Cranial Nerves Flashcards
Cranial Nerve I
•olfactory •skull foramen: cribriform plate •efferent: NA •afferent special sensory: -fiber type: special sensory -sensory ganglion: olfactory mucosareceptor cells -area supplied: olfactory mucosa
Cranial Nerve II
•Optic •skull foramen: optic •efferent: NA •afferent special sensory: -fiber type: special sensory -sensory ganglion: ganglion layer of the retina -area supplied: neural retina
Special Sensory Fibers
Cell bodies are in the special sense organs rather than in a sensory ganglion similar to the dorsal root ganglion of the spinal cord as is typical for somatic and visceral afferent elsewhere
Somatic Effernet/Motor
These are the same as the motor fibers that innervation skeletal muscle from the spinal cord. The motor fibers of cranial nerves innervation skeletal muscles of the eye, jaw, face, neck and tongue
Cranial Nerve III
•Oculomotor
•skull foramen: superior orbital fissure
•efferent somatic motor and parasympathetic motor:
-fiber type: somatic, parasympathetic
-motor nuclei: oculomotor nucleus
-parasympathetic ganglion: ciliary
-area supplied motor: extrinsic eye muscles (superior, medial, inferior recti and levator palpebrae superioris which opens the eye but DOES NOT close it) except lateral rectus and superior oblique
-area supplied parasympathetic: sphincter and ciliary muscles - focus on close objects, lens lubrication, pupil constriction
•afferent: NA
Cranial Nerve IV
•Trochlear •skull foramen: superior orbital fissure •efferent somatic motor: -fiber type: somatic -motor nuclei: trochlear nucleus -area supplied: superior oblique muscle •afferent: NA
Cranial Nerve V
- trigeminal
- skull foramen: Superior orbital fissure, foramen rotundum, foramen ovale
- V1 (sensory), V2 (sensory), V3 (somatic motor, sensory)
Cranial Nerve V: V1
•opthalmic •skull foramen: superior orbital fissure •efferent: NA •afferent: -fiber type: somatic sensory -sensory ganglion: trigeminal -skin of face, cornea (blink reflex)
Cranial Nerve V: V2
•maxillary •skull foramen: foramen rotundum •efferent: NA •afferent: -fiber type: somatic -sensory ganglion: trigeminal -area supplied: skin of face, upper teeth, nasal cavity
Cranial Nerve V: V3
•mandibular •skull foramen: foramen ovale •efferent: -fiber type: somatic (arch 1) -motor ganglion: NA -area supplied: muscles of mastication, tensor tympani, tensorpalatini (close jaw) ; anterior digastric, mylohyoid (open jaw) •afferent -fiber type: somatic -sensory ganglion: trigeminal -area supplied: skin of face, lower teeth, anterior 2/3 of tongue
Cranial Nerve VI
•abducens •skull foramen: superior orbital fissure •efferent somatic motor: -fiber type: somatic -motor nuclei: abducens nucleus -area supplied: lateral rectus muscle •afferent: NA
Cranial Nerve VII
•facial: greater petrosal, chordates tympani, terminal
Cranial Nerve VII: greater petrosal
•facial
•skull foramen: internal acoustic meatus, pterygoid canal
•efferent parasympathetic motor:
-fiber type: parasympathetic
-motor nucleus: superior salivary nucleus
-ganglion: pterygopalatine ganglion
-area supplied: lacrimal, nasal
Cranial Nerve VII: chorda tympani
•facial •skull foramen: petrotympanic fissure •efferent parasympatheic motor: -fiber type: parasympathetic -motor ganglion: submandibular -area supplied: secretory function to submandibular and sublingual salivary glands (NOT parotid) •afferent special sensory: -fiber type: visceral -sensory ganglion: geniculate -area supplied: taste, anterior 2/3 tongue
Cranial Nerve VII: terminal (temporal, zygomatic-buccaneers and mandibular cervical)
•facial
•skull foramen: stylomastoid, internal acoustic meatus
•efferent somatic motor:
-fiber type: branchial (arch 2), somatic motor
-motor nucleus: facial motor nucleus
-area supplied: facial expression, posterior belly of digastric (depression of jaw, causes mouth to open), eye closing
•efferent parasympathetic motor:
-fiber type: parasympathetic
-parasympathetic ganglion: submandibular ganglion
-area supplied: stapedius (stabilises stapes), stylohyoid (draws hyoid backwards, elevates tonsils)
Cranial Nerve VIII
•vestibulocochlear
•skull foramen: internal acoustic meatus
•efferent: NA
•afferent special sensory:
-fiber type: special sensory, bipolar
-sensory ganglion: spiral (cochlear) and vestibular (vestibular apparatus)
-area supplied: organ of Corti semicircular canals, saccule, utricle - hearing and equilibrium
Cranial Nerve IX
•glossopharyngeal
•skull foramen: jugular
•efferent somatic and parasympathetic motor
-fiber type: somatic and parasympathetic, branchial (arch 3)
-motor ganglion parasympathetic: otic
-parasympathetic area supplied: parotid gland, stylopharyngeus muscle
-motor nucleus: nucleus ambiguus
-somatic motor area supplied: stylopharyngeus - elevation of pharynx and larynx during swallowing
•afferent sensory and special sensory:
-fiber type: visceral
-sensory ganglion: inferior, inferior/superior
-area supplied: special -taste on posterior 1/3 tongue, general touch, pain, temperature -external ear, posterior 1/3 tongue, pharynx, s. palate, middle ear, blood pressure and O2/CO2 levels from baroreceptors and chemoreceptors
Cranial Nerve X
•vagus
•skull foramen: jugular
•efferent parasympathetic, motor:
-fiber type: parasympathetic and motor, branchial (arch 4, arch 6)
-parasympathetic nucleus: near organs
-area supplied: thoracic and abdominal viscera to left colic flexure
-somatic nucleus: nucleus ambiguus
-somatic area supplied: skeletal muscle of palate (palatoglossus), pharynx, larynx, esophagus swallowing and speaking
•afferent sensory:
-fiber type: visceral, sensory
-sensory ganglion: inferior and superior ganglion
-area supplied: viscera supplied by visceral fibers, taste on epiglottis, posterior half of outer ear canal
Cranial Nerve XI
•accessory or spinal accessory •skull foramen: jugular •efferent somatic motor: -fiber type: somatic -motor ganglion: NA -area supplied: trapezius, sternocleidomastoid muscles •afferent: NA
Cranial Nerve XII
•hypoglossal •skull foramen: hypoglossal canal •efferent somatic motor: -fiber type: somatic -motor nucleus: hypoglossal nucleus -area supplied: intrinsic and extrinsic muscles of tongue
Somatic efferent
Motor to skeletal muscle (derived from somites)
Visceral efferent
Motor to smooth muscles and glands = parasympathetic
Branchial Effernet
Motor to skeletal muscle (derived from branchial/pharyngeal arches)
Special sensory
Smell, sight, hearing, balance
Somatic afferent
Touch, pain, temperature, propiception for skin and mucosa of head(to ectodermal derivatives)
Branchial or Visceral afferent
Baroreceptors, stretch, chemo and mechanical receptors including taste (to mesodermal and endodermal derivatives)
Branchial Arch 1
- Trigeminal V3
- muscles of mastication, anterior belly of the digastric, tensor tympani
- incus, malleus, part of the mandible
Branchial 2
- Facial VII
- muscles of facial expression, posterior belly of the digastric, stylohyoid, stapedius
- stapes, styloid process, part of the hyoid
Branchial Arch 3
- Glossopharygeal IX
- stylopharyngeus
- part of the hyoid
Branchial Arch 4
- Vagus X
- muscles of the pharynx and larynx
- laryngeal cartilages
Pharyngeal Pouch 1
•auditory tube
Pharyngeal Pouch 2
•palatine tonsil
Pharyngeal Pouch 3
•inferior parathyroid glands, thymus
Pharyngeal Pouch 4
•superior parathyroid glands, parafollicular cells of the thyroid
Pharyngeal Cleft 1
- external acoustic meatus
* the thin strip of tissue between the first cleft and first cleft = tympanic membrane
Special Sensory with Cell Bodies in the Sense Organ
I, II, VIII
Motor to Intrinsic Muscles of the Eye
III, IV, VI
Branchial Arches CN
Motor and sensory
V, VII, IX, X
Motor to the Neck and Tongue Muscles
XI, XII
Parasympathetic to the Glands of the Head
III, VII, IX, X
MNP + MNP=
Philtrum and development of palate
Philtrum + MPs =
Upper lip
Frontonasal prominence
Unpaired
Forehead
LNP + MNP =
Nose
MP + MP =
Cheeks
Mandibular Prominence + Mandibular Prominence =
Jaw
Branchial Arches
- each arch is composed of a mesenchymal (mesoderm and neural crest) core covered on the inside by endoderm and on the outside by ectoderm
- the mesenchyme develops into bones, cranial nerves and the muscles of the face and neck; each arch is associated with a single cranial nerve
- each arch is associated with a branch of the aorta or the aorta itself, several of which wil become the major arterires of the neck or upper thorax (aorta and carotids)
