it innervates most of the thoracic and abdominal viscera as the main nerve of the parasympathetic nervous system
Accessory nerve
CN XI: Only cranial nerve that has both a cranial component originating from the brain stem and a spinal component originating from spinal cord. Its motor axons innervate the muscles that move the head and neck
Hypoglossal nerve
Small motor nerve that innervates the tongue, but doesn’t provide any taste
