Section 5, Part 3 Flashcards Preview

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Flashcards in Section 5, Part 3 Deck (34)
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1
Q

What terminates in the gracile nucleus?

A

Dorsal column axons of the gracile fasciculus

2
Q

What are arcuate fibers?

A

They are axons of the gracile and cuneate nuclei neurons that cross the midline and carry somatosensory and proprioceptive information from the upper and lower half of the body

3
Q

Do arcuate fibers cross to the opposite side?

A

Yes they decussate

4
Q

After arcuate fibers cross the midline, what are they renamed?

A

Medial Lemniscus

5
Q

Do fibers ascend the medial lemniscus in a somatotopic fashion?

A

Yes they do

6
Q

If you were to lesion the medial lemniscus…what would the symptoms be?

A

Epicritic deficits on the opposite side of the body

7
Q

WHen does somatosensory information from the face join the medial lemniscus?

A

The pons

8
Q

If you were to lesion the anterolateral tract in the medulla….what would the symptoms be?

A

loss of pain and temperature on the opposite side of teh body

9
Q

When the anterolateral tract in the medulla is lesioned, what other structure is usually affected as well?

A

Spinal tract of nucleus V….so you get pain and temp loos on the same side of the head

AND

Vestibular area/ inferior cerebellar peduncle…so there are sometimes cerebellar and vestibular symptoms

10
Q

what is the function of the inferior cerebellar peduncle?

A

Major cerebellar related pathway in the medulla that carries mainly afferent information to the cerebellum from several locations

11
Q

What is the accessory cuneate nucleus?

A

A pateral protrusion of the cuneate nucleus that receives cuneate fasciculus axons carrying proprioceptive information from the upper half of the body

12
Q

Where can the inferior olivary nucleus/ complex be found?

A

The ventrolateral portion of the open medulla and the rostral part of the closed medulla

13
Q

What is the function of the inferior olivary nucleus?

A

It is a cerebellar relay

14
Q

Where does the input of the inferior olivary nucleus come from?

A

The red nucleus, spinal cord and cerebral cortex

15
Q

Where does the inferior olivary nucleus send axons to?

A

It sends axons to the inferior cerebellar peduncle

16
Q

What are the symptoms of an inferior cerebellar peduncle lesion?

A

ataxia and intention tremor on the ipsilateral side of the body

Ex- patients lean to the side of the lesion and have clumsiness and a tremor when using the ipsilateral hand

17
Q

What artery supplies the inferior cerebellar peduncle?

A

PICA

18
Q

Where do the fibers of CN XII emerge from on the brainstem?

A

exit between the olive and the pyramid

19
Q

If you were to lesion the left CN XII, what side would the tongue deviate to?

A

It would deviate to the left (damage is ipsilateral) i the lesion is to the nerve or the nucleus

If the lesion is in the cortex or anywhere rostral to the medulla it would deviate to the right (conralateral)

20
Q

What is the nucleus ambiguous?

A

A long thin column of motor neurons that occur at most levels of the medulla

21
Q

What do the axons of the nucleus ambiguous control?

A

They mainly project CN 9 and CN 10 to innervate the larynx and the pharynx

22
Q

If there is a (unilateral) lesion to the nucleus ambiguous, what are the symptoms?

A

Hoarsness, impaired swallowing and asymmetry of the soft palate

23
Q

What is the dorsal nucleus of the vagus made of?

A

Preganglionic parasympathetic neurons of teh vagus nerve

They terminate in the ganglia related to cardiac muscle and smooth muscle

24
Q

What does the solitary nucleus recieve?

A

It receives afferent information from the pharynx and larynx and from the cardiovascular system and the GI system via cranial nerves 7, 9 and 10

25
Q

What is the vestibular area?

A

It is an area that recieves vestibular information from CN 8 and has different projections to other nuclei for vestibular reflexes and to the cerebellum via the inferior cerebellar peduncle

26
Q

Where are the dorsal and ventral cochlear nuclei found?

A

At the transition between the pons and medulla on the external surface of the inferior cerebellar peduncle

27
Q

What is the function of the cochlear nuclei?

A

They recieve primary afferent input from the auditory portion of the CN 8 (the origin of the auditory pathway

28
Q

If there is damage to the left cochlear nuclei….what symptoms are found?

A

Deafness of the ipsilateral ear

29
Q

Damage to the vestibular nuclei results in what symptoms?

A

Nystagmus, vertigo ad problems with balance

30
Q

What are the symptoms of a CN VIII lesion?

A

Deafness in ipsilateral ear, nystagmus, vertigo, problems with balance

31
Q

What are the symptoms of a CN IX lesion?

A

Loss of gag reflex on the side of the oropharynx of the nerve injury (afferent loss to the solitary nucleus)

32
Q

What are the symptoms of a CN X lesion?

A

Hoarseness due to loss of control of the larynx and difficulty swallowing, asymmetry of the soft palate

bilateral involvement can lead to chocking

33
Q

What are the symptoms of a CN XI lesion?

A

inability to elevate the ipsilateral shoulder, difficulty to turn and tilt head, fasciculations and atrophy of the sternocleidomastoid and trapezius muscles

34
Q

What are the symptoms of a CN XII lesion?

A

Paralysis of the ipsilateral tongue muscles, deviation towards the side of the weakness upon protrusion, atrophy, fasciculations of tongue muscles ipsilaterally