Lab Section 6 Flashcards Preview

Neuro > Lab Section 6 > Flashcards

Flashcards in Lab Section 6 Deck (46):

where do axons in the basis of the pons go?

to the middle cerebellar peduncle


which cranial nerves can be seen on the pons?

CN 5- CN 8
although 8 is typically considered as part of the medulla


where can CN 7-5 be located?

7: just medial to the vestibulocochlear nerve at the pontine medullary junction
6: in the PM junction medially
5: piercing the middle cerebellar peduncle in the middle of the pons


what does the superior cerebellar peduncle carry?

axons from the deep cerebellar nuclei to the brainstem and the forebrain


what lies deep to the two vestibular areas? what are they located inferior to?

the vestibular nuclei
inferior to the facial colliculi


what is deep to the facial colliculus?

the abducens nucleus and motor axons from the facial nucleus that loop over the abducens nucleus prior to exiting


what are the three markers of transition from the medulla to the pons?

pyramids disappear and are replaced by the striated basis of the pons
vestibular nuclei
blending of ICP with the white matter of the cerebellum


what structures appear at all levels of the pons?

middle cerebellar peduncle, pontine nuclei, superior cerebellar peduncle and the pontine reticular formation


what is the genu of the facial nerve?

the portion that curves around the abducens nucleus


where does the spinal nucleus of CN 5 extend to?

the level of the facial colliculus


what do the raphe nuclei neurons secrete use as neurotransmitters and what do they modulate?

modulate responses of the hypothalamic and cerebral neurons


what are noradrenergic neurons within the pons involved with? name one group of these neurons.

autonomic reflexes and pain sensation
Locus Ceruleus


where do the auditory fibers travel through and cross in, post cochlear nuclei?

the trapezoid body (around the area of the medial lemniscus)


where do many of the axons of the trapezoid body terminate? where do they go after that?

in the superior olive
lateral lemniscus


where does the lateral lemniscus terminate?

in the inferior colliculus


what component of CN 5 controls the jaw? which portion processes epicritic information? which portion processes proprioceptive information?

motor nucleus of 5
Principal sensory nucleus of 5 and pontine portion of the spinal nucleus of 5
mesencephalic nucleus of 5


where do axons from the mesencephalic tract of 5 go?

they synapse with the motor nucleus of 5 > reticular formation > cerebellum


where doe sthe medial lemniscus shift in the pons?

shifts further laterally and dorsally while moving more rostrally in the pons and midbrain


what information synapses in the periaqueductal gray matter of the midbrain?

pain and temperature information from the anterolateral system


what does the medial longitudinal fasciculus connect?

the superior colliculus, vestibular nuclei, cranial nerve nuclei 3,4 and 6, and the cervical spinal cord


what does desctruction of the MLF in the pons cause?

horizontal nystagmus and loss of conjugate horizontal eye movements (internuclear opthalmoplegia)


what is normal when the MLF is damaged?

convergence of the two eyes


what does the PPRF do?

coordinates conjugate horizontal eye movements


what are the three predominant outputs for the vestibular nuclei?

the cranial nerve nuclei that move the eyes (MLF)
spinal cord to maintain posture
cerebellum (ICP)- balance and reflexive eye movements


what are the symptoms of vestibular nuclei damage?

nystagmus, balance loss, vertigo and nauseousness


in what way can pathology of CN VII lead to eye damage?

inability to close the eye and loss of PNS control of the lacrimal glands


describe the mechanism of the corneal reflex.

CN V receives noxious input from the irritation to the cornea and CN VII closes the eye


which nerve or nucleus would be damaged with internal strabismus?

abducens nucleus (CN VI)


where do most axons from the spinal nucleus of V terminate?

in the reticular formation


what does epicritic information from the CN V nucleus travel with?

epicritic sensation from the rest of the body in the medial lemniscus


what are the origins and terminations of axons in the inferior cerebellar peduncle? what kind of information does it include?

spinal cord and medulla > cerebellum
proprioceptive information from the body mostly


what three tracts input to the cerebellum via the ICP?

spinocerebellar tracts
inferior olivary complex
vestibular nucleus


from where does the inferior olive receive input?

from the cerebral cortex, the red nucleus and from the spinal cord


what are the origins and terminations of axons in the middle cerebellar peduncle?

carries info from the pons (pontine nuclei) to the cerebellum


what are the origins and terminations of axons in the superior cerebellar peduncle?

carries info from the deep cerebellar nuclei to the tegmentum of the pons right below the inferior colliculus


what happens to the axons immediately after they leave the superior cerebellar peduncle?

they decussate at the decussation of the superior cerebellar peduncle


what are the targets of axons from the superior cerebellar peduncle?

areas of pontine reticular formation
red nucleus
VA and VL nuclei


what are the four deep cerebellar nuclei?

the fastigial, globose, embolliform and dentate nuclei


where do the deep cerebellar nuclei receive most of their input from?

the cerebellar cortex


where do the medial pair of deep cerebellar nuclei receive most of their input from?

from axial related structures like the vestibular nuclei and reticular formation


where do the lateral pair of deep cerebellar nuclei receive most of their input from?

related to distal limb control


midline pathology of the cerebellum affects which muscles? lateral pathology?

axial muscles-affect balance
limb movement


what is ataxia?

difficulty in making coordinated movements not attributable to paralysis


disturbance of balance is a symptom of damage of what cerebellar structures?

vermis or flocculus


T or F: hypotonia is not a common symptom of cerebellar damage.



which three symptoms may result from either vestibular or cerebellar pathology?

disturbance in posture, disturbance in balance and nystagmus