Chapter 23 The Vestibular Nuclei Flashcards
The vestibulocochlear nerve has a ____________ division concerned with hearing and a _________________ division concerned with balance.
cochlear
vestibular
The _____________ and _________ divisions of the vestibulocochlear nerve join inside the petrous part of the temporal bone and emerge from the temporal bone into the posterior cranial fossa through the internal acoustic meatus.
vestibular
cochlear
Immediately after leaving the temporal bone through the ___________ _________ _________ the vestibulocochlear nerve passes through the dura and distributes its fibers to the ________________ and _________ nuclei.
internal acoustic meatus
vestibular
cochlear
The vestibular division of the ______________________ ________is composed of the axons of neurons in the ________________ ganglion.
vestibularchochlear nerve
vestibular
Four vestibular nuclei and the nodulus of the cerebellum receive projections from the _________________ ganglion.
vestibular
The ____________ ___________ ___________ in the vestibular ganglion receive impulses from the hair cells of the 3 semicircular canals and the saccule and the utricle.
primary sensory neurons
The axons of neurons in the vestibular ganglion synapse on neurons in the nodulus of the _______________ and in the _______________ __________.
cerebellum
vestibular nuclei
There are ___ vestibular nuclei in the dorsolateral quadrant of each side of the brainstem.
4
The 4 vestibular nuclei form a kite shaped group that straddles the
ponto-medullary boundary
The lateral and superior vestibular nuclei are mostly in the _______, and the medial and inferior vestibular ganglia are mostly in the _____________.
pons
medulla
The superior vestibular nucleus is in the ___
pons
The lateral vestibular nucleus is in the pons lateral to the ____________ ________________ _________.
superior vestibular nucleus
The lateral vestibular nucleus is ___________ to the superior vestibular nucleus in the ________.
lateral
pons
The medial vestibular nucleus is ___________ to the _______________ ___________________ __________ in the ______________.
medial
inferior vestibular nucleus
medulla
The pons is _____________ to the medulla in humans.
superior
Since the right and left _________ _______________ _________ are much closer to each other than the right and left inferior vestibular nuclei are, there is much more communication between the _________ ______________ _________ than between the right and left inferior vestibular nuclei.
medial vestibular nuclei
medial vestibular nuclei
Since the right and left _____________ ______________ _________ are somewhat closer together than the right and left lateral vestibular nuclei are, there is much more communication between the _________ ______________ _________ than between the right and left lateral vestibular nuclei
superior vestibular nuclei
superior vestibular nuclei
There is much communication between the right and left _________ ________________ __________ and between the right and left ______________ _______________ __________, but little communication between the right and left ____________ _______________ ________ and the right and left __________ ________________ _________.
medial vestibular nuclei
superior vestibular nuclei
inferior vestibular nuclei
lateral vestibular nuclei
The inferior and medial vestibular nuclei are in the upper ____________ medial to the inferior cerebellar peduncle.
medulla
The medial vestibular nucleus forms most of the medial border of the _____________ _________________ ______________.
inferior vestibular nucleus
The inferior vestibular nucleus forms the lateral border of the ___________ ___________________ __________ and the _______________ ___________.
medial vestibular nucleus
nucleus solitarius
The medial vestibular nucleus forms the dorsal border of the ______________ _________ and the _____________ _______________ __________.
nucleus solitarius
inferior salivatory nucleus
The lateral and dorsal borders of the nucleus solitarius are formed by the ____________ and ________ _____________ _________.
inferior
medial vestibular nuclei
The nucleus solitarius receives projections from the __________ and __________ _______________ __________, which form its lateral and dorsal borders.
medial
inferior vestibular nuclei
The medullary part of the nucleus solitarius receives inputs from the ________ and ___________ _______________ ________ about changes in posture detected by the vestibular organs.
medial inferior
vestibular nuclei
Projections of the nucleus solitarius to the __________ _______________ allow the _________ ______________ to increase or decrease cardiac output to maintain consciousness during postural changes.
nucleus ambiguus
nucleus ambiguus
The nucleus solitarius integrates blood pressure information from the ____________ ______________________ __________ with postural information from the __________ and _____________ _______________ _________ to regulate cardiac output.
superior glossopharyngeal ganglion
medial
inferior vestibular nuclei
Projections from the nucleus solitarius regulate the output of the __________ ______________ to the cardiac ganglion in the sinus node of the heart.
nucleus ambiguus
The regulation of blood pressure during changes in posture depend on projections from the ________ and _________ ______________ nuclei to the nucleus _______________ and from the nucleus _______________ to the nucleus _____________.
medial inferior vestibular solitarius solitarius ambiguus
The medial vestibular nucleus also receives from neurons in the ______________ __________ that innervate the lateral (or horizontal) semicircular canal.
vestibular ganglion
The medial vestibular nucleus receives information about rotation in the ______________ plane.
horizontal
Because the semicircular canals are nearly circular, they respond to _____________ but not to linear movement.
rotational
When the head turns, the eyes _______ in the opposite direction because the ________ _______________ nucleus relays information about horizontal rotation to the abducens nucleus which controls lateral eye movement.
turn
medial vestibular
Turning of the eyes in response to ____________ of the ________ is called nystagmus.
rotation (or turning) head
Horizontal nystagmus depends on responses of the hair cells of the _____________ ________________ _______, neurons in the vestibular ganglion, ________ _______________ ________, and abducens nucleus, in that order
horizontal semicircular canal
medial vestibular nucleus
The medial vestibular nucleus mediates horizontal _______________.
nystagmus
The eyes return quickly after they have ____________ as far as they can in nystagmus.
turned
The return phase is called the beat of ________________.
nystagmus
When the head turns to the left, the eyes turn to the _________ as far as they can and then beat back to the ________.
right
left
A pirouette to the right causes _____________ that beats to the _________.
nystagmus right
Projections of the medial vestibular nucleus to the abducens nucleus mediate ______________ _______________.
horizontal
nystagmus
Vertical ________________ occurs when the head turns up or down in the sagittal plane.
nystagmus
Hair cells in the anterior and posterior semicircular canals respond to ___________ of the head in any vertical plane because the anterior and posterior semicircular canals are in ____________planes 90o apart.
turning
vertical
Neurons in the ________________ ganglion send most of the information from the anterior and posterior semicircular canals to the superior vestibular nucleus in the ________.
vestibular
pons
Vertical nystagmus is due to the response of the ____________ _______________ _________ to information from the ____________ and _____________ _________________canals.
superior vestibular nucleus
anterior
posterior
Vertical nystagmus requires projections from the ____________ _______________ __________ to the oculomotor nucleus which contains the lower motor neurons for the muscles that control vertical movements of the eyes.
superior vestibular nucleus
The projections of the ____________ _______________ __________ to the oculomotor nucleus travel in the ipsilateral medial longitudinal fasciculus.
superior vestibular nucleus
The projections of the ____________ _______________ __________ to the oculomotor nucleus travel in the ipsilateral medial longitudinal fasciculus.
superior vestibular nucleus
The oculomotor nucleus receives inputs from the superior vestibular nucleus through the ____________ ________ _____________ _______________.
ipsilateral medial longitudinal fasciculus
The superior vestibular nucleus projects to the ipsilateral _________________ nucleus and the ipsilateral thalamus.
oculomotor
The superior vestibular nucleus communicates with the ipsilateral oculomotor nucleus via the __________ ______________ _________________ and with the ipsilateral thalamus via the medial lemniscus.
medial longitudinal fasciculus
The ___________ _______________ __________ is a major source of inputs to the oculomotor nucleus.
medial longitudinal fasciculus
Vertical nystagmus depends on projections of the _____________ __________________ nucleus in the pons to the oculomotor nucleus in the midbrain.
superior vestibular
Horizontal nystagmus depends on projections of the __________ _______________ nucleus to the abducens nucleus in the pons
medial vestibular
The medial vestibular nucleus mediates _____________ ___________, and the superior vestibular nucleus mediates ___________ _____________ in response to movements of the head.
horizontal nystagmus
vertical nystagmus
Nystagmus beats in the __________ direction as the turn of the head.
same
The superior vestibular nucleus projects to the ______________ thalamus, but the medial vestibular nucleus projects to the contralateral thalamus.
ipsilateral
The medial vestibular nucleus projects to the contralateral ____________ via the medial longitudinal fasciculus.
thalamus
The thalamus receives projections from the _______________ medial vestibular nucleus via the medial longitudinal fasciculus.
contralateral
The thalamus receives projections from the _______________ superior vestibular nucleus via the __________ ______________ and projections from the ______________ medial vestibular nucleus via the _________ _______________ _________________.
ipsilateral medial lemniscus
contralateral medial longitudinal fasciculus
All vestibular nuclei project to the nodulus of the _______________.
cerebellum
The medial and inferior vestibular nuclei adjust blood pressure for postural changes through their projections to the ___________ ________________.
nucleus solitarius
The medial vestibulospinal tracts are mostly axons of neurons in the _________ ________________ _________.
medial vestibular nuclei
Each medial vestibular nucleus contributes axons to both the _________ and the ___________ ___________________ _________.
medial
lateral
vestibulospinal tract
The medial vestibulospinal tracts run down through the right and left sides of the ____________ funiculus of the __________ _________ posterior to the _________________ ________.
anterior
spinal cord
anterior corticospinal tracts
The medial vestibulospinal tracts run down through the right and left sides of the ____________ funiculus of the __________ _________ posterior to the _________________ ________.
anterior
spinal cord
anterior corticospinal tracts
The medial vestibulospinal tracts are confined to the ____________ levels of the __________ _______.
cervical
spinal cord
The axons in each medial vestibulospinal tract synapse on internuncial neurons that synapse on lower motor neurons for _______ _____________.
neck muscles
Axons in the tectospinal tract also synapse on internuncial neurons that synapse on lower motor neurons for _______ ____________.
neck muscles
The _______________ tract is responsible for tracking movements of the head, but the ____________________________ tract is responsible for balancing movements of the head.
tectospinal
medial vestibulospinal
Each medial vestibular nucleus receives information from all ____ semicircular canals and from the saccule and utricle.
3
Each medial vestibular nucleus generates reflexes that stabilize the ________ via ________ medial vestibulospinal tracts.
head
both
The tectospinal tracts are responsible for reflexive _____________ movements of the head, and the medial vestibulospinal tracts are responsible for _______________ movements of the head.
tracking
balancing
Each lateral vestibular nucleus contributes axons to the _______________ lateral vestibulospinal tract.
ipsilateral
The lateral vestibulospinal tract is the most anterior tract in the _____________ funiculus of the _________ __________.
anterior
spinal cord
Axons in the lateral vestibulospinal tract synapse on _______________ neurons that synapse on lower motor neurons for ______________ muscles in the _______________ horn of the spinal cord.
internuncial
extensor
anterior
The righting reflex mediated by the ___________ _______________ __________ tries to keep the sagittal plane of the body aligned with the force of gravity.
lateral vestibulospinal tract
The ____________ reflex depends on input from the macula of the saccule to the lateral vestibular nucleus and on input from the lateral vestibular nucleus to the anterior horn of the spinal cord.
righting
The principal input to the lateral vestibular nucleus is from neurons in the _________________ ____________that innervate the ___________ of the _____________.
vestibular ganglion
macula of the saccule
The medial vestibular nucleus projects to internuncial neurons in the anterior horns of the ___________ spinal cord through _________ medial vestibulospinal _________.
cervical
both
tracts
The _________ ______________ __________ projects to the contralateral thalamus via the contralateral __________ _____________ ______________.
medial vestibular nucleus
medial longitudinal fasciculus
The ___________ ______________ __________ projects to the ipsilateral thalamus via the ipsilateral __________ ______________.
superior vestibular nucleus
medial lemniscus
The inferior vestibular nucleus is entirely in the ___________.
medulla
The medial vestibular nucleus is mostly in the ___________.
medulla
. The lateral vestibular nucleus is mostly in the _______.
pons
The superior vestibular nucleus is entirely in the ______.
pons
Projections of the medial and inferior vestibular nuclei to the ___________ __________________ mediate the response of __________ _____________ to postural changes.
nucleus solitarius
blood pressure