Brainstem Flashcards

(86 cards)

1
Q

What sulci do the following nerves exit from?

  1. 12
  2. 11
  3. 10
  4. 9
A
  1. 12: Anterior lateral sulcus
  2. 11: Posterolateral sulcus
  3. 10: Posterolateral sulcus
  4. 9: Posterolateral sulcus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the surface marking which represents the surface marking of the spinal nucleus of the trigeminal nerve?

A

Tuberculum cinereum

BETWEEN THE CUNEATE TUBERCLE AND THE POSTEROLATERAL SULCUS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the structures on the floor of the 4th ventricle?

A

Hypoglossal trigone
Vagal trigone
Facial colliculus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Explain how hemiplegia cruciata works.

A

This happens with injuries to the lower medulla. One side with crossed upper extremity fibers is injured along with uncrossed lower extremity fibers!

Also note that the UE and neck fibers cross first AND ARE MORE SUPERFICIALLY LOCATED.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Which fibers project to nucleus cuenatus and which ones go to nucleus gracilis?

A

C: C1 to T7
G: Below T7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How can one have bilateral upper extremity paresis form a medullary lesion?

A

A lesion that hits the area where both UE fibers decussate.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The spinal trigeminal nuclei

  1. Descends up to what spinal level?
  2. Continuous with what nuclei rostrally and caudally
A

C3

Rostral main sensory nucleus of the trigeminal nerve in the pons

Substantia gelatinosa of the spinal cord

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the 3 divisions of the spinal trigeminal nucleus and what are their functions

A
  1. Caudal nucleus: Pain and temp on the ipsilateral face
  2. Nucleus interpolaris: Dental pain
  3. Nucleus oralis: Tactile sensation from the oral mucosa
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

T or F: The perioral region projects to a more rostral portion of the spinal trigeminal nuclei while the region anterior to the mandible projects to a more inferior division.

A

T

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What nucleus of the thalamus does the trigeminal thalamic tract carrying CN 5, 7, 9, 10 fibers synapse on?

A

VPM

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which fibers in the spinothalamic tract subserve temperature? More dorsal or more ventral?

A

Dorsal fibers

Ventral fibers subserve pain more

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What fibers come from the nucleus gracilis and cuneatus to form the medial lemnisci?

A

Internal arcuate fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the functions of the accessory cuneate nucleus located dorsolaterally to the cuneate nucleus?

A
  1. Unconscious proprioreception: fibers from the dorsal spinocerebellar system
  2. Autonomic functions: Fibers from the vasopressor and cardioaccelaratory areas of the posterior hypothalamus, CN 9 and CN 10
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the area posterma formed from?

A

Astroblast like cells, arterioles, sinusoids and apoloar and unipolar neurons

induces vomiting

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the areas of the brain without BBB?

A
  1. Area posterma
  2. Subcommisural organ
  3. Pineal gland
  4. Subfornical corgan
  5. Organum vasculosum
  6. Neurohypophysis
  7. Median eminence
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 3 peduncles that connect the brainstem and the cerebellum?

A
  1. brachium conjunctivum to midbrain
  2. brachium pontis to pons
  3. restiform body to medulla
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are involved in the Jackson and Tapia syndromes?

A

Jackson: 9 10 11 12 and hemiparesis
Tapia: 9, 10 12

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is also known as Galen’s nerve?

A

Recurrent laryngeal nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Name the CN 10 nuclei and their functions:

A

EFFERENT

  1. Dorsal motor nucleus of Vagus: Preganglionic parasympathetic responsible for
  2. Nucleus ambiguus: ventral motor nucleus of vagus for the muscles of the pharynx and larynx

AFFERENT

  1. Nucleus of the spinal tract of CN 5 receiving somatic afferent fibers from the external ear, external auditory canal, external surface of the tympanic membrane
  2. Nucleus solitarius: Taste from the epiglottis (rostral) and general visceral (caudal) afferent from the pharynx and larynx, trachea and esophagus– also receives taste from 7 and 9
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Name the CN 9 nuclei and their functions:

A
  1. Nucleus ambiguus: motor to the stylopharyngeus msucle
  2. Inferior salivatory nucleus for the parotid gland
  3. Nucleus of the spinal tract of CN 5 for the retroauricular region
  4. Nucleus solitarius: taste from the posterior 1/3 of the tongue and general visceral afferent from the posterior 1/3 of tongue and tonsils and eustachian tube
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How does the CN9 contribute to the regulation of BP and HR?

A

Receives the carotid sinus nerve which innervates the carotid body (chemoreceptor) and carotid sinus (baroreceptor)– based on these inputs it can send volleys of signals to the dorsal vagal nucleus to effect HR and BP changes.

Nucleus is solitarius

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Which vestibular nuclei are in the medulla?

A

Medical and inferior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Where do taste fibers synapse at the thalamus?

A

Ventroposteromedial

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Lesions where cause Ondine’s curse?

A

Failure of automatic respiratory function asleep

Nucleus ambiguus and the adjacent reticular formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Where are the inspiratory and expiratory neurons?
Inspiratory neurons are driven by nucleus solitarius | N ambiguus and n retroambiguus contains both
26
What is the effector site for neurogenic pulmonary edema?
N. Solitarius
27
Where are the dorsal swallowing group and dorsal respiratory group ventral SG and ventral RG Located?
Dorsal N ambiguus Ventral N solitarius
28
What are the inputs to the vomiting center in the nucleus solitarius?
Area postrema Tast: CN 7, 9, 10 Autonomics Vestibular system
29
What NT is secreted by: 1. CN 12 nucleus 2. Dorsal motor nucleus of vagus 3. Nucleus ambiguus 4. Reticular formation 5. Raphe nucleus
1. CN 12 nucleus Ach 2. Dorsal motor nucleus of vagus Ach 3. Nucleus ambiguus Ach 4. Reticular formation: NE, Enkephalin 5. Raphe nucleus Serotonin, Enkephalin
30
What are the sxs of 1. Dejerine anterior bulbar syndrome/ Medial medullary syndrome 2. Wallenburg
1. Ipsilateral 12, contalateral hemiparesis with sparing of the face, contralateral loss of position sense 2. Contralateral loss of pain and temp on the body but ipsilateral on the face Ipsilateral horner's syndrome N ambiguus: dysphagia and dysarthria Vestibular nuc: Dizziness, vomiting Inferior cerebellar peduncle: ataxia Hiccups Olivoverebellar fibers: Ocular lateropulsion saccadic eye movements with hypermetria toward the side of the lesion and hypometria away from it
31
What areas are affected with the babinski nageotte syndrome?
Combined lateral and medial medullary syndrome
32
What are affected: 1. Vernet 2. Collet Sicard 3. Villaret
1. Vernet: 9 10 11 2. Collet Sicard: 9 10 11 12 3. Villaret: 9 10 11 12 sympathetic
33
What is the largest group of fibers in the basis pontis?
The corticopontocerebellar fibers responsible for rapid correction of movements
34
What percentage of the tegementum needs to be lost before loss of consciousness occurs?
25%
35
Going from medial to lateral what is the arrangement of the sensory lemniscal system?
Medial L Spinal L Trigeminal L Lateral L for hearing
36
What NT is released from the locus coeruleus? Where is it found? Roles?
Norepinephrine Generalized cell loss in PD Rostral part loss in AD Location: Rostral pons and caudal midbrain Roles: Regulation of respiration and REM sleep
37
Dorsal cochlear nucleus? or ventral? Fibers from the basal turns of cochlea for high frequency sounds Fibers from the apical turns for low frequency sounds
Dorsal Ventral
38
Re: Auditory pathway: The ventral acoustic striae is also known as? Where does it project? Which striae is the largest?
Trapezoid body Projects to the superior olivary complex-- functions to detect interaural sound intensity and provide feedback control of cochlear mechanism and process cochlear signals via the ascending auditory pathway Ventral is largest
39
From the lateral lemnisci where do auditory fibers go? Identify the 4 decussations.
Inferior colliculi, Medial geniculate body, Transverse Heschl's gyri B41 and 42 1. Pontine tegmentum acoustic striae 2. Olivocochlear bundle efferent bundle of rasmussen in the pontine tegmentum as well-- protective against loud sound! 3. Nuclei of the lateral lemniscus-- connected by Probst's commissure passing through the bachium conjunctivum 4. Midbrain level between two IC
40
What is the Olivocochlear bundle for?
Feedback inhibition to the organ of Corti-- protective against loud sound and for selective auditory attention
41
Match the following: 1. Deiter's Nucleus 2. Schwalbe's nucleus 3. Spinal nucleus 4. Bechterew's nucleus Superior Inferior Lateral Medial
1. Deiter's Nucleus Lateral 2. Schwalbe's nucleus Medial 3. Spinal nucleus Inferior 4. Bechterew's nucleus Superior
42
Match the following: 1. Deiter's Nucleus 2. Schwalbe's nucleus 3. Spinal nucleus 4. Bechterew's nucleus Flexor motor neurons Extensor motor neurons Connects with doral motor nucleus of the vagus to effect autonomic functions associated with vestibular stimulation
Flexor motor neurons Schwalbe Extensor motor neurons Deiter Connects with doral motor nucleus of the vagus to effect autonomic functions associated with vestibular stimulation Schwalbe
43
Placing warm water in the right ear will result in what kind of nystagmus.
Slow to the left Fast to the right COWS Warm Same (After fast component) Crawling away from the heat!
44
In INO why is there nystagmus in the contralateral eye?
Convergence mechanism-- driving the contralateral eye to be in the same position as the ipsilateral eye to avoid diplopia Without the MLF there is no inhibition of adduction of the contralateral eye
45
What are the 2 types of fibers carried by CN 7? What are the primary ganglia of both? What cranial nuclei do they go to?
External ear sensation goes to the spinal trigeminal ganglion and taste from anterior 2/3 of the tongue goes to the gustatory part of nucleus solitarius Geniculate ganglion
46
The peripheral lateral root of the facial nerve subserving taste is called the?
Nervus intermedius or the Wrisberg's nerve-- MORE PROXIMAL to chorda tympani nerve
47
What explains the central facial palsy in those with pontine tegmenutm and medullary infarcts?
There is an aberrant bundle headed for the CN7 nuclei that separates from the corticobulbar fibers in the caudal basis pontis, heads to the facial nucleus in the tegmentum but forms a loop down into the medulla oblongata before reaching the facial colliculus
48
What glands are innervated by CN 7?
Greater superficial petrosal nerve >> Pterygopalatine ganglion >> Lacrimal gland Chorda tympani and lingual nerves >> submandibular ganglion >> Submandibular gland and sublingual gland
49
Besides the facial muscles what other muscles are innervated by CN 7? What muscles are innervated by CN 5 besides muscles of mastication?
7: Stapedius Stylohyoid Posterior belly of the digastric 5: Tensory tympani Tensor palati Mylohyoid ANTERIOR belly of the digastric
50
Distal to the geniculate gagnlion what CN7 function would still be intact if transection were to occur?
Lacrimation
51
What are the two connections of the PPRF?
Caudal to the abducens nucleus for ipsilateral gaze Rostral to the rostral interstitial nucleus of the MLF
52
Identify which nuclei of cranial nerve 5 subserve these sensations? 1. Mechanisms that control the force of the bite 2. Proprioreceptive inputs: pressue and kinesthesia from teeth, mastication stretch receptors etc 3. oral mucosa tactile sensibility 4. dental pain 5. paint and temp sensation of the face 6. discriminative touch
1. Mechanisms that control the force of the bite: Mesencephalic 2. Proprioreceptive inputs: pressue and kinesthesia from teeth, mastication stretch receptors etc: Mesencephalic 3. oral mucosa tactile sensibility: Spinal rostral 4. dental pain: Spinal interpolaris 5. paint and temp sensation of the face: Spinal caudalis 6. discriminative touch: Main sensory
53
The internal auditory artery that arises from the AICA or the basilar a supplies what? Which part of the pons is supplies by the AICA?
Auditory, vestibular and facial nerves Lateral part of the lower 2/3-- the upper pons is mostly basilar artery with a little SCA
54
What are the basal pontine syndromes: 1. Ipsilateral facial paralysis, ipsilateral abduction paralysis, contralateral hemiparesis 2. Variable Ipsilateral facial, unilateral deafness, contralateral hemiparesis 3. Ipsilateral facial spasm with contralateral hemiparesis
1. Ipsilateral facial paralysis, ipsilateral abduction paralysis, contralateral hemiparesis: Millard gubler 2. Variable Ipsilateral facial, unilateral deafness, contralateral hemiparesis: Gelle syndrome 3. Ipsilateral facial spasm with contralateral hemiparesis: Brissaud-sicard syndrome
55
What is type 2 INO?
cavernous sinus thrombosis-- CN6 with ICA involvement
56
What are the tegemental pontine syndromes: 1. Ipsilateral facial paralysis, Gaze palsy, Contralateral paralysis 2. ipsilateral INO, contralateral hemisensory loss, ipsilateral ataxia
1. Ipsilateral facial paralysis, Gaze palsy, Contralateral paralysis: Foville syndrome 2. ipsilateral INO, contralateral hemisensory loss, ipsilateral ataxia: Raymond-cestan-chenais
57
Ocular bobbing are seen in what brainstem lesions?
Pontine
58
What are the components of the basis pedunculi of the midbrain?
Substantia nigra and the cerebreal peduncles
59
What are the 3 nuclei of the inferior colliculus?
1. Central nucleus: major relay nucleus 2. Pericentral nucleus for directing to auditory attention 3. External nucleus: Acousticomotor reflexes
60
Re: Midbrain Connections of the IC and SC serves to?
Turn neck and eyes in response to sound
61
What part of the midbrain is the brachium conjunctivum located in? How about the red nucleus?
The inferior colliculus level Superior colliculus They both occupy the central tegmentum
62
A trochlear lesion will result in a head tilt going towards the?
Tilt away from the side with the lesion Diplopia is worse looking contralaterally and downward
63
What NT is secreted by the dorsal raphe nuclei in the midbrain?
Serotonin
64
Starting from the lateral portion, what composes the cerebral peduncle?
Parieto-occipito-temporo pontine projections Corticospinal and corticobulbar Frontopontine fibers
65
What 2 disease entities have loss of both the pigmented and non-pigmented neurons of the SN?
Huntington disease and PD dementia In PD there is a central loss pattern of pigmented neurons ONLY!
66
What are the parts of the Substantia nigra and their contents?
Pars compacta: Melanin | Pars reticulata: Iron
67
What are the three divisions of the mesencephalic dopaminergic system?
Mesostriatal: Putamen, caudat, GP (PD with hypoactivity and HD hyperactivity) Mesoallocortica/limbic: Amygdala, olfactory tubercle (Cognition with hypoactivity, Pyschosis with hyperactivity) Mesoneocortical: Frontal, temporal, parietal and occipital cortices (Cognition, photosensitive epilepsy if with hypoactivity)
68
What are the components of the Sylvian aqueduct syndrome AKA Koerber Salus Elschnig syndrome?
Parinaud 1. Vertical gaze palsy 2. Anisocoria/ Light near dissociation 3. Conversion retraction nystagmus 4. Lid retraction (Collier's sign) 5. Imparied convegence
69
What part of the brainstem does the lateral lemniscus terrminate in?
Caudal midbrain at the IC!
70
Palatal myoclonus occurs with a lesion in?
Mollaret triangle: Red nucleus in the midbrain, Dentate nucleus in the cerebellum OF THE OPPOSITE SIDE, Inferior olive in the medulla
71
Rubrospinal tract facilitates what motor neurons?
Facilitates flexor motor neurons and inhibits extensor motor neurons
72
A lesion of the red nucleus of the MB results in tremor where?
Contralateral side
73
What projects to the CN3 nuclei for 1. Upward gaze 2. Downward gaze 3. Pupilloconstriction
1. Upward gaze: Interstitial nucleus of Cajal 2. Downward gaze: RiMLF BUT IF BILATERAL DAMAGE TO RIMLF BOTH UPWARD AND DOWNWARD GAZE ARE AFFECTED! Also-- Cajal lesions also result in ABOLITION OF THE OCULOCEPHALIC RESPONSE 1 and 2 project to the motor cell column (compare with #3 below) 3. Pupilloconstriction: Pretectal olivary nucleus-- projects to the visceral cell column where Edinger Westphal nucleus is
74
What are the only nuclei of CN3 that are unpaired?
Levator and Edinger Westphal
75
What are the components of CN3 after they bifurcate anterior to the cavernous sinus?
Superior: Levator and Superior rectus Inferior: Medial rectus, inferior oblique, iris sphincter
76
Injury of what nucleus in the midbrain results in bilateral eyelid retraction?
Nuclei of the posterior commissure
77
What is an extension of the hypothalamus in the midbrain and serves to connect it with the periaqueductal gray matter and the autonomic nuceli in the pons and medulla?
Dorsal longitudinal fasciculus | Contains autonomic fibers
78
What are the roles of the periaqueductal gray matter in the midbrain?
Modulate analgesic mechanisms-- and essentially all autonomic functions! Escape behaviour, micturition, erection
79
What are the effector muscles of the light reflex?
Sphincter pupillae and ciliaris muscle
80
What is an Adie's pupil?
Widely dilated pupil with a sluggish, prolonged pupillary contraction in reaction to light-- when constricted takes along time to dilate as well! Pathology is within the ciliary ganglion!
81
What are the 3 components of the accommodation reflex?
Convex lens Contraction of both medial recti Pupillary constriction
82
Describe the argyll robertson pupil.
Constricts to accommodation but not to light
83
Describe the posterior pathway for saccadic movements
Originates in the pariteo occipital cortex unto the SC then to the brainstem centers for REFLEX SACCADIC MOVEMENTS VS anterior pathway from FEF
84
What is the main midbrain blood supply especially at the superior colliculus level?
PCA
85
Describe the midbrain syndromes 1. Weber 2. Claude 3. Benedict 4. Nothnagel 5. Plus minus lid syndrome 6. Walleyed syndrome
1. Weber: Basis-- Ipsilateral CN3, contralateral hemiparesis 2. Claude: Tegmentum-- Ipsilateral CN3, contralateral tremor 3. Benedict: Basis with tegmentum: Combined! 4. Nothnagel: Tectum/ quadrigeminal plate-- Bilateral asymmetric CN3 palsy, contralateral or ipsilateral ataxia, vertical gaze palsy! 5. Plus minus lid syndrome: Posterior commissure-- Ptosis in one and retraction in the other 6. Walleyed syndrome: Bilateral INO-- exotropic eyes looking outwards UNABLE TO ADDUCT BILATERALLY! TREMOR IS RUBRAL TREMOR: Rest tremor from involvement of the SN while there is also a kinetic tremor from the red nucleus and cerebellar peduncle involvement
86
What is seen in peduncular hallucinosis?
Animals! And people-- allegedly from midbrain tegmentum damage