Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
27 Cards in this Set
- Front
- Back
|
How does sensation from the face, head, and neck travel back to the CNS?
|
PRIMARILY through trigeminal nerve. Small areas of skin/viscera use facial, glossopharyngeal, vagus nerves.
|
|
|
3 nuclei in the brainstem associated with the trigeminal system:
|
1) Mesencephalic nucleus of V
2) Principal (pontine/chief) sensory nucleus 3) Spinal trigeminal nucleus - divided into nucleus oralis, nucleus interpolaris, nucleus caudalis |
|
|
Nucleus oralis, nucleus interpolaris, and nucleus caudalis are divisions of the _____ nucleus. What senses do each ones carry?
|
Spinal nucleus.
Nucleus caudalis - touch, pain, termperature Nucleus oralis - pain impulses from tissues of oral cavity Nucleus interpolaris - not known |
|
|
List the ganglion associated and areas of sensory representation for
1) Trigeminal nerve 2) Facial nerve 3) Glossopharyngeal nerve 4) Vagus nerve |
1) Trigeminal ganglion, aka Gasserian/semilunar.
1a) Mario Smushed TOAD's Mushroom Cart Membranes of nose/nasal cavity Skin of face/forehead/scalp TMJ Oral cavity/teeth Anterior 2/3 of tongue Dura surrounding brain (majority) Maxillary/frontal sinuses Cornea/conjunctiva 2. Geniculate ganglion 2a) Everyone Clapped. External auditory meatus Conchae of ear 3. Superior ganglion of IX 3a) Princess Peach, Arriving Last Pharynx (upper portion) Posterior 1/3 of tongue Auditory tube (upper portion) Lateral aspect of ear (small area) 4) Superior ganglion of X Didn't Take Losing Politely & Cried Everywhere Dura of posterior cranial fossa Tympanic membrane Lower larynx and pharynx Posterior wall/floor of external auditory meatus Conchae of the ear Esophagus (upper portion) |
|
|
Describe the sensory pathway for crude touch, pain, and temperature in the head.
|
Fibers from cell bodies in the ganglia descend in the spinal tract of V -> synapse in nucleus caudalis (2nd order neurons) -> Travel up in ventral trigeminothalamic tract to contralateral thalamus (3rd order neurons) -> thalamus to somatosensory cortex of parietal lobe of the cerebrum
|
|
|
1. Damage to the spinal tract of V results in?
2. Damage to the trigeminothalamic tract results in? |
1. Ipsilateral sensory loss to the face and contralateral sensory loss in the remainder of the body (alternating hemianesthesia)
2. Contralateral sensory loss in the face |
|
|
1. Where are cell bodies associated with tactile discrimination and pressure located?
2. Describe the pathway for these sensations. |
1. Trigeminal (Gasserian, semilunar) ganglion.
2. Fibers from trigeminal ganglion -> synapse in principal sensory nucleus of V (second order) -> ascend bilaterally in dorsal ascending tract of V -> thalamus (third order neurons) -> somatosensory cortex |
|
|
1. Where do fibers for proprioception come from in the head?
2. Why is the proprioceptive pathway unique? 3. Describe the proprioceptive pathway |
1. Trigemino-proprioceptive fibers come from muscles of mastication, TMJ, and periodontal ligament around the teeth.
2. Cell bodies not found in ganglion. Found in nucleus in the midbrain (mesencephalic nucleus of V) 3. Fibers from TMJ/muscles of mastiaction/periodontal ligament around teeth -> mesencephalic nucleus of V -> motor nucleus of V This forms a reflex loop. Fibers from mesencephalic loop may also go bilaterally to thalamus and cerebellum. |
|
|
Describe the auditory pathway, starting from the middle ear.
|
Middle ear -> inner ear -> hair cells in cochlea -> spiral ganglion in temporal bone -> auditory part of vestibulocochlear nerve -> left and right cochlear nuclei
Ventral cochlear nuclei -> superior olivary nucleus (pons) -> inferior colliculus -> medial geniculate nucleus (thalamus) -> auditory cortex Dorsal cochlear nuclei -> inferior colliculus -> medial geniculate body (thalamus) -> auditory cortex |
|
|
What is the pathway of the startle reflex?
|
Inferior colliculus -> autonomic motor centers
|
|
|
What is the auditory radiation?
|
Thalamus -> temporal gyrus pathway
|
|
|
What are the two primary portions of the vestibular system?
|
Vestibulocochlear nerve + peripheral connections, cerebellum.
|
|
|
Describe the pathway of the vestibular system.
|
Hair cells -> vestibular ganglion (inside internal acoustic meatus) -> vestibulocochlear nerve -> axons terminate on vestibular nuclei (medulla) -> inferior cerebellar peduncle -> cerebellum -> flocculonodular lobe -> the fastigial nucleus of the cerebellum -> bilaterally to vestibular nuclei on ipsilateral and contralateral side of original input (cerebellar-vestibular feedback) -> lateral vestibular nucleus descends ipsilaterally in lateral vestibulospinal tract to synpase on anterior horn cells, superior, medial, and inferior descend ipsilaterally/contralaterally in medial vestibulospinal tract to synpase on anterior horn cells.
|
|
|
What is the receptor organ of the inner ear composed of?
|
Utricle and sacculus (two fluid filled sacs), endolymph, and hair cells.
|
|
|
Describe the vestibulo-ocular tracts
|
Receptor cells in semicircular canals -> impulses to vestibulocochlear nerve -> ganglion fibers synapse on vestibular nuclei -> travel bilaterally in medial longitudinal fasciculus to oculomotor, trochlear, abducens nuclei.
|
|
|
How is the mesencephalic nucleus of V special?
|
*does not involve gussarian ganglion
* only nucleus in the brainstem where you have no synapses in a ganglion *nucleus does not go up the thalamus |
|
|
When dura is compressed, you can get vomiting and nausea. What nerves primarily carry these sensations?
|
Vagus and trigeminal.
|
|
|
What are the 4 causes of true visceral pain?
|
1) Ischemia (lack of blood supply)
2) Chemical stimuli (burns) 3) Spasm of hollow viscus 4) Overdistension of a hollow viscus |
|
|
What are disorders that can cause pain that is thought to be from the TMJ?
|
1) Intracranial lesions (brain tumors of vascular abnormalities)
2) Extracranial lesions (tumors/infections of parotid gland, orbit, ear) 3) Rheumatic or athritic conditions 4) Vascular conditions 5) Myofascial disorders 6) Causalgia 7) Neurogenic conditions (neuritis, neuralgia) 8) Psychogenic problems 9) Cranial arteritis 10) Acoustic neuroma 11) Trigeminal neuralgia |
|
|
What is causalgia?
|
Reflex sympathetic dystrophy - continuous intense pain out of proportion to severity of initial injury
|
|
|
What is an acoustic neuroma? What causes it? What are the symptoms?
|
Radiating pain from mandible, twitching, lack of balance. Facial nerve and vestibulocochlear nerve exit skull through internal acoustic meatus, acoustic neuroma is a slow growing tumor in that area.
|
|
|
What is tic douloureux? What nerves is it associated with?
|
Trigeminal neuralgia - pain in the face that it is horrible. Primarily associated with maxillary and mandibular branches of cranial nerve V
|
|
|
If you have a strong enough force that can blow out the tympanic membrane, why can you lose taste too?
|
Branch of facial nerve that carries taste from the anterior 2/3 of the tongue is called chorda tympani, and it runs with the tympanic membrane. You can blow both of these out and lose both hearing and taste from the anterior 2/3 of the tongue.
|
|
|
If a lady is repeatedly hearing a song when there is no sound around, where could she have a tumor?
|
Superior temporal gyrus - involved with hearing, memory of hearing, perception of hearing, and interpretation.
|
|
|
What two parts of the brain are involved in balance?
|
Brainstem and cerebellum
|
|
|
If you're spinning drunkenly, how do you get nystagmus?
|
You're messing with the vestibular nuclei, which are sending bilateral axons up to the oculomotor, abducens, and trochlear nuclei. Your eyes start spinning left and right.
|
|
|
How do ice skaters not get sick when they spin?
|
They focus on one spot - sends feedback to vestibular nuclei that you're not spinning, overrides barfing mechanism.
|
