Chapter 26: Trigeminal Nerve Flashcards
The Vth cranial nerve is called the trigeminal nerve because it has _____ major divisions.
- 3
The superior division is called the ophthalmic nerve because it is the sensory nerve of the _____ socket and the skin above it.
- Eye
The middle division of the trigeminal nerve is called the maxillary nerve because it is the sensory nerve of the area of the face overlying the _____ bone.
- Maxillary
The ophthalmic and maxillary nerves are divisions of the _____ or _____ cranial nerve.
- Trigeminal
- Vth
The _____ nerve is the sensory nerve of the upper third of the face and the _____ nerve is the sensory nerve of the middle third of the face.
- Ophthalmic
- Maxillary
The ophthalmic and maxillary nerves are purely sensory and have no _____ component.
- Motor
The lowest division of the trigeminal nerve is called the mandibular nerve because it is the sensory nerve of the region around the _____.
- Mandible
The three divisions of the trigeminal nerve are the _____, _____, and _____ nerves.
- Ophthalmic
- Maxillary
- Mandibular
Unlike the _____ and _____ nerves, the mandibular nerve has a significant motor component.
- Ophthalmic
- Maxillary
The motor fibers in the _____ nerve innervate the muscles that move the mandible.
- Mandibular
The temporalis and masseter, which close the mouth, the mylohyoid and anterior belly of the digastric, which open the mouth, and the medial and lateral pterygoid muscles, which move the jaw from side to side, are all innervated by the _____ nerve.
- Mandibular
Although it assists with chewing, the buccinator muscle is not innervated by the mandibular nerve because it does not move the _____.
- Mandible
The tensor tympani muscle is the only muscle innervated by the mandibular nerve that does not move the _____.
- Mandible
A tiny branch of the mandibular nerve enters the middle ear through the wall of the Eustachian tube and innervates the _____ muscle.
- Tensor tympani
Contraction of the tensor tympani makes it harder for the malleus to move and _____ sound.
- Deadens (muffles/attenuates)
Reflex contraction of the tensor tympani during chewing _____ the _____ of chewing.
- Muffles
- Sound
The motor fibers in the mandibular nerve are _____ of _____ neurons in the motor nucleus of the trigeminal nerve
- Axons
- Lower motor
Although the sensory nuclei of the trigeminal nerve extend throughout the brainstem, the _____ nucleus is confined to the mid-pontine level.
- Motor
The motor nucleus of the trigeminal nerve is just medial to the principal sensory nucleus of the trigeminal nerve at the _____ level.
- Mid-pontine
The principal sensory nucleus of the trigeminal is the most lateral nucleus in the brainstem at the _____ level.
- Mid-pontine
Motor axons from the motor nucleus of the trigeminal nerve pass through the foramen ovale along with the sensory fibers of the _____ to innervate the tensor tympani and the muscles that move the mandible.
- Mandibular nerve
The motor division of the trigeminal nerve also contains muscle and tendon stretch fibers that are peripheral branches of axons of primary _____ neurons in the upper pons and midbrain.
- Sensory
The muscle and tendon stretch neurons for the jaw muscles are in the _____ and _____.
- Upper pons
- Midbrain
The primary sensory neurons for muscle and tendon stretch in the jaw muscles are collectively called the mesencephalic nucleus of the trigeminal nerve because most of them are in the _____.
- Midbrain (mesencephalon)
The mesencephalic nucleus of the trigeminal nerve extends throughout the _____ and midbrain.
- Upper pons
The _____ of the trigeminal nerve contains the primary sensory neurons for in jaw muscles and their tendons and the periodontal ligament.
- Mesencephalic
The peripheral branches of the axons of neurons in the mesencephalic nucleus of the trigeminal nerve innervate muscle spindles and Golgi tendon organs in the _____ and corpuscles of Ruffini in the _____.
- Jaw muscles
- Periodontal ligament
The _____ of the _____ is the only place where primary sensory neurons are found in the central nervous system.
- Mesencephalic nucleus
- Trigeminal nerve
The mesencephalic nucleus of the trigeminal contains only _____ sensory neurons for muscle, tendon, and ligament stretch in the chewing apparatus.
- Primary
The peripheral branches of the axons of the _____ neurons in the mesencephalic nucleus of the trigeminal nerve descend in the mesencephalic tract of the trigeminal nerve.
- Primary sensory
The myelinated peripheral branches of axons of neurons in the mesencephalic nucleus of the trigeminal nerve form the _____ of the _____ lateral to the mesencephalic nucleus.
- Mesencephalic tract
- Trigeminal nerve
Most central branches of the axons of the _____ and _____ neurons in the mesencephalic nucleus of the trigeminal nerve end in the motor nucleus of the trigeminal nerve.
- Muscle
- Tendon stretch