Brainstem-Gilland Flashcards

1
Q

What does the brainstem consist of?

A

midbrain, pons, and medulla

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2
Q

The midbrain tectum is comprised of what?

A
  • quadrigemminal bodies AKA superior and inferior colliculi

- the tectum forms the ROOF of the the MIDBRAIN

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3
Q

Where is the basal portion of the pons located?

A

ventral side

  • basilar part of pons is the ventral part of the pons
  • the dorsal part is known as the pontine tegmentum
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4
Q

The tegmentum is located in what areas of the brainstem?

A

it is located beneath the ventricles

midbrain and pons
-extends from the substantia nigra to the cerebral aqueduct

-forms the floor of the midbrain (mesencephalon)

The tegmentum (core) of the brainstem includes the cranial nerve nuclei, ascending sensory pathways, reticular formation, and periaqueductal gray matter and is involved in a variety of functions.

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5
Q

Anterior/Superior medullary velum

A

a thin, transparent lamina of white matter, which stretches between the superior cerebellar peduncles

It forms, together with the superior cerebellar peduncle, the ROOF of the upper part of the FOURTH VENTRICLE

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6
Q

Cerebellar peduncle

A

cerebellar peduncle is a nerve tract that permits communication between the cerebellum and the other parts of the central nervous system

superior, middle, and inferior cerebellar peduncles

Superior cerebellar peduncle is a paired structure of white matter that connects the cerebellum to the mid-brain.

Middle cerebellar peduncles connect the cerebellum to the pons and are composed entirely of centripetal fibers.

Inferior cerebellar peduncle is a thick rope-like strand that occupies the upper part of the posterior district of the medulla oblongata; bring sensory information about the actual position of body parts such as limbs and joints.

peduncles form the lateral border of the fourth ventricle, and form a distinctive diamond

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7
Q

Rhomboid fossa

A

a rhombus-shaped depression that is the ANTERIOR part of the fourth ventricle (So rhomboid fossa located on the dorsal side of the brainstem)

anterior wall, formed by the back of the pons and the medulla oblongata, constitutes the floor of the fourth ventricle.

It is covered by a thin layer of grey matter continuous with that of the spinal cord; superficial to this is a thin lamina of neuroglia which constitutes the ependyma of the ventricle and supports a layer of ciliated epithelium.

-projection of the nuclei of cranial nerves in the rhomboid fossa

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8
Q

Brainstem with 4th ventricle

A

exposed by severing cerebellar peduncles and cutting choroid roof away at the margins of the rhomboid fossa

  • 4th ventricle has a diamond shape and is located in the upper portion of the medulla
  • extends from the cerebral aqueduct (of Sylvius) to the obex and is filled with CSF
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9
Q

Cuneate (lateral) and Gracile (medial) tubercle, nuclei, and fasciculus

A

-tubercle is a swelling on the dorsal surface of the medulla caused by presence of nuclei
-fasciculus= bundle of nerve fibers
-ascending tracts: fasciculus gracilis
fasciculus cuneatus

The cuneate fasciculus carries information from vertebral level T6 and above, and the gracile fasciculus carries information from vertebral levels T7 and below. The two ascending tracts meet at the T6 level; pathway by which the sensory modalities of proprioception, vibration, discriminative touch and stereognosis are transmitted from the peripheral receptors of the upper/lower limb and trunk to the primary somatosensory cortex.

cuneate nucleus: cuneocerebellar tract (part of inferior cerebellar peduncle) originates here 
trigeminal tubercle
trigeminal spinal tract (pain and temp)
Chief Sensory Nucleus (touch)
Nucleus of Solitary Tract (taste)
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10
Q

The trigeminal nerve originate from nuclei located where?

A

midbrain and medulla regions of your brainstem

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11
Q

The trigeminal nerve has both sensory and motor components. What do each branch into?

A

sensory root branches into ophthalmic, maxillary, and mandibular divisions

motor root branches into the mandibular division

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12
Q

The midbrain of the brainstem consists of what cranial nerve efferent nuclei?

A

Edinger-Westphal nucleus (parasympathetic of III)

Oculomotor nucleus (somatomotor nucleus)

Trochlear nucleus (somatomotor nucleus)

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13
Q

The pons of the brainstem consists of what cranial nerve efferent nuclei?

A

Trigeminal motor nucleus (upper pons)

Abducens nucleus (lower pons-somatomotor)

Facial motor nucleus (lower pons-branchiomotor)

Superior and Inferior Salivatory nuclei (parasympathetic VII and IX respectively)

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14
Q

The medulla of the brainstem consists of what cranial nerve efferent nuclei?

A

Dorsal vagal motor nucleus (parasympathetic of X)

Nucleus Ambiguus (branchiomotor; IX, X, XI)
IX: stylopharyngeus muscle
X: palatal muscles
XI: laryngeal muscles

Hypoglossal nucleus (somatomotor)

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15
Q

The superior and inferior salivatory nuclei are located in what region of the brainstem?

A

located in the pontine tegmentum in the brainstem which is the dorsal part of the pons, just above its junction with the medulla

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16
Q

What are the parasympathetic cranial nerve efferent nuclei of the brainstem?

A
  • Edinger-Westphal nucleus (III)
  • Superior salivatory nucleus (VII)
  • Inferior salivatory nucleus (IX)
  • dorsal vagal motor nucleus (X)
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17
Q

What are the branchiomotor cranial nerve efferent nuclei of the brainstem?

A

-trigeminal motor nucleus:
muscles of mastication, the tensor tympani, tensor veli palatini, mylohyoid, and anterior belly of the digastric

-Facial motor nucleus:
muscles of facial expression and the stapedius

-Nucleus Ambiguus:
IX: stylopharyngeus muscle
X: palatal muscles
XI: laryngeal muscles

all going to branchial arch muscles

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18
Q

What are the somatomotor cranial nerve Efferent nuclei of the brainstem?

A
  • Oculomotor nucleus
  • Trochlear nucleus
  • Abducens nucleus
  • Hypoglossal nucleus

all right near to the midline of brainstem, right under the ventricles, and right on top of medial longitudinal fasciculus axonal tract

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19
Q

Which cranial nerve Afferent nuclei of the brainstems consists of proprioceptive neurons projecting OUT of V2 and V3? What region of the brainstem is it located?

A

Trigeminal mesencephalic nucleus which is located in the midbrain and pons

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20
Q

Which cranial nerve Afferent nuclei of the brainstems consists of GSA, mainly fine TOUCH from V? What region of the brainstem is it located?

A

Trigeminal main sensory nucleus (chief sensory nucleus) which is located in the pons

-receives information about discriminative sensation and light touch of the face as well as conscious proprioception of the jaw via first order neurons of CN V

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21
Q

Which cranial nerve Afferent nuclei of the brainstems consists of GSA from V, VII, IX, and X? What region of the brainstem is it located?

A

Trigeminal spinal nucleus which is located in the pons and medulla

-receives information about deep/crude touch, PAIN, and TEMPERATURE from the ipsilateral face

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22
Q

Which cranial nerve Afferent nuclei of the brainstems consists of visceral fibers from VII, IX, and X? What region of the brainstem is it located?

A

Nucleus of tractus solitarius which is located in the medulla

  • fibers conveying TASTE sensation project to the Nucleus of Solitary Tract
  • Taste information from the facial nerve via the Chorda tympani (anterior 2/3 of the tongue), glossopharyngeal nerve (posterior 1/3) and vagus nerve (small area on the epiglottis)
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23
Q

Dorsal cochlear nucleus

Ventricular nucleus

A

Dorsal cochlear nucleus:

  • there is also a ventral cochlear nucleus
  • along with the ventral cochlear nucleus (VCN), it forms the cochlear nucleus (CN), where all auditory nerve fibers from the cochlea form their first synapses

Ventricular nucleus:
-vestibular nerve transmits sensory information transmitted by vestibular hair cells located in the two otolith organs (the utricle and the saccule) and the three semicircular canals via the vestibular ganglion

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24
Q

Reticular formation

A

fills in the spaces in between of the nuclei and axonal tracts

  • a diffuse network of nerve pathways in the brainstem connecting the spinal cord, cerebrum, and cerebellum, and mediating the overall level of consciousness.
  • don’t see much in cross-section
  • involved with many functions including the sleep arousal (reticular activating) mechanism, the control of movement and the regulation of visceral activity.
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25
Q

Describe the open vs closed medulla oblongata.

A
  • Open medulla is the upper portion of the medulla oblongata: consists the choroid plexus of the 4th ventricle
  • Closed medulla is the lower portion of the medulla
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26
Q

What axonal tracts connect the cerebellum to the brainstem?

A

cerebellar peduncles: superior, middle, and inferior

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27
Q

Axonal tracts coming FROM the pons TO the cerebellum

A

middle cerebellar peduncle (INTO cerebellum)

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28
Q

Axonal tracts: output of the cerebellum going to the thalamus

A

superior cerebellar peduncle (OUT of cerebellum) through the midbrain

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29
Q

Axonal tracts going from spinal cord and brainstem to cerebellum AND leaving cerebellum and going to spinal cord and brainstem

A

inferior cerebellar peduncle (both OUT and IN of cerebellum)

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30
Q

Cerebral peduncle

A
  • located outside of the midbrain; hide the midbrain from lateral view
  • fiber bundle connecting the hemispheres down to brainstem and spinal cord
  • The cerebral peduncles are involved in numerous functions including somatosensory perception, motor and autonomic control.
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31
Q

Inferior olivary nucleus

A

-close to the obex of the medulla
-inferior olivary nucleus plays an important role in the learning of new motor skills.
bulges out as it is made out of many nuclei
-precerebellar nucleus ????

Posterior to it: roots of CN IX, X, XI
Ventral to it: roots of Hypoglossal nerve

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32
Q

postcerebellar and precerebellar nuclei

A

The term postcerebellar and precerebellar nuclei refers to seven nuclei in the midbrain, pons, and medulla that constitute a functional part of the subcortical motor system of the cerebrospinal trunk. They include the red nucleus, ventral pontine gray, inferior olivary complex, lateral reticular nucleus, linear nucleus of the medulla, ventral paramedian reticular nucleus, and parasolitary nucleus. Functionally they are part of the subcortical motor system

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33
Q

4th ventricle begins and ends where?

A

begins from the trochlear nerve to the obex

-this area of margin contains the rhomboid fossa

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34
Q

What cranial nerves are found at the pontomedullary junction?

A

Cranial Nerve VI (abducens), VII (facial) and VIII (vestibulocochlear nerve)

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35
Q

What cranial nerves are located on the middle cerebellar peduncle?

A

Trigeminal nerve (CN V)

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36
Q

Trigeminal spinal tract

A

somatosensory nuclei mainly on the dorsal side of the medulla

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37
Q

Pyramids

A

descending fibers coming from the cortex

  • physical manifestation of how cortex
  • mediates voluntary motor control

-pyramid is a swelling formed by the corticospinal tract, which controls the speed and precision of skilled movements involving the distal muscles of the contralateral limbs, particularly those of the hands and fingers.

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38
Q

Where is the oculomotor cranial nerve located on the brainstem?

A

just below the inferior colliculus of the midbrain

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39
Q

Branchiomotor nuclei are always ________ to the somatomotor nuclei. Sensory nuclei are located more __________than all the other nuclei.

A

lateral

dorsally

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40
Q

How does the brainstem form embryologically?

A

neatly segmental structure

  • embryonically midbrain and hindbrain neuroepithelium are divided up into a series neuroepithelial segments
  • in the pons and medulla are called rhombomeres (rhomencephalon)
  • you end up with a series of columns: somatic efferent and visceral efferent which make up the basal portion of the brainstem neuroepithelium; visceral afferent and somatic afferent column which make up the alar portion of the brainstem neuroepithelium
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41
Q

Reticular formation of the brainstem

A

everything in the brainstem that is not part of a motor nucleus, sensory nucleus, or precerebellar nucleus

  • a garbage can to dump everything that is not in either one of nuclei
  • not as densely packed as most of the motor and sensory nuclei
  • the different parts of this system are not clearly anatomically defined so most of the parts are described in topographical terms
  • a lot of the nuclei are modulatory meaning they are not in the direct processing train of information
  • there are usually clustered near motor nuclei and receive lots of afferent information
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42
Q

The brainstem reticular formation is organized grossly in a series of neuronal cell columns running more or less continuously from what into the spinal cord? The columns are grouped as? How are the nuclei arranged in each column?

A

thalamus

The columns are grouped as:

  • median (paramedian)
  • medial (central)
  • lateral

The nuclei are distributed rostro-caudally in a general segmental pattern with unique cellular and functional types located at particular axial levels of midbrain, pons, and medulla.

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43
Q

within the median reticular formation

A

this is the particularly in front there are modullary nucleli and most of them are the raphe nuclei which project extensively; include very long projections of serotonergic neurons; modulate motor, somatosensory, limbic, pain circuits;

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44
Q

serotonergic neurons

A
  • part of the overall brainstem arousal system; includes cholinergic and dopaminergic reticular neurons that have strong influence on attention and sleep/wake cycles
  • those located in the rostral raphe complex of mesencephalon and rostral pons project mainly to forebrain targets
  • those located in caudal raphe complex of the caudal pons and medulla project to the brainstem and spinal cord;
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45
Q

raphe nuclei

A
  • the ventral midline structure of the brain and spinal
  • involved in analgesia and pain modulation
  • Serotonergic neurons in nucleus raphe magnus are strongly involved in analgesia and pain modulation through direct projections to the spinal cord dorsal horn.
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46
Q

Nuclei of rostral raphe complex include

A

caudal linear, dorsal raphe and median raphe nuclei

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47
Q

Nuclei of caudal raphe complex include

A

raphe magnus, raphe obscurus and raphe pallidus nuclei

48
Q

medial reticular column

A
  • include numerous nuclei serving premotor functions to organize reticular types of movement
  • in the midline is the oculomotor and trochlear nuclei; neurons that get lots of input from the vestibular and visual system surround them and help organize them in order of the muscles they control
  • vertical gaze: mesencephalic reticular formation
  • horizontal gaze: paramedian pontine reticular formation
  • horizontal head movements: pontomedullary formation

together they form centers for chewing, facial movements, swallowing, etc.

49
Q

major medial reticular nuclei

A
  • cuneiform and subcuneiform nuclei
  • oral pontine reticular nucleus
  • caudal pontine reticular nucleus
  • gigantocellular nucleus of medulla
50
Q

need a premotor neuron to help power motor neuron activity

A

????

51
Q

Lateral Reticular Column

A

Locus Coeruleus
Catecholamine nuclei

A number of noradrenergic and adrenergic nuclei are located in the lateral reticular formation of midbrain, pons and medulla

52
Q

tracts

A

-bundle of axons traveling together like an information cable

53
Q

medial longitudinal fasciulus (MLF)

A

right next to midline and runs up and down the brainstem and entire SC; important in control head and eye movements

  • right near the midline and ventricle next to the central canal
  • hypoglossal motor nucleus sit right on top of the MLF; they do not project into MLF!!; if you want to send info to the hypoglossal motor nucleus send your fibers through MLF

somatomotor nuclei sitting on the MLF (abducens, trochlear, oculomotor); get most of their input from fibers traveling in the MLF

-Longitudinal Fasciculus (MLF) – critical for controlling eye movements; note relationship to nuc. III, IV, VI, XII

54
Q

pyramidal tracts

A

form the pyramids that run on ventral medulla; main tract for voluntary motor control; axon being in motor and premotor cortex and go to corticobulbar fibers in the brainstem

  • corticobulbar projections going to hypoglossal nucleus
  • many of the corticospinal fiber cross at the midline; decussation
  • some stay uncrossed
  • corticospinal tract is a clinically important descending motor pathway/control
  • main tract for voluntary motor control, contains corticospinal and corticobulbar fibers, partially decussates in lower medulla
55
Q

Medial Lemniscus

A

ascending somatosensory pathway

  • in the upper medulla (open medulla)
  • originates in dorsal medial column AKA originate in gracile and cuneate nuclei, forms internal arcuate fibers and decussates in lower medulla, ascends the brainstem to the contralateral thalamus
  • fiber bundle that is spread out like a flat cable
  • axons come out as internal arcuate fibers (meaning they begin dorsally go ventrally and then cross the midline of the brainstem meaning they decussate and go all the way to the contralateral thalamus)

-important in
upper limb and thorax movement

-medial lemniscus transmits sensations of discriminative touch, vibration, proprioception and stereognosis from the gracile and cuneate nuclei to the ventral posterior nucleus of the thalamus

56
Q

lateral lemniscus

A
  • ascending auditory pathway beginning down at the cochlear nuclei going to the inferior colliculi
  • brainstem auditory pathway to inferior colliculus
  • the lateral lemniscus transmits auditory information from the superior olivary and cochlear nuclei to the inferior colliculus.
57
Q

Spinal Medullary junction (lower medulla)

A
  • traditionally called the closed medulla
  • right above the decussation of the pyramids = crossing of the corticospinal fibers
  • a lot of nervous tissue above the roof the of the 4th ventricle and a ton of tracts below the ventricle (pyramidal tracts)
58
Q

tract staining

A

???

all the nuclei will be light

59
Q

This is how you relay somatosensory information

A

tracts of axons with information coming up from the spinal cord synapse in the dorsal column then project to the thalamus

the first thing they do is cross the midline by leaving the dorsal column nuclei as internal arcuate fibers and then enter into the medial lemniscus and turn rostrally and all those are part of the medial lemniscus and will eventually reach the CONTRALATERAL thalamus

Internal arcuate fibres carry tactile and proprioceptive data from the gracile and cuneate nuclei to join the contralateral medial lemniscus.

60
Q

Trigeminal Spinal Tract

A
  • incoming somatosensory info from all the cranial nerves synapse onto the trigeminal spinal nucleus
  • axons run up to the thalamus as well
61
Q

dorsal motor nucleus of vagus

A
  • preganglionic parasympathetic nucleus

- visceral motor

62
Q

solitary tract nucleus

A

the incoming axons of visceral sensory info from cranial mass from CN VII, IX, and X (all those would come in and run down as the solitary and synapse on cells clustered around these tracts AKA solitary tract nucleus

63
Q

dorsal part of the closed medulla; below the roof of the 4th ventricle

A

region totally dedicated to visceral control

-deeply involved in regulation BP and HR

64
Q

inferior olive

A
  • huge nucleus
  • refer to as the precerebellar nuclei
  • gets input from a variety of places but has output goes mostly right to the cerebellum to help regulate neurons there
65
Q

Nucleus Ambiguus

A
  • branchiomotor nucleus of CN IX and X
  • called this because it doesn’t show well on cross section

-in the ventro-lateral medulla which is heavily involved in respiration in concert with reticular formation

66
Q

dorso-lower of closed medulla

A

visceral

67
Q

dorsolateral of closed medulla

A

somatosensory

68
Q

open medulla at the root of the vagus fibers

A
  • there is a choroidal roof of the 4th ventricle

- above the gracile and cuneate nucleus

69
Q

CN X root fibers

A
  • in the open medulla

- dorsal lateral to the inferior olive

70
Q

CN XII root fibers

A
  • in the open medulla

- ventral to the inferior olive

71
Q

vestibular nuclei

A

form a long pyramidal shaped structure ALWAYS dorsal in the brainstem and adjacent to the open port ventricle

incoming root fibers to the vestibular nerve (CN VIIII)

-organized similarly to the premotor system and project appropriately to motor systems to help control balance/posture/head and eye movements

72
Q

inferior cerebellar peduncle

A

???

  • all fibers from the SC and brainstem that want to go to cerebellum AND fibers that want to go from cerebellum to SC and brainstem
  • sits on the lateral surface of the closed medulla
73
Q

pontomedullary junction

A

???

74
Q

caudal pons

A
  • going through the middle cerebellar peduncle
  • ependymal cells surrounding ventricles

-separate pyramids are hidden inside basilar pons

-

75
Q

pontine nuclei

A
  • in caudal pons

- gigantic relay btw cortex and cerebellum (cortex–>pons–>cerebellum)

76
Q

transverse pontine (pontocerebellar fibers)

A

first thing they do is cross the midline (they project to the contralateral cerebellum)

77
Q

middle cerebellar peduncle

A

giant bundle of pontine nuclei neurons forms

-continuous with inferior and superior cerebellar peduncle; can’t really distinguish them until you’ve gone through many sections

78
Q

pontine tegmentum

A

???

79
Q

abducens motor nucleus

A

in caudal pons

  • sits lateral to the MLF
  • somatomotor neurons
80
Q

facial motor nucleu

A
  • above nucleus ambiguus
  • all the motor neurons that innervate stylohyoid, digastric, and all muscles of facial expression, adn stapedius are all in this nucleus
  • then it does this CRAZY thing where the axons from these neurons don’t just pass ventrolaterally to go out of CN root; they instead ascend up towards the ventricle and form a great bundle that wraps around the abducens motor nucleus and make a great exit
  • is reflective of the embryological migration pathway
81
Q

rostral pons

A
  • begin to see the superior cerebellar peduncle
  • 4th ventricle is now narrowing down; see the cerebral aqueduct
  • side walls of the 4th ventricle are made up of the superior cerebellar peduncle (leaving cerebellum going to the thalamus)
82
Q

Trigeminal nucleus and Principal trigeminal nucleus

A
  • lateral tegmentum of upper (ROSTRAL) pons

- tegmentum= area just below the 4th ventricle

83
Q

caudal midbrain

A

trochlear nucleus and decussation of SCP fibers

  • inferior colliculus
  • above the basilar pons
  • enormous fiber bundles on both sides
84
Q

cerebral peduncle

A

-in caudal midbrain

-fibers from cortex going to pontine nuclei
(corticopontine fibers)

  • other fibers form parts of the pyramidal tract running down the SC are corticospinal fibers located centrally of the cerebral peduncle
  • other fibers are corticobulbar fibers running from cortex to motor nuclei of cranial nerves
  • hide midbrain from lateral view
85
Q

interpeduncular fossa

A
  • space in between the between the cerebral peduncles

- where the root fibers of oculomotor come out

86
Q

substantia nigra

A
  • in caudal midbrain
  • deep to the crus cerebri but part of cerebral peduncle
  • substantia nigra plays an important role in the control of movement. It sends dopaminergic fibres to the striatum and when damaged, results in Parkinson’s disease.
87
Q

periaqueductal gray

A

neurons surrounding the cerebral aqueduct

88
Q

tectum

A
  • roof of the midbrain
  • consist of inferior and superior colliculus

-fibers of the inferior colliculus terminate auditory pathway coming up brainstem

89
Q

trochlear motor nucleus

A

????

their axons exits dorsally

90
Q

decussation of superior cerebellar peduncle fibers

A

-in caudal midbrain

can get bilateral deficit if you lesion exactly in the midline of crossing

91
Q

rostral midbrain

A

-harder to distinguish MLF
-Edinger Wesphal nucleus
-oculomotor nucleus whose axons exit through the interpeduncular fossa
-red nucleus
medial geniculate nucleus (thalamus)

92
Q

crus cerebri

A

corticospinal, corticopontine, and corticobulbar fibers together in the cerebral peduncle

93
Q

red nucleus

A
  • called this because they are red
  • important in non-human mammals
  • heavily involved in controlling movements of arms and hands
94
Q

medial geniculate nucleus

A
  • in the rostral midbrain

- gets its input for the inferior colliculus for AUDITORY to go to primary auditory cortex in the hemisphere

95
Q

What are the cranial nerve efferent nuclei associated with CN III?

A

somatomotor nuclei: oculomotor nucleus

visceral (parasympathetic) nuclei: Edinger-Westphal nucleus

96
Q

What are the cranial nerve efferent nuclei associated with CN IV?

A

somatomotor nuclei: trochlear nucleus

97
Q

What are the cranial nerve efferent nuclei associated with CN V?

A

branchiomotor nuclei: trigeminal motor nucleus

98
Q

What are the cranial nerve efferent nuclei associated with CN VI?

A

somatomotor nuclei: abducens nucleus

99
Q

What are the cranial nerve efferent nuclei associated with CN VII?

A

branchiomotor nuclei: facial motor nucleus

visceral (parasympathetic) nuclei: superior salivatory nucleus

100
Q

What are the cranial nerve efferent nuclei associated with CN IX?

A

Branchiomotor Nuclei: rostral part of nucleus ambiguus

Visceral (parasympathetic) Nuclei: inferior salivatory nucleus

101
Q

What are the cranial nerve efferent nuclei associated with CN X?

A

Branchiomotor Nuclei: nucleus ambiguus

Visceral (parasympathetic) Nuclei: dorsal motor nucleus of vagus

102
Q

What are the cranial nerve afferent nuclei associated with CN V?

A

Sensory Ganglia: Trigeminal ganglia

Somatosensory Nuclei: Principal trigeminal sensory nucleus

Visceral sensory Nuclei: Solitary nucleus
(nucleus of the solitary tract)

103
Q

What are the cranial nerve afferent nuclei associated with CN VII?

A

Sensory Ganglia: Geniculate Ganglion

Somatosensory Nuclei: trigeminal spinal nucleus
(nucleus of the trigeminal spinal tract)

Visceral sensory Nuclei: gustatory portion

104
Q

What are the cranial nerve afferent nuclei associated with CN IX?

A

Sensory Ganglia: Sup. & Inf. Sensory ganglia

Visceral sensory Nuclei: Abdominal Visceral portion

105
Q

What are the cranial nerve afferent nuclei associated with CN X?

A

Sensory Ganglia: Sup. & Inf. Sensory ganglia

Visceral sensory Nuclei: Cardio-respiratory portion

106
Q

What are the efferent nuclei related to cranial nerves?

A

Efferent Nuclei

Oculomotor nucleus
Trochlear nucleus
Trigeminal Motor nucleus
Abducens nucleus
Facial Motor nucleus
Nucleus Ambiguus
Hypoglossal nucleus
Spinal accessory nucleus (in spinal cord)
107
Q

What are the afferent nuclei and tracts related to cranial nerves?

A

Afferent Nuclei & Tracts

Trigeminal Sensory Nucleus
Trigeminal Spinal Tract & Nucleus
Mesencephalic Nucleus of Trigeminal

Solitary Tract & Nuclei

Cochlear Nuclei
Vestibular Nuclei

108
Q

What are general somatic afferent nerves? Which cranial nerves carry them?

A

General somatic afferent fibers carry exteroceptive (pain, temperature, touch) and proprioceptive impulses. Cranial nerves for proprioception: III, IV, V, VI, XII; for pain, temperature, and touch: V, VII, IX, X.

109
Q

What are general visceral afferent nerves? Which cranial nerves carry them?

A

General visceral afferent fibers carry impulses from the visceral structures, and cranial nerves IX and X contain these fibers.

110
Q

What are special somatic afferent nerves? Which cranial nerves carry them?

A

Special somatic afferent fibers carry sensory impulses from the special senses (vision, hearing, equilibrium), and cranial nerves II and VIII contain these fibers.

111
Q

What are special visceral afferent nerves? Which cranial nerves carry them?

A

Special visceral afferent fibers carry impulses from the olfactory and gustatory senses, and cranial nerves I (olfactory), VII, IX, and X (gustatory) contain these fibers.

112
Q

What are general somatic efferent nerves? Which cranial nerves carry them?

A

General somatic efferent fibers carry motor impulses to somatic skeletal muscles. In the head, the tongue and extraocular muscles are of this type. Cranial nerves III, IV, VI, and XII carry these fibers.

113
Q

What are general visceral efferent nerves? Which cranial nerves carry them?

A

General visceral efferent fibers carry parasympathetic autonomic axons. The following cranial nerves carry general visceral efferent fibers:

  • Cranial nerve III (Edinger–Westphal nucleus): the preganglionic fibers from the Edinger–Westphal nucleus terminate in the ciliary ganglion, and the postganglionic fibers innervate the pupil.
  • Cranial nerve VII (superior salivatory nucleus): the preganglionic fibers from the superior salivatory nucleus terminate in the pterygopalatine and submandibular ganglion. The postganglionic fibers innervate the lacrimal gland (from the pterygopalatine ganglion) and the submandibular and sublingual gland (from the submandibular ganglion).
  • Cranial nerve IX (inferior salivatory nucleus): the preganglionic fibers from the inferior salivatory nucleus terminate in the otic ganglion, and the postganglionic fibers innervate the parotid gland.
  • Cranial nerve X (dorsal motor nucleus): the dorsal motor nucleus innervates the abdominal viscera.
114
Q

What are special visceral efferent nerves? Which cranial nerves carry them?

A

Special visceral efferent fibers innervate skeletal muscle derived from the branchial arches. They are carried by the following cranial nerves: V (muscles of mastication, first branchial arch), VII (muscles of facial expression, second branchial arch), IX (stylopharyngeus muscle, third branchial arch), X (muscles of the soft palate and pharynx, fourth branchial arch), and XI (muscles of the larynx/sternocleidomastoid (SCM)/trapezius, sixth branchial arch).

115
Q

White matter vs. Gray matter

A

White matter: the paler tissue of the brain and spinal cord, consisting mainly of nerve fibers with their myelin sheaths

Gray matter: darker tissue of the brain and spinal cord, consisting mainly of nerve cell bodies and branching dendrites

116
Q

Basilar Pons

A

The basis pontis is the ventral portion of the pons and contains several descending tracts (corticospinal, corticobulbar and corticopontine) , the pontine nuclei and the transversely oriented pontocerebellar tract

117
Q

14:30

A

?????