Lecture 12: Brain and Cranial Nerves e.) Cranial Nerves
Accessory Nerve XI: Orgin
cranial root: motor nuclei in medulla spinal root: spinal cord (C1 - C5 segments)
Hypoglossal Nerve XII: Pathway
hypoglossal canals of occipital bone
Vagus Nerve X: Primary Function
mixed (sensory and motor) of thorax and abdomen
Facial Nerve VII: Primary Function
mixed (sensory and motor) to face
Glossopharyngeal Nerve IX: Primary Function
mixed (sensory and motor) to head and neck
Hypoglossal Nerve XII: Primary Function
motor (tongue movements)
Hypoglossal Nerve XII: Origin
motor nuclei in medulla oblongata
Accessory Nerve XI: Primary Function
motor to muscles of neck and upper back
Hypoglossal Nerve XII: Destination
muscles of tongue
Trigeminal Nerve V: Pathway
ophthalmic branch: superior orbital fissure maxillary branch: foramen rotundum mandibular branch: foramen ovale
Vestibulocochlear Nerve VIII: Origin
receptors of inner ear
Trigeminal Nerve V: Destination
sensory nerves: sensory nuclei in pons motor nerves of mandibular branch: muscles of mastication
Vagus Nerve X: Origins
sensory: part of pharynx auricle and external acoustic canal diaphragm visceral organs of thoracic, and abdominopelvic cavities motor: motor nuclei in medulla oblongata
Glossopharyngeal Nerve IX: Origins
sensory: posterior 1/3 of tongue part of pharynx and palate carotid arteries motor: motor nuclei in medulla oblongata
Vagus Nerve X: Destination
sensory: sensory nuclei and autonomic centers in medulla oblongata motor: palate, pharynx digestive, respiratory, and cardiovascular systems in thoracic and abdominal cavities
Glossopharyngeal Nerve IX: Destination
sensory: sensory nuclei in medulla oblongata somatic motor: muscles involved in swallowing visceral motor: parotid salivary gland
Facial Nerve VII: Destination
sensory: sensory nuclei in pons somatic motor: muscles of facial expression visceral motor: lacrimal and nasal mucous glands submandibular and sublingual salivary glands
Facial Nerve VII: Origins
sensory: taste receptors on anterior 2/3 of tongue motor: motor nuclei in pons
Oculomotor Nerve Destination
somatic motor: superior, inferior, and medial rectus muscles inferior oblique muscle levator palpebrae superioris muscle visceral motor: intrinsic eye muscles
Vestibulocochlear Nerve VIII: Primary Function
special sensory vestibular branch: balance and equilibrium cochlear branch: hearing
Vestibulocochlear Nerve VIII: Destination
vestibular and cochlear nuclei in pons and medulla oblongata
How to identify Cranial Nerves?
Each one is identified by: primary function, origin, pathway, destination
What are the 12 Cranial nerves
I) Olfactory II) Optic III) Oculomotor IV)Trochlear V) Trigeminal VI) Abducens VII) Facial VIII) Vestibulocochlear IX) Glossopharyngeal X) Vagus XI) Accessory XII) Hypoglossal
What are the three cranial nerves for special senses?
I, II, VIII for smell sight hearing and balance
What are the motor cranial nerves?
III, IV, VI, XI, XII
Trigeminal Nerve V
Primary function: mixed (sensory and motor) to face Origins: ophthalmic branch (sensory) maxillary branch (sensory) mandibular branch (mixed)
Trochlear Nerve IV
Primary function: motor (eye movements) Origin: midbrain Pathway: superior orbital fissure of sphenoid Destination: superior oblique muscle
Oculomotor Nerve (III)
Primary function: motor (eye movements) Origin: midbrain Pathway: superior orbital fissures of sphenoid
Abducens Nerve VI
Primary function: motor (eye movements) Origin: pons Pathway: superior orbital fissures of sphenoid Destination: lateral rectus muscle
Optic Nerve (II)
Primary function: special sensory (vision) Origin: retina of eye Pathway: optic canals of sphenoid Destination: diencephalon via optic chiasm
Olfactory Nerve (I)
Primary function: special sensory (smell) Origin: receptors of olfactory epithelium Pathway: olfactory foramina in cribriform plate of ethmoid Destination: olfactory bulbs
Facial Nerve Branches
Temporal Zygomatic Buccal Mandibular Cervical
What are the mixed cranial nerves?
V, VII, IX, X
Vestibulocochlear Nerve VIII: Pathway
internal acoustic canals of temporal bones
Facial Nerve VII: Pathway
internal acoustic canals to facial canals (stylomastoid foramina)
Accessory Nerve XI: Destination
internal branch: voluntary muscles of palate, pharynx, and larynx external branch: sternocleidomastoid and trapezius muscles
Accessory Nerve XI: Pathway
jugular foramina between occipital and temporal bones
Glossopharyngeal Nerve IX: Pathway
jugular foramina between occipital and temporal bones
Vagus Nerve X: Pathway
jugular foramina between occipital and temporal bones