Cranial Nerves Flashcards
(34 cards)
Describe and name functions of CN I.
Name - Olfactory Nerve
Olfaction = sense of smell
Info
- Their axons enter the skull via the olfactory foramina
Sensory
- Special sensory (smell)
Somatic Motor
- None
Automatic Motor
- None
Describe and name functions of CN II.
Name - Optic Nerve
Sensory
- Special sensory (vision)
Somatic Motor
- None
Automatic Motor
- None
Describe and name functions of CN III.
Name - Oculomotor Nerve
Info
- Originates in the midbrain
- Enters the orbit via the superior orbital fissure (sphenoid bone) and carries motor signals to some of the extrinsic eye muscles
Sensory
- None
Somatic Motor
- Extrinsic eye muscles
Automatic Motor
- Intrinsic eye muscles
Describe and name functions of CN IV.
Name - Trochlear Nerve
Info
- Originates in the midbrain
- Enters the orbit via the superior orbital fissure (sphenoid bone) and carries motor signals to one of the extrinsic eye muscles
Sensory
- None
Somatic Motor
- Extrinsic eye muscles
Automatic Motor
- None
Describe and name functions of CN V.
Name - Trigeminal Nerve
Info
- Emerges front he pons and has 3 branches
1. Ophthalmic (V1) - exits cranial cavity via superior orbital fissure
2. Maxillary (V2) - exits cranial cavity vis foramen rotundum
3. Mandibular (V3) - exits cranial cavity via foramen ovale
- V3 also carries motor signals to the muscles of mastication
Sensory
- Somatic sensations from the face
Somatic Motor
- Muscles of mastication
Automatic Motor
- None
Describe and name functions of CN VII.
Name - Facial Nerve
Info
- Emerges from the pons and exits the skull via the internal auditory meatus and stylomastoid foramen (temporal bone)
- Carry motor signals to the muscles of the facial expression
- Carry automatic (parasympathetic) signals to most of the salivary glands
Sensory
- Special sensory (taste)
Somatic Motor
- Muscles of facial expression
Automatic Motor
- Salivary Glands
Describe and name functions of CN VIII.
Name - Vestibulocochlear Nerve
Vestibular = balance
Cochlear = hearing
Info
- Has 2 branches
1. Vestibular branch - carries signals related to balance from the semicircular canals in the inner ear
2. Cochlear branch - carries signals related to hearing from the cochlea in the inner ear
- The branches merge and pass through the internal auditory meatus (temporal bone) before entering the medulla oblongata
Sensory
- Special sensory (balance)
- Special sensory (hearing)
Somatic Motor
- None
Automatic Motor
- None
Describe and name functions of CN IX
Name - Glossopharyngeal Nerve
Glossus = tongue
Pharynx = throat
Info
- Emerges from the medulla oblongata and exits the skull via the jugular foramen (temporal bone)
- Once outside the skull, the nerve splits into branches that:
- Carry motor signals to one of the muscles of the pharynx
- Carry autonomic (parasympathetic) signals to one of the salivary glands
Sensory
- Special sensory (taste)
- Visceral sensory (arotids)
Somatic Motor
- Pharynx
Automatic Motor
- Salivary gland
Describe and name functions of CN X
Name - Vagus Nerve
Info
- Emerges from the medulla oblongata and exits the skull via the jugular foramen (temporal bone)
- Once outside the skull, the nerve travels down the neck and into the thoracic cavity, splitting into branches that:
- Carry motor signals to most of the muscles of the pharynx and larynx
- Carry autonomic (parasympathetic) signals to the heart, lungs, and organs of the digestive system
- Contains axons carrying signals from receptors in the arch of the aorta
Sensory
- Visceral sensory (aorta)
Somatic Motor
- Pharynx
- Larynx
Automatic Motor
-Thoracic and abdominal organs
Describe and name functions of CN XI.
Name - Accessory Nerve
*Technically not a “cranial nerve”
Info
- Branches from the C1-C5 spinal nerves merge and enter the skull via foramen magnum (occipital bone)
- The nerve immediately turns around and exits the skull via the jugular foramen (temporal bone)
- Travels down the neck and innervates the trapezius and SCM
Sensory
- None
Somatic Motor
- Trapezius
SCM
Automatic Motor
- None
Describe and name functions of CN XII.
Name - Hypoglossal Nerve
Glossus = tongue
Info
- Emerges from the medulla oblongata and exits the skull via a small canal in the occipital bone
- Once outside the skull, it innervates the tongue muscles
Sensory
- None
Somatic Motor
- Tongue muscles
Automatic Motor
- None
Describe the origin, sensory and motor functions of CN I - Olfactory.
Origin
- Nose
Sensory
- Smell
Motor
- None
Describe the origin, sensory and motor functions of CN II - Optic.
Origin
- Eye
Sensory
- Vision
Motor
- None
Describe the origin, sensory and motor functions of CN III - Oculomotor.
Origin
- Midbrain
Sensory
- None
Motor
S: extrinsic eye muscles
A: intrinsic eye muscles
Describe the origin, sensory and motor functions of CN IV - Trochlear.
Origin
- Midbrain
Sensory
- None
Motor
- Extrinsic eye muscles
Describe the origin, sensory and motor functions of CN V - Trigeminal.
Origin
- Pons
Sensory
- Face (somatic)
Motor
- Muscles of mastication
Describe the origin, sensory and motor functions of CN VI - Abducens.
Origin
- Pons
Sensory
- None
Motor
- Extrinsic eye muscles
Describe the origin, sensory and motor functions of CN VII - Facial.
Origin
- Pons
Sensory
- Taste
Motor
S: tuscles of facial expression
A: salivary glands
Describe the origin, sensory and motor functions of CN VIII - Vestibulocochlear.
Origin
- Inner ear
Sensory
- Balance
- Hearing
Motor
- None
Describe the origin, sensory and motor functions of CN IX - Glossopharyngeal
Origin
- Medulla Oblongata
Sensory
- Taste + carotids (visceral)
Motor
S: pharynx
A: salivary gland
Describe the origin, sensory and motor functions of CN X - Vagus.
Origin
- Medulla Oblongata
Sensory
- Aorta (visceral)
Motor
S: pharynx, larynx
A: thoracic/abdominal organs
Describe the origin, sensory and motor functions of CN XI - Accessory.
Origin
- Spinal cord (C1-C5)
Sensory
- None
Motor
- Trapezius
- SCM
Describe the origin, sensory and motor functions of CN XII - Hypoglossal.
Origin
- Medulla oblongata
Sensory
- None
Motor
- Tongue muscles
Which nerve passes through the optic foramen?
CN II
