Cranial Nerves I Flashcards
1
Q
Cranial Nerve Modalities: Somatomotor
A
- GSE
- Skeletal mm. of tongue and eye (extrinsic)
2
Q
Cranial Nerve Modalities: Visceromotor
A
- GVE
- Only parasympathetic travel with CN to smooth and cardiac mm.
- Visceral glands, salivary and lacrimal glands, mucus glands and membranes
3
Q
Cranial Nerve Modalities: Branchiomotor
A
- SVE
- Skeletal mm. of the branchial arches
- e.g.- mm of mastication, facial expression, pharynx (swallowing), larynx (speech)
4
Q
Cranial Nerve Modalities: Somatosensory
A
- GSA
- Touch, temp., pain receptors in skin, oral and nasal cavities, and pharynx
5
Q
Cranial Nerve Modalities: Viscerosensory
A
- GVA
- Stretch receptors of the gut
- Baroreceptors of the carotid and aortic bodies
- Chemoreceptors of gut and carotid body
6
Q
Cranial Nerve Modalities: Special Sensory
A
- SSA- vision, hearing, and balance
- SVA- smell and taste
7
Q
Innervation Chart
A
8
Q
CN I
A
- Olfactory N.
- SVA
- Sensation of olfaction (smell)
- Not a true nerve, but a nerve tract (composed of 2o sensory neurons in olfactory bulb)
- 1o neurons are receptor cells in epithelial lining nasal cavity, axons pierce cribriform plate of ethmoid bone
- CN I is outgrowth of cerebrum
9
Q
The Orbit
A
- Bony margin (7 bones)
- Frontal
- Ethmoid
- Lacrimal
- Maxillary
- Palatine
- Sphenoid
- Zygomatic
10
Q
The Orbit: Contents
A
- Eyeball
- Extraoccular muscles
- Nerves
- CN II, III, IV, V1, V2, and VI
- Sympathetic nerves in ciliary nerves
- Vasculature: opthalmic artery, retinal artery, superior and inferior opthalmic veins
- Lacrimal gland
- Extraoccular fat
11
Q
Innervation of the Orbit
A
- Special sensory (SSA): (CN II) retina
- Somatosensory (GSA): (CN V1) eyeball
- Somatomotor (GSE): (CN III, IV, VI) 6 extra-ocular muscles (4 rectus, 2 oblique), and levator palpebrae superioris
- Visceromotor (GVE): (CN III, VII) 3 intrinsic muscles (sphincter pupillae, dilator pupillae, ciliary muscles, CN III), superior tarsal muscles (sympathetic), lacrimal gland (CN VII)
12
Q
The Eyeball
A
- cornea: transparent covering to anterior eye
- iris: controls pupillary diameter, determines eye color
- pupil: a hole in the center of the iris that allows light in
- lens: refracts light to focus image on retina
- ciliary body: controls the shape of the lens
- sclera: connective tissue covering to eye
- retina: detects images through photoreceptors, sends signal to CN II
13
Q
CN II
A
- Optic N.
- SSA
- Not a true nerve, but a nerve tract (composed of axons of 2o sensory neurons)
- 1o neurons are receptor cells (photoreceptors=rods and cones) in retina
- Outgrowth of diencephalon
14
Q
Optic nerve between
A
Chiasm and retina
15
Q
Optic chiasm
A
Where optic n. fibers from the nasal side of the retina (lateral visual field) cross over to the contralateral side of the brain
16
Q
Optic tract
A
Between chiasm and thalamus