Exam 1: Brainstem 2: Pons and Trigeminal Sensory System + some of midbrain (CN nuclei origins diagrams for pons included in Brainstem 1 deck) Flashcards Preview

My Neuroanatomy Behavioral Neurosciences > Exam 1: Brainstem 2: Pons and Trigeminal Sensory System + some of midbrain (CN nuclei origins diagrams for pons included in Brainstem 1 deck) > Flashcards

Flashcards in Exam 1: Brainstem 2: Pons and Trigeminal Sensory System + some of midbrain (CN nuclei origins diagrams for pons included in Brainstem 1 deck) Deck (52):
1

Identify the landmark or structure

Pyramid

2

Identify the landmark or structure

Decussation of Pyramids*

*At the caudal medulla, where the corticospinal tracts decussate!

3

Identify the landmark or structure

Dorsal root of spinal nerve

 

4

Identify the landmark or structure

Gracile fasciculus

 

5

Identify the landmark or structure

Spinal accessory nucleus (CN XI)

 

6

Identify the landmark or structure

Medial motor nuclei

 

7

How far down does the trigeminal tract go?

What is it analogous with?

the trigeminal tract goes all the way into the spinal cord

it becomes analogous with Lissauers tract

8

Identify the landmark or structure

Solitary nucleus (CN VII, IX, X)

 

9

Identify the landmark or structure

Spinal trigeminal nucleus (CN V, VII. IX, X)

 

10

Identify the landmark or structure

Solitary nucleus (CN VII, IX, X)

 

11

Identify the landmark or structure

Spinal trigeminal nucleus (CN V, VII. IX, X)

 

12

What does the red line represent?

What nuclei are found lateral to the line? medial?

The red line is the sulcus limitans

Lateral to the sulcus limitans are the sensory nuclei

Medial to the sulcus limitans are the motor nuclei

13

Identify the landmarks or structures of the Pons marked by the red and yellow stars

The red star is the basal portion of the pons

The yellow star is the Tegmental portion (ventral to the 4th ventricle)

14

Identify the landmark or structure

Facial colliculus

 

15

What are the Major Longitudinal Regions of the Pons (“Bridge”)

 

Basal Pons (Basis Pontis)

and

Pontine Tegmentum

16

What are the major components of the Basal Pons (Basis Pontis)

 

Corticospinal and corticobulbar tracts (descending)

Pontine nuclei (cerebellar circuitry)

17

What are the major components of the Pontine Tegmentum

 

• Is separated from cerebellum via 4th Ventricle

Cranial nerve nuclei

Reticular formation

Medial lemniscus (ascending pathway heading to VPL of thalamus)

MLF (mostly ascending here; keeps dorsomedial position)

18

Whats unique about the Pons?

Reticular formation in medulla and caudal pons involved in _____ and _____ functions.

Large, lateral connections with cerebellum via superior and middle _____ _____

Shares vestibular nuclei of CN VIII with medulla (at _____ junction)

Nuclei of CN ___, ___, and ___

Whats unique about the Pons?

Reticular formation in medulla and caudal pons involved in motor and autonomic functions (also sleep, wakefullness, conciousness).

• Large, lateral connections with cerebellum via superior and middle cerebellar peduncles (hence, “bridge”)

Shares vestibular nuclei of CN VIII with medulla (at pontomedullary junction)

• Nuclei of CN VII, VI, V

19

Identify the landmark or structure

Corticospinal and corticobulbar tracts

 

20

Identify the landmark or structure

Medial longitudinal fasciculus (MLF)

NOTE: medial longitudinal fasiculus, connects vestibular and cochlear nuclei to nearby nuclei controlling extraocular muscles (III, IV, VI)

21

Identify the landmark or structure

Facial colliculus

 

22

Identify the landmark or structure

Nucleus of abducent nerve

 

23

Identify the landmark or structure

Motor nucleus of facial nerve

 

24

Identify the landmark or structure

Facial nerve

 

25

Identify the landmark or structure

Abducent nerve

 

26

Identify the landmark or structure

Transverse pontine fibers

 

27

Study the cross section of the rostral to mid pons  nd be able to recognize the major landmarks and structures

Study the cross section of the rostral to mid pons and be able to recognize the major landmarks and structures

28

Study the cross section of the Pontomesencephalic Junction and be able to recognize the major landmarks and structures

Study the cross section of the Pontomesencephalic Junction and be able to recognize the major landmarks and structures

29

Identify the landmark or structure

Cerebral aqueduct

30

Identify the landmark or structure

Pontine nuclei

31

Identify the landmark or structure

Pontocerebellar fibers

32

Identify the landmark or structure marked by the red star

Tectum

33

Identify the landmark or structure

Tegmentum

34

Identify the landmark or structure

Oculomotor nerve

35

Identify the landmark or structure

Cerebral aqueduct

36

Which section of the brain stem is between the red dotted lines?

Midbrain

 

37

Identify the landmark or structure

Superior colliculus*

 

*note there are 2 Superior colliculi and 2 Inferior colliculi; together the 4 colliculi are collectively called corpora quadrigemina (four bodies)

38

Identify the landmark or structure

Inferior colliculus*

 

*note there are 2 Superior colliculi and 2 Inferior colliculi; together the 4 colliculi are collectively called corpora quadrigemina (four bodies)

39

Identify the landmark or structure

Trochlear nerve (CN IV)

 

Note: The trochelar nerve is the only CN that exits the brain stem dorsally!

 

40

Identify the landmark or structure

Crus cerebri

41

Identify the landmarks or structures marked by the red and yellow stars

The yellow star is Tectum

The red star is Tegmentum

42

The Trigeminal Ganglia consist of primary _____ neurons, with one exception:

_____ is both motor and sensory

The Trigeminal Ganglia* consist of primary sensory neurons, with one exception:

V3  mandibular is both motor and sensory

 

43

Review the functions of V1, V2, amd V3!!!

 

What else does CN V provide sensation for?

 

Review the functions of V1, V2, amd V3!!!

 

 CN V also provides sensation for supratentorial dura!

44

What else does CN IX provide sensation for?

 

 CN IX also provides sensation for  the middle ear, posterior 1/3 tongue, and pharynx.

45

What else does CN X provide sensation for?

 

 CN X also provides sensation for infratentorial dura and probably pharynx, too

46

What are the 3 Trigeminal Nuclei in the brainstem?

 

Trigeminal Nuclei:

1. Mesencephalic

2. Chief or (Principal)

3. Spinal

47

Trigeminal Nuclei:

• the spinal trigeminal nucleus runs in the same column as the _____ _____ of the spinal cord.

Trigeminal sensory column” is analogous to _____ and _____ “systems” of the spinal cord.

Trigeminal Nuclei:

• the spinal trigeminal nucleus runs in the same column as the dorsal horn of the spinal cord.

Trigeminal sensory column” is analogous to DC-ML and anterolateralsystems” of the spinal cord.

48

General somatic sensory mainly from _____ and a little from ___, ___, and ___

General somatic sensory mainly from CN V and a little from VII, IX, and X (at ear).

49

Where does brainstem fit into 3-neuronal sensory pathway???

Where does brainstem fit into 3-neuronal sensory pathway???

50

Know and understand this chart

Know and understand this chart

51

Mesencephalic Trigeminal Nucleus:

• Here’s the exception: _____ _____ nucleus is located in the CNS/brainstem.

Receive _____ input from muscles of mastication, tongue, extraocular muscles

Clinical Relevance: Involved in _____ _____ reflex

Mesencephalic Trigeminal Nucleus:

•Here’s the exception: Primary sensory nucleus is located in the CNS/brainstem.

• Receive proprioceptive input from muscles of mastication, tongue, extraocular muscles

Clinical Relevance: Involved in jaw jerk reflex*

 

• In this reflex, there are fibers that run from the mesencephalic nucleus DOWN to the pons to the MOTOR NUCLEUS of V (that ultimately innervate muscles of mastication via the mandibular division of V3)

• Other roles of this nucleus are “under investigation”

52

Note DECUSSATION in Secondary Neurons!!!

Note DECUSSATION in Secondary Neurons!!!

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