4.1 The Skull & Cranial Nerves Flashcards
What are the two types of bones that form the skeleton of the head
Neurocranium
Viscerocranium
Bones that house the brain
Neurocranium
The facial bones
Viscerocranium
What are the two main categories of neurocranium bones
Calvaria (skull cap) Cranial base (basicranium)
The viscerocranium are facial bones that form
Orbits
Nasal cavities
Upper jaw
Lower jaw (mandible)
What are the specific bones of the neurocranium
Frontal 2 parietal 2 temporal Occipital Sphenoid Ethmoid
What are the four sutures of the neurocranium
Coronal
Lambdoid
Sagittal
Squamous
The coronal suture separates
Frontal and parietal
The lambdoid suture separates
Parietal and occipital
The Sagittal suture separates
Right and left parietal
The squamous suture separates
Parietal and temporal
What are the five intersections of cranial sutures
Bregma Lambda Pterion Asterion Nasion
The bregma intersects
Sagittal and coronal sutures
The lambda intersects
The lambdoid and Sagittal sutures
The pterion intersects
The frontal
Parietal
Temporal
And sphenoid bones
The asterion intersects
Parietal
Occipital
And temporal bones
The nasion intersects
The frontal and nasal bones
What is the most anterior part of the forehead
Glabella
What is the superiormost point of the neurocranium
Vertex
What is the most prominent point of external occipital protuberance
Inion
What cranial fossa and what bone is the cribriform plate in
Anterior fossa
Ethmoid bone
What cranial fossa and what bone is the optic foramen in
Middle fossa
Sphenoid bone
What cranial fossa and what bone is superior orbital fissure in
Middle fossa
Sphenoid bone
What cranial fossa and what bone is foramen rotundum in
Middle fossa
Sphenoid bone
What cranial fossa and what bone is foramen ovale in
Middle fossa
Sphenoid bone
What cranial fossa and what bone is foramen spinosum in
Middle fossa
Sphenoid bone
What cranial fossa and what bone is foramen lacerum in
Middle fossa
Sphenoid bone
What cranial fossa and what bone is the internal acoustic meatus in
Posterior fossa
Temporal bone
What cranial fossa and what bone is the jugular foramen in
Posterior fossa
Between temporal and occipital
What cranial fossa and what bone is the hypoglossal canal in
Posterior fossa
Occipital bone
What cranial fossa and what bone is the foramen magnum in
Posterior fossa
Occipital bone
The sphenoid, ethmoid, and frontal bone form part of
The anterior cranial fossa
The sphenoid bone compromises the floor of the
Middle cranial fossa
What holds the pituitary gland within it
The sella turcica
The sphenoid bone articulates with how many other bones
8
The sphenoid bone has a central body, what does it have laterally and inferiorly
Two wings laterally
Two processes inferiorly
What specific bones make up the viscerocranium (14)
2 lacrimal 2 nasal 2 maxillae 2 zygomatic 2 palatine 2 inferior nasal conchae Mandible Vomer
Bones of the nasal cavity
Nasal Maxillae Inferior nasal conchae Ethmoid Vomer
The ethmoid is made up of
Middle nasal concha
Superior nasal concha perpendicular plate
The central nervous system comprises the
Brain and spinal cord
The peripheral nervous system consists of
Sensory and motor neurons
Ganglia
Nerves
Nerves originating from brain or brain stem and exiting through foramina or fissures in the cranium
Cranial nerves
Cranial nerves carry nerve fibers for
Somatic motor
General sensory
Special sensory
Parasympathetic motor
Movement of eyes, mastication, deglutition, respiration, vocalization, facial expression
Somatic motor
Pain, pressure, temperature (to tissues)
General sensory
Olfaction, vision, gustation, audition, equilibrium
Special sensory
To lacrimal, salivary, and mucous glands and smooth muscles of eyes
Parasympathetic motor
CN 1 name
Olfactory nerve
CN1 function and exit
Olfactory nerve
F: special sensory- smell
E: cribriform plate of ethmoid
CN1 innervates
Olfactory nerve
Olfactory epithelium of superior nasal cavity
CN2 function and exit
Optic nerve
F: special sensory-vision
E: optic foramen
CN 2 innervates
Optic nerve
Retina of eye
The optic nerve of each eye sees what visual field
Temporal field and nasal field
The optic chiasm affects with visual field
Decussation of temporal fields of view
Visual fields of the optic tracts
The left: info from right fields of both eyes
The right: info from left fields of both eyes
If the right optic nerve was defected it would cause
Blindness of one eye
A defect at the optic chiasm causes
Loss of peripheral visual fields, tunnel vision
A defect at the optic tract caused
Loss of visual field on opposite side of both eyes
Blindness of one eye
Anopsia
Tunnel vision
Bitemporal hemianopsia
What are the visual fields of the retina
Nasal (medial)
Temporal (lateral )
CN3 exits
Occulomotor nerve
Superior orbital fissure of sphenoid
CN3 function/innervation
Oculomotor nerve
Somatic motor- all eye muscles except superior oblique and lateral rectus
Parasympathetic- constriction of pupils, change shape of lens
Muscle that raises eyelids
Levator palpebrae superioris
Complete paralysis of CN3 oculomotor leads to
Dilated pupils
Ptosis (droopy eyelids)
Inability to move eye upwards, downward, and medially
CN4 function and exit
Trochlear nerve
F: somatic motor- eye movement
E: superior orbital fissure if sphenoid
CN4 innervates
Trochlear nerve
Superior oblique muscle of eye
Injury to CN4 trochlear results in
Unable to look downward and inward
CN6 function and exit
Abducens nerve
F: somatic motor- eye movement
E: superior orbital fissure of sphenoid
CN6 innervates
Abducens nerve
Lateral rectus muscle
Injury to CN6 abducens results in
Inability to abduct the eye
Three divisions of CN5 trigeminal
V1 opthalmic
V2 maxillary
V3 mandibular
V1 division of trigeminal function and exit
V1 ophthalmic
F: general sensory
E: superior orbital fissure of sphenoid
V1 division of trigeminal innervates
V1 opthalmic
Conjunctiva and cornea of eye
Nasal cavity
Skin of scalp, forehead, eyebrows, upper eyelid, and part of external nose
V2 division of trigeminal function and exit
V2 maxillary
F: general sensory
E: foramen rotundum (sphenoid)
V2 division of trigeminal innervation
V2 maxillary
Lower eyelid, upper lip, gums, teeth, cheek, palate, and pharynx
Branches of V1 opthalmic trigeminal
Lacrimal nerve
Frontal nerve
What does the frontal nerve divide into
Supraorbital nerve
Supratrochlear nerve
V2 maxillary trigeminal branches into
Superior alveolar nerve
Infraorbital nerve
V3 division of trigeminal function and exit
Mandibular
F: general sensory, somatic motor
E: foramen ovale
V3 division of trigeminal innervates
Mandibular
Sensory- skin over mandible, lower gums, teeth, lower lip, anterior 2/3 of tongue
Motor- muscles of mastication, anterior digastric, mylohyoid, and tensor veli palantini
V3 mandibular trigeminal branches
Lingual nerve
Inferior alveolar nerve
Mental nerve
CN7 exit
Facial nerve
Through the internal acoustic meatus
Out of the stylomastoid foramen
CN 7 function/ innervation
Facial nerve
Parasympathetic- lacrimal gland, mucous glands, pharynx, palate,submandibular gland, sublingual salivary gland
Special sensory- taste receptor on anterior 2/3 of tongue
Somatic motor- muscles of facial expression, stylohyoid, posterior digastric
CN8 function and exit
Vestibulocochlear
F: special sensory- balance and hearing
E: internal auditory meatus of temporal bone
CN 8 innervates
Vestibulocochlear nerve
Vestibule
Cochlea
Receptors for motion and balance
Vestibule
Hearing receptor
Cochlea
The CN8 vestibulocochlear nerve splits into
Cochlear nerve
Vestibular nerve
If cochlear nerve is injured it results in
Tinnitus (ringing, buzzing) and deafness
If the vestibular nerve is injured it results in
Vertigo and nystagmus
CN9 exit
Glossopharyngeal nerve
Jugular foramen
Sensory part of gag reflex
Glossopharyngeal nerve CN9
CN9 function/innervation
Glossopharyngeal nerve
General sensory- poster 1/3 of tongue, pharynx, palate, tonsil
Special sensory- posterior 1/3 of tongue (taste), carotid body (monitors blood oxygen levels), carotid sinus (monitors blood pressure)
Parasympathetic- parotid gland (salivary)
Somatic motor- stylopharyngeus
CN10 exit
Vagus nerve
Jugular foramen
Motor part of gag reflex
Vagus nerve CN10
CN10 function/ innervation
Vagus nerve
Motor- muscles of pharynx, larynx, and palate (except tensor veli palantini)
General sensory- pharynx, tongue
Special sensory- taste to area around epiglottis
Parasympathetic- abdominal and thoracic viscera
CN11 function and exit
Spinal accessory nerve
F: motor
E: jugular foramen
CN11 innervates
Spinal accessory nerve
Sternocleidomastoid and trapezius
CN12 function and exit
Hypoglossal nerve
F: motor-tongue muscles
E: hypoglossal canal
CN12 innervates
Hypoglossal nerve
All muscles with gloss in the name except palatoglossus
