Lesson 15 Cranial Nerves Flashcards
Where would you find the cell bodies of sensory neurons of the cranial nerves?
Cranial Nerve Ganglia
Where do the cranial nerves and spinal nerves emerge from?
cranial nerves emerge from the area of the brain stem
Spinal nerves emerge from the spinal cord
Cranial nerve I is?
Olfactory
Cranial nerve II is
Optic
Cranial nerve III is
Oculomotor
CN iV
Trochlear
CN V -
Trigeminal
CN VI -
Abducens
CN VII
Facial
CN VIII
Vestibulocochlear
CN IX -
Glossopharyngeal
CN X -
Vagus
CN XI -
Spinal accessory
CN XII
Hypoglossal
The Olfactory Nerve (CN I) runs from the _______ to the ______ in the frontal lobe
The Olfactory Nerve (CN I) runs from the Olfactory epithelium to the Olfactory Bulb in the frontal lobe
The Olfactory Nerve (CN I)
- mixed, motor, or sensory?
- Responsible for?
Purely sensory
Responsible for Smell
The only sensory system that bypasses the thalamus is:
The Olfactory system
Where does the olfactory tract synapse?
Primary olfactory cortex (temporal lobe)
Anosmia is:
Hyposmia:
Anosmia = lack of smell
Hyposmia = decrease in ability to smell
Optic Nerve (CNII) cell bodies arise from?
The retina
The axons of what neurons join to become the Optic nerve?
Retinal ganglion cell neurons
What happens at the optic chiasm?
Half of the axons of the optic nerve cross over.
What is the optic nerve called after the chiasm?
Optic Tract (collection of axons in the CNS = tract)
Where does the optic tract synapse?
Lateral geniculate nucleus
Axons from the Lateral geniculate nucleus (called _________) synapse on the _________
Axons from the Lateral geniculate nucleus (called Optic Radiations) synapse on the P_rimary Visual Cortex_
Which CN’s control the muscles of the eye?
CN III - Oculomotor
CN IV - Trochlear
CN VI - Abducens
How many of the 6 eye muscles does the Oculomotor Nerve control?
4/6 and also the levator palpebrae superioris (eyelid)
Is oculomotor mixed, sensory or motor?
Mixed Somatic motor and parasympathetic (constrict pupil and accomodation)
What does LR6SO4 mean?
The lateral rectus is innervated by CN VI
The Superior Oblique is innervated by CN IV
What is opthalmoplegia?
Damage to the CN III which results in weakened or paralyzed eye movements
Which is the smallest CN?
Trochlear
Is the trochlear nerve mixed, sensory or motor?
Purely motor
Innervates Superior Oblique
Is CN VI (abducens) motor, sensory or mixed?
Purely Motor
The longest intracranial course of the cranial nerves is:
Abducens
What muscle is innervated by CN VI (abducens)?
Lateral rectus
Damage to the Abducens Nerve results in?
unopposed action of medial rectus = eye deviates medially
Double-vision (diplopia)
Where would you find the sensory cell bodies of the trigeminal nerve?
Trigeminal ganglion
CN V (trigeminal) has 3 branches:
V1:
V2:
V3:
CN V (trigeminal) has 3 branches:
V1: Opthalmic
V2: Maxillary (what is frozen at the dentist when working on upper teeth)
V3: Mandibular (frozen when getting work done on bottom teeth)
Is CN V (trigeminal) sensory, motor or mixed?
What are each of the 3 branches?
Mixed
V1 = pure sensory (eye)
V2 = Pure sensory (cheek)
V3 = motor + sensory (mandible)
Which three cranial nerves use CN V (trigeminal) as a conduit for parasympathetic functions?
CNs III, VII and IX
What is a common disease of the trigeminal nerve?
Trigeminal neuralgia = chronic pain in cheek and jaw region (mainly v2 and v3)
The trigeminal nerve emerges from:
Pons of the brainstem
The supraorbital nerve are a branch from _______ and supply the ______
CN v1 (ophthalmic branch of the trigeminal nerve) and supplies the skin to the forehead and air-sinuses in the skull
Which nerve branches off of the maxillary branch of the trigeminal nerve (V2) and enters the floor of the orbit through the infraorbital foramen?
Infraorbital nerve
Which nerve senses touch in the anterior part of the tongue and branches off of the Mandibular Nerve of the trigeminal nerve (V3)?
Lingual nerve
Where does the mandibular nerve enter through?
Infratemporal fossa
Which CN supplies the muscles of mastication?
CN V3 (Mandibular nerve branch of the trigeminal nerve)
Muscles of facial expression are innervated by which nerve?
CN VII Facial Nerve
Taste on the anterior 2/3 of the tongue is sensed with the _______ nerve (branch of the Facial Nerve)
Chorda Tympani Nerve
Sensory cell bodies of the facial nerve are found in the:
Geniculate ganglion
What is the Facial nerve (CN VII) known for? (3)
Somatic motor (muscles of facial expression)
Somatic sensory (tragus of ear)
Parasympathetic (lacrimal gland (tears) of eye, taste and salivation)
Someone with bell’s palsy has damage to which nerve?
CN VII (facial) = hemifacial paralysis
Which nerve regulates the gag reflux?
Glossopharyngeal (CN IX)
CN IX (glossophryngeal) innervates what muscle?
stylopharygeus (elevates pharynx) only pharyngeal muscle that is not innervated by CN X (vagus)
Where are the cell bodies of the vagus nerve?
Medulla
Difficulty in speech and swallowing could be the result of damage to the:
Vagus nerve
Which muscles are innervated by the Vagus nerve (CN X)
Muscles of the palate, pharynx and larynx
What are the sensory functions of the vagus nerve?
Visceral afferents
CN X is the major _______ nerve
parasympathetic
Is CN XI (spinal accessory nerve) sensory, motor or mixed?
Motor only
Which nerve innervates the sternocleidomastoid and trapezius muscle?
Spinal accessory nerve (CN XI)
Weakness when shrugging, turning head to one side could be the result of damage to which nerve?
XI Spinal Accessory
The Hypoglossal nerve (CN XII) is _______ (motor, sensory or mixed) and is attached to the ______ and supplies the ______
The Hypoglossal nerve (CN XII) is motor (motor, sensory or mixed) and is attached to the medulla and supplies the muscles of the tongue
