Exam 3 Flashcards

0
Q

At what age will the tip of the dens center of ossification appear?

A

Sometime in early adolescence

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1
Q

What is the name given to the joint formed between the tip of the dens and the odontoid center of ossification?

A

Tip of the dens synchondrosis

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2
Q

If the joint formed between the tip of the dens and odontoid proces centers of ossification persists beyond age 12, what is the condition called?

A

Terminal ossicle

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3
Q

What is the incidence of rib related changes following dorsalization of c7?

A

From one-half to two and one-half percent of the population

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4
Q

What alteration in C6 facet orientation may accompany dorsalization?

A

C6 demonstrates a change in inferior articular facet orientation from forward lateral and downward to forward medial and downward. Superior facet unchanged

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5
Q

What percent of the population may demonstrait thoracic like features at C7?

A

Up to 46%

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6
Q

What T1 facet orientation changes may accompany cervicalization?

A

The superior articular facet may change from BUL to BUM inferior unchanged

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7
Q

What is the incidence of cervicalization of T1 in the population?

A

Up to 28% of population

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8
Q

What rib-related changes may accompany lmbarization of T12?

A

A significant shortening of the mean relative length of 113 mm of the twelfth rib or it becomes absent

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9
Q

What T12 facet orientation changes may accompany lumbarization?

A

The superior araticular facet may change from flat, back, upward, and lateral to concave, back, upward, and medial. Inferior facet unchanged

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10
Q

What is characteristic of lumbarization of S1?

A

The failure of synostosis between S1 and S2, squaring of the vertebral body of S1 and flaring of the sacral ala

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11
Q

What is characteristic of sacralization of L5?

A

L5 may be partially or completely fused to the sacrum

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12
Q

Which segment demonstrates the greatest morphological variation along the spine?

A

L5

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14
Q

What is the incidence of variation within the sacrococcygeal region in the population?

A

Up to 14 percent

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15
Q

What developmental events are indicated in the formation of the adult cervical spine?

A

Centers for vision and equilibrium will appear in the brain musculature attaching the skull, cervical region, and upper thorax together develops the head is held upright and the intervertebral disc height becomes greater anterior than posterior

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16
Q

At what age will the infant begin to hold the head erect?

A

Usually between the third and fourth month after birth.

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17
Q

What is the location for the cervical kyphosis?

A

Between occiput and C1

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18
Q

What is the name given to the primary cervical curve?

A

Cervical kyphosis

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19
Q

What is the name What is the vertebral relationship between the cervical curve and the cervical enlargement?

A

Cervical curve CT1; cervical enlargment C3-T1

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20
Q

What infant activities are associated with the developmental of the lumbar curve?>

A

Crawling and walking

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21
Q

What developmental events are indicated in the formation of the adult lumbar curve?

A

crawling will cause abdomen to put tension on lumbar region and pulls it forward

Muscle development is promoted to compensate for the swayback of the lumbars

Intervertebral disc height will become greater anterior compared to posterior

walking will further promote muscle and IVD development

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22
Q

What is the time of appearance of the lateral curves?

A

They appear after 6 years old

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23
Q

What is the relationship between cure direction and handedness?

A

Right handed person has a high probability for right thoracic, left lumbar combo

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24
Q

What clinical examples of abnormal curvatures aloneg the vertebral column were stressed in class?

A

Military neck, humpback or hunchback, or swayback

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25
What is military neck?>
Decreased anterior curve in the cervical region, a straight neck
26
What is a swayback?
An increased anterior curve in the lumbar region
27
What are the curve classifications for military neck?
A kyphosis or hypolordotic curve
28
What are the curve classifications for humpback or hunchback?
A kyphosis or hyperkyphotic curve
29
What are the curve classifications for swayback?
A lordosis or hyperlordotic curve
30
What are the classifications of scoliosis according to the Scoliosis Research Society?
Magnitude, Location, Direction, Etiology, and structural/non-structural
31
What is often used to measure the magnitude of scoliosis?
The Cobb Method
32
Based on age of onset, what are the types of idiopathic scoliosis
Infantile, Juvenile, and adolescent
33
Identify the curve direction, location, gender bias and incidence of infantile idiopathic scoliosis
Left thoracic, male, less than 1% incidence
34
Identify the curve direction, location, gender bias and incidence of juvenile idiopathic scoliosis
Right thoracic, females over 6 years old, 12 % - 21% incidence
35
Identify the curve direction, location gender bias and incidence of adolescent idiopathic scoliosis
Right thoracic or right thoracic and left lumbar, females, 80% incidence
36
What is the relationship between curve deviation, incidence, and curve worsening
The greater the deviation, the lower the incidence, the more likely to worsen
37
Which muscles are identified as erector spine or sacrospinalis muscles?
Iliocostalis, Longissimus, Spinalis
38
Which subdivision of the iliocostalis primarily originates and inserts on ribs?
Iliocostalis Thoracis
39
Which muscles are identified as transversospinalis muscles?
semispinalis, multifidis, and rotators
40
How many vertebrae can be attached to a single segment by transversospinalis muscles?
As many as nine vertebrae
41
What segment will represent the lowest attachment site for the semispinalis thoracics?
T12
42
What osseous parts of the vertebral column serve as an origin to the semispinalis capitis?
Transverse tubercles of C7, T1-T6 or T7 & articular processes of C4-C6
43
The semispinalis capitis and spinals capitis may fuse to form what muscle?
Biventer Cervicis
44
Which muscles are representative of muscle layer two in the neck?
Splenius cervicis, splenius capitis
45
Which muscles are representative of muscle layer three in the neck
Semispinalis capitis, spinais capitis
46
Which transversospinalis muscle attaches to articular and mammillary processes along the spine?
Multifidis
47
Which muscles of the spine exhibit a reversal of the expected origin - insertion combination?
Iliocostalis lumborum pars lumborum, longissimus thoracic pars lumborum and multifidus lumborum
48
Which sub occipital muscle lacks an attachment to the skull?
Oblique capités inferior
49
What is the origin go the obliquus capitis inferior
C2 spinous process and lamina
50
An increase in the density of muscle spindles is most apparent in which sub occipital muscle?
Obliquus capités inferior
51
Suboccipital muscle feedback relays to what aditional locations in the brain?
Extraocular nuclei of origin, primary visual cortex and vestibular nuclei
52
What is the proposed function of the suboccipital muscle group?
Postural stabilizers of the atlanto-occipital and atlanto-axial joints
53
Based on the density of muscle spindles what is the proposed function of the interspinalis?
Acts as a proprioceptive transducer in conjunction with intertransversarii to coordinate the smooth movment of the spine and to maintain appropriate posture
54
WHich of the cervical intertransversarii is intervated by dorsal rami of cervical spinal nerves?
Posterior medial belly, cervical intertransversarii
55
What is the origin of the medial belly of the lumbar intertransversarii?
Accessory process of transverse process L1-L4 mammillary process of superior articular process L1-L4
56
Which of the lumbar intertransversarii is innervated by dorsal rami of lumbar spinal nerves?
Medial belly, lumbar intertransversarii
57
Based on the density of muscle spindles what is the proposed function of the intertransversarii?
Acts as a proprioceptive transducer in conjunction with interspinalis to coordinate the smooth movment of the spine and to maintain appropriate posture
58
What is the insertion of the middle scalene?
Between the tubercle and groove for the subclavian artery on the first rib
59
What is the insertion of the posterior scalene?
Outer surface of second rib
60
The quadratus lumborum is implicated in the formation of which ligament?
The iliolumbar ligament
61
What are the possible locations of bipolar neurons?
The nasal olfactory epithelium, the retina, the vestibular or Scarp's ganglion, and the chochlear or spiral ganglion
62
What are the possible locations of pseudounipolar neurons?
Any sensory ganglion other than those of the eighth cranial nerve
63
What are the examples of multipolar neurons?
Stellate neurons, the motor neurons of brain and spinal cord Pyrmidal neurons of cerberal cortex Projection neurons or Golgi type 1 Purkinje cells of cortex Local circuit neurons or Golgi 2 granule cells of cerebral and cerebellar cortex and neurons of the motor ganglia
64
What do baroreceptors monitor?
Blood pressure by evaluating stretch or tension along the length of the receptor ending
65
What is the site or location for baroreceptors?
Specialized vascular sinuses
66
What are the general types of distribution-function sensory receptor endings?
Exteroceptors, proprioceptors, interoceptors
67
What are the types and examples of exteroceptors?
(a) general or cutaneous sense organs such as free nerve endings, encapsulated endings and epidermal endings (b) special sense receptors for olfaction, vision, hearing and taste
68
What are the examples of proprioceptors?
Golgi tendon organs, neuromuscular spindles, Pacinian corpuscles, inner ear receptors for equuilibrium and specialized receptors in joints
69
Where will the interoceptors be located?
In viscera, glands, and blood vessels
70
What are the examples of interoceptors?
Free nerve endings, encapsulated nerve endings, chemoreceptors and baroreceptors
71
What are the examples of epidermal nerve endings?
Palisade nerve endings, Merkel cell endings and Ruffini corpuscles or Ruffini nerve endings
72
What is the example of tactile corpuscles?
Meissner's corpuscles
73
Which type of encapsulated nerve ending is sensitive to vibration?
Lamellated corpuscles or Pacinian corpuscles
74
What is the example of the neurotendinous nerve ending?
Golgi tendon organs
75
What are the primary neuronal projections observed in a nerve?
Peripheral sensory processes and motor nerve fibers
76
Contrast the sensory ganglion with the motor ganglion
Sensory ganglia contain primary sensory neuron cell bodies and lack synapses; motor ganglia contain secondary motor neuron cell bodies and always demonstrate synapses
77
What is another name for a sensory neuron?
Afferent neuron
78
What are the parts of a primary sensory neuron?
Sensory receptor ending, peripheral sensory process, perikaryon, central sensory process, synaptic ending
79
Where is the cell body of a primary sensory neuron located?
In a sensory ganglion
80
What is the region in the encephalon where central sensory processes synapse?
Nucleus of termination
81
What is the loction for secondary sensory neurons in the spinal cord?
Dorsal horn
82
Muscles derived from somites are innervated by which cranial nerves?
Cranial nerve 3 or oculomoter nerve, cranial nerve 4 or trochlear nerve, cranial nerve VI or abducens nerve and cranial nerve XII or hypoglossal nerve
83
Muscles derived from the branchial or pharyngeal arches are innervated by which cranial nerves?
Cranial nerve V or trigeminal nerve, cranial nerve VII or facial nerve, cranial nerve IX or glossopharyngeal nerve, cranial nerve X or vagus nerve and cranial nerve XI or spinal accessory nerve
84
What peripheral nerves contain visceral efferent pathways at their origin?
Cranial nerve III or oculomotor nerve, cranial nerve VII or facial nerve, cranial nerve IX or glossopharyngeal nerve, cranial nerve X or vagus nerve as well as spinal nerves T1-T12, L1, L2 and S2-S4
85
Identify the type of motor pathway associated with each type of muscle
Somatic and branchial motor pathways terminate on skeletal muscle autonomic/involuntary/visceral pathways terminate on smooth and cardiac muscle
86
What are the subdivisions of the visceral division of the peripheral nerve system?
Sympathetic, parasympathetic, and enteric
87
What is the region in the central nerve system where sympathetic efferent neuron cell bodies for spinal nerves are located?
Lateral horn of T1-T12, L1, L2 cord levels
88
What is the comparative length of the axons associated with the sympathetic efferent pathway?
Preganglionic sympathetic efferent fibers are relatively short; postganglionic sympathetic efferent fibers are relatively long
89
What cells derived from the neural crest where emphasized in class?
Secondary sympathetic efferent neurons and adrenal medulla chromaffin cells
90
Primary parasympathetic efferent neurons will be associated with which cranial nerves?
Cranial nerve III or oculomotor nerve, cranial nerve VII or facial nerve, cranial nerve IX or glossopharyngeal nerve and cranial nerve X or vagus nerve
91
Primary parasympathetic efferent neurons will be associated with which spinal nerves?
Spinal nerves S2-S4
92
What is the name given to and neuroactive substance associated with postganglionic parasympatheic efferent pathways?
Cholingeric fibers; acetylcholine
93
What is the comparative length of the axons associated with parasympathetic efferent pathways?
Preganglionic parasympathetic efferent fibers are relatively long; Postganglionic parasympathetic efferent fibers are relatively short
94
Sesker is a Homo
...Duhh lol
95
What types of efferent neurons form nuclei of origin in the brain?
Somatic neurons, brachial neurons, and primary parasympathetic neurons
96
Will sympathetic efferent neurons be located in the brain?
No
97
What are the target organs for branchial efferents or somatic efferents?
Skeletal muscles
98
What are the ultimate target organs for parasympathetic efferents?
Smooth muscle, cardiac muscle, glandular tissue, and specialized cells
99
Which cranial nerves have sensory pathways that are atypical of the majority of sensory pathways?
Olfactory or cranial nerve I, optic or cranial nerve II, and trigeminal or cranial nerve V
100
What do somatic afferents monitor?
Pain, Temperature, light touch and proprioception
101
What do visceral afferents monitor?
Baroreception, chemoreception, sensation from viscera
102
What do special visceral afferents monitor?
Olfaction and taste
103
What do special sensory afferents monitor?
Vision, hearing, equilibrium
104
Cranial nerve I is an example of which classification of sensory pathway?
Special visceral afferent
105
What is the site for the detection of smell?
The olfactory mucosa of the nasal cavity
106
What is the morphological classification of the primary sensory neuron of the first cranial nerve?
Bipolar neuron
107
What is unusual about the receptor ending of the primary olfactory neuron?
It is an olfactory knob covered with olfactory cilia
108
What do central processes of the first cranial nerve bundle together to form?
Fila Olfactoria
109
What forms the true olfactory nerve?
Fila Olfactoria
110
What forms the traditional or classic first cranial nerve?
The olfactory bulb and olfactory tract
111
What is the exit site for the first cranial nerve?
Cribiform plate of the ethmoid bone
112
Secondary afferent neuron cell bodies of the first cranial nerve are primarily located in what structure?
Olfactory Bulb
113
What is the location for synapse between primary and secondary afferent neurons of the first cranial nerve?
Olfactory Glomerulus
114
What is the name of the traditional secondary afferent neuron of the first cranial nerve?
Mitral cell
115
Cranial nerve II is an example of which classification of sensory pathway?
Special sensory
116
What are the receptor neurons of the second cranial nerve?
Rod and cone photoreceptor cells
117
What is the function of the cone cell?
Provide vision in bright light conditions and mediate color vision
118
What is the function of the rod cell?
Provide vision in dim light conditions
119
What is the most numerous photoreceptor cell?
Rods
120
What is the primary afferent neuron of the second cranial nerve>
Bipolar cell
121
Where are the primary sensory neurons of the second cranial nerve located?
The retina
122
What is the secondary sensory neuron of the second cranial nerve?
Ganglion Cell
123
What forms the optic nerve?
Axons of ganglion cells
124
What is the exit site for the second cranial nerve?
Optic canal of the sphenoid bone
125
The optic nerve will enter which fossa of the cranial vault?
Middle cranial fossa
126
What occurs at the optic chiasma?
Part of the optic nerve decussates
127
What part of the visual pathway connects the optic chiasma to the brain?
The optic tract
128
Axons carried in the second cranial nerve will synapse in what specific location?
Lateral geniculate nucleus
129
What is the location for tertiary neurons of the visual pathway?
Lateral geniculate nucleus
130
Axons from the lateral geniculate nucleus will synapse in what specific location?
Primary visual cortex, calcarine sulcus of the occipital lobe of the cerebrum
131
At its apparent origin cranial nerve III conveys which classifications of neural pathways?
Somatic efferent pathway and visceral efferent pathway
132
What is the somatic efferent nucleus of origin for the third cranial nerve?
Oculomotor nuclear complex
133
What is the location of the apparent origin of the third cranial nerve?
The midbrain
134
The apparent origin of the third cranial nerve is first observed in which cranial fossa?
The posterior cranial fossa
135
What is the exit from the cranial vault for the third cranial nerve?
Superior orbital fissure; Sphenoid bone
136
Which extrinsic muscle/s of the eye is/are innervated by the third cranial nerve?
Medial rectus, inferior rectus, superior rectus, and inferior oblique
137
Which non-ocular muscle is innervated by the third cranial nerve?
Levator palpebrae superioris muscle of the eyelid
138
Which visceral efferent pathway is conveyed in the third cranial nerve?
A parasympathetic motor pathway
139
Visceral efferent pathway is conveyed in the third cranial nerve originate from which nucleus?
Accessory oculomotor nucleus of Edinger/Westphal
140
What is the location of synapse for preganglionic parasympathetic efferent fibers of the third cranial nerve?
Ciliary ganglion
141
Postganglionic parasympathetic efferent fibers of the third cranial nerve are carried in which nerve?
Short cilia nerve
142
Postganglionic parasympathetic efferent fibers of the third cranial nerve synapse in what targets?
Sphincter pupillae & ciliaris intrinsic eye muscles
143
Does the apparent origin of cranial nerve III contain somatic afferent fibers?
No
144
Peripheral sensory processes conveyed in the third cranial nerve will communicate with which cranial nerve branch?
Ophthalmic division of trigeminal
145
Peripheral sensory processes conveyed in the third cranial nerve travel to pseudo unipolar sensory neuron cell bodies located in which ganglion?
Gasserian ganglion, semilunar ganglion or trigeminal ganglion
146
Central sensory processes from the Gasserian ganglion, semilunar ganglion or trigeminal ganglion are conveyed to the pons in what structure?
The sensory root of the trigeminal nerve
147
The sensory root of the trigeminal nerve will have an apparent origin from what part of the encephalon?
The pons
148
Typically, primary afferent neurons of the third cranial nerve located in the semilunar ganglion, Gasserian ganglion or tirgeminal ganglion will synapse in what nucleus?
Spinal trigeminal nucleus
149
Which of the cranial nuclei of termination contain primary afferent neurons?
Mesencephalic nucleus of the trigeminal nerve
150
In the somatic afferent pathway of cranial nerve III, neurons within the mesencephalic nucleus may synapse at what locations?
Oculomotor nuclear complex or spinal trigeminal nucleus
151
At its apparent origin cranial nerve IV conveys which classification of neural pathways?
Somatic efferent pathway
152
What is the location for multipolar somatic efferent neurons of the fourth cranial nerve?
Trochlear motor nucleus
153
Somatic efferent fibers from the left nucleus of the fourth cranial nerve will have an apparent origin from which side?
Right side
154
What are the two unique features of the fourth cranial nerve?
It is the only cranial with an apparent origin from the dorsal surface of the brain; it is the only cranial efferent nerve to decussate within the midbrain from its nucleus
155
The right fourth cranial nerve will innervate which side target muscle?
The right side muscle
156
The fourth cranial nerve wil originiate in which cranial fosssa?
The posterior cranial fossa
157
The fourth cranial nerve exits the cranial vault by way of which opening?
Superior orbital fissure; sphenoid bone
158
Somatic efferent fibers from the fourth cranial nerve will innervate which muscle(s)?
Superior oblique extrinsic muscle of the eye
159
Does the apparent origin of cranial nerve IV contain somatic afferent fibers?
No
160
What part of the fourth cranial nerve contains somatic afferent fibers?
Only the distal part of the nerve
161
Peripheral sensory processes conveyed in the fourth cranial nerve will communicate with which cranial nerve branch?
Ophthalmic division of trigeminal
162
Peripheral sensory processes conveyed in the fourth cranial nerve travel to pseudo unipolar sensory neuron cell bodies located in which ganglion?
Gasserian ganglion, semilunar ganglion or trigeminal ganglion
163
The fifth cranial nerve is functionally referred to as the
Great sensory nerve of the face
164
The fifth cranial nerve arises from what part of the brain?
The pons
165
The apparent origin of the fifth cranial nerve is in which cranial fossa?
The posterior cranial fossa
166
Identify each branch of the fifth cranial nerve arising from its ganglion
Ophthalmic nerve, maxillary nerve, mandibular nerve
167
What is the exit site from the cranial vault for each division of the fifth cranial nerve?
Ophthalmic nerve - superior orbital fissure, maxillary nerve - foramen rotundum, mandibular nerve - foramen ovale
168
What location will each branch of the fifth cranial nerve pass into upon exit form the cranial vault?
Ophthalmic nerve - orbit; maxillary nerve - pterogyopalatine region; mandibular nerve - infratemporal region
169
The motor root of cranial nerve V will join which division?
Mandibular nerve
170
At its apparent origin cranial nerve V conveys which classification of neural pathways?
Somatic afferent pathway and branchial efferent pathway
171
Which divisions of the trigeminal nerve contain somatic afferent pathways?
All three
172
Central sensory processes carried in the fifth cranial nerve synapse with secondary sensory neuron cell bodies in what location?
Mainly in the principal sensory nucleus; some in the trigeminal spinal nucleus
173
Branchial efferent fibers arise from multipolar neurons in what nucleus?
Trigeminal motor nucleus
174
The mandibular division of the fifth cranial nerve exits the cranial vault via which opening and enters into what region of the head?
The foramen oval; the infra temporal region
175
What muscles are innervated by branchial efferent fibers conveyed in the fifth cranial nerve?
Temporalis, masseter, medial pterygoid, lateral pterygoid, mylohyoid, anterior belly of the digastric, tensor tympani and tensor veil palatini
176
What are the names of the muscles of mastication?
Temporalis, masseter, medial pterygoid, lateral pterygoid
177
Peripheral sensory process from which receptors located in the muscles of mastication are conveyed in which branch of the fifth cranial nerve?
Mandibular division of trigeminal
178
Afferent neurons within the mesencephalic nucleus that are associate with sensation from the muscles of mastication will synapse at what locations?
Trigeminal motor nucleus or spinal trigeminal nucleus
179
At its apparent origin cranial nerve VI conveys which classification of neural pathways?
Somatic efferent pathway
180
What is the name of the sixth cranial nerve?
Abducent nerve or abducens nerve
181
What is the site of the apparent origin of the sixth cranial nerve from the brain?
The pons
182
What is the efferent nucleus for the sixth cranial nerve?
Abducens motor nucleus or abducent motor nucleus
183
The sixth cranial nerve will innervate what target organ (s)?
Lateral rectus extrinsic muscle of the eye
184
Peripheral sensory process conveyed in the sixth cranial nerve travel to pseudo unipolar sensory neuron cell bodies located in which ganglion?
Gasserian ganglion, semilunar ganglion, or trigeminal ganglion
185
Peripheral sensory process conveyed in the sixth cranial nerve will communicate with which cranial nerve branch?
Ophthalmic division of trigeminal nerve
186
Typically, primary afferent neurons of the sixth cranial nerve located in the semilunar ganglion, Gasserian ganglion or trigeminal ganglion will synapse in what nucleus?
Spinal trigeminal nucleus
187
Recently, peripheral sensory processes conveyed in the sixth cranial nerve have been shown to originate from primary afferent neurons in which location?
Mesencephalic nucleus of the trigeminal nerve
188
Which of the cranial nuclei of termination contain primary afferent neurons?
Mesencephalic nucleus of the trigeminal nerve
189
In the somatic afferent pathway of cranial nerve VI, neurons within the mesencephalic nucleus may synapse at what locations?
Abducent or abducens motor nucleus or spinal trigeminal nucleus