Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BAB > A04 Brainstem Nuclei and Cranial Nerves > Flashcards

A04 Brainstem Nuclei and Cranial Nerves Flashcards

1
Q

List the components of the brainstem.

A

1 - Medulla oblongata.

2 - Pons.

3 - Midbrain.

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

Through which structure does the brainstem join the spinal cord?

A

The foramen magnum.

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

Which structures enable communication with the cerebellum?

Where are these structures located?

A
  • The superior, middle and inferior cerebral peduncles.

- They are located on the dorsal surface of the brainstem.

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

What do the cerebral peduncles contain?

A

The portion of the ascending and descending nerve tracts that pass between the cerebrum and pons.

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

What is the crus cerebri?

A

The anterior portion of the cerebral peduncles which primarily (but not exclusively) contains motor tracts.

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

List 4 discrete grey areas within the brainstem.

A

1 - Cranial nerve nuclei.

2 - Reticular formation.

3 - Olivary nuclei.

4 - Cuneate nuclei.

5 - Gracile nuclei.

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

What is the reticular formation?

Describe its course in the CNS.

A

A network of neurones that extends from:

1 - The spinal cord.

2 - To the dorsal brain stem.

3 - To the tegmentum of the midbrain.

4 - Terminating in the thalamus.

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

What is the function of the reticular formation?

List 7 structures with which the reticular formation synapses in order to carry out its function.

A
  • The reticular formation has some control over which sensory signals reach the cerebrum and come to our conscious attention.
  • It is able to do this by synapsing with:

1 - The spinoreticular tract.

2 - The spinothalamic tracts.

3 - The medial lemniscus.

4 - Cranial nerve nuclei.

5 - The cerebellum.

6 - Subthalamic, hypothalamic and thalamic nuclei.

7 - Both the primary motor and sensory cortices of the cerebral cortex.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

List the components of the descending tracts that are influenced by the reticular formation.

A

1 - Reticulobulbar tracts (parasympathetic outflow).

2 - Reticulospinal tracts (parasympathetic outflow).

3 - The corpus striatum.

4 - The cerebellum.

5 - The red nucleus.

6 - The substantia nigra.

7 - The tectum.

8 - Nuclei of the diencephalon.

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

Give an example of an adaptation of the reticular formation.

A

The neurones have unusually long dendrites which maximise their ability to receive and integrate synaptic outputs from most of the fibres that extend through the brainstem.

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

What is the medial lemniscus?

A

A large ascending bundle of heavily myelinated axons formed by the internal arcuate fibres that decussate in the medulla oblongata.

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

What is the red nucleus?

What gives the red nucleus its colour?

A
  • A nucleus in the rostral midbrain that is involved in motor coordination.
  • The colour is due to the presence of iron in haemoglobin and ferritin.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the substantia nigra?

A

One of the 6 nuclei composing the basal ganglia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

List the nuclei composing the basal ganglia.

A

1 - Substantia nigra.

2 - Caudate nucleus.

3 - Lentiform nucleus.

4 - Amygdala.

5 - Claustrum.

6 - Subthalamic nucleus.

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

What is the corpus striatum?

A

The collective name given to the caudate nucleus and lentiform nucleus of the basal ganglia.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

List 3 influences of the reticular formation on the control of skeletal muscle.

A

1 - The reticular formation modulates muscle tone and reflex activity via the reticulospinal and reticulobulbar tracts.

2 - The reticular formation is involved in reciprocal inhibition (when flexors contract, antagonist muscles must relax).

3 - The reticular formation and vestibulospinal tract are together responsible for maintaining the tone of antigravity muscles when standing.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

List the structures through which the reticular formation exerts an influence on the autonomic nervous system.

A

1 - Reticulospinal tracts.

2 - Reticulobulbar tracts.

*These are descending tracts which descend to sympathetic and parasympathetic outflow.

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

How does the reticular formation exert an influence on the endocrine system?

A

By directly and indirectly influencing hypothalamic nuclei, which controls the secretions of the pituitary gland.

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

Describe the reticular activating system.

A
  • Ascending pathways project information to the reticular formation.
  • The reticular formation integrates the information and, if appropriate, will arouse an individual to a more alert state (for example waking up from sleep).
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

How does the reticular formation influence vital centres?

A
  • Cardiovascular and respiratory centres are located within the reticular formation.
  • Via the hypothalamus and nuclei involved in autonomic outflow, stimulation of these centres can:

1 - Influence respiratory rhythm.

2 - Slow heart rate.

3 - Reduce systemic blood pressure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which structures in the brainstem are the ventral horn and dorsal horn of the spinal cord analogous to?

A
  • The motor fibres of the cranial nerves arise from neuronal cell bodies that lie deep within the brainstem. These motor nuclei are analogous to the ventral horn of the spinal cord.
  • The sensory fibres of the cranial nerves arise from neuronal cell bodies in the superficial brainstem. These sensory nuclei are analogous to the dorsal horn of the spinal cord.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

List the cranial nerves that are involved in special sensory input.

A

Cranial nerves 1, 2 and 8.

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

List the cranial nerves that are involved in the control of eye movement and pupillary constriction.

A

Cranial nerves 3, 4 and 6.

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

List the cranial nerves that are involved in motor output only.

A

Cranial nerves 11 and 12.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

List the cranial nerves that are involved in mixed motor and sensory functions.

A

Cranial nerves 5, 7, 9 and 10.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

List the cranial nerves that have parasympathetic functions.

A

Cranial nerves 3, 7, 9 and 10.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Which cranial nerves are distributed entirely in the head and neck?

A

All but the vagus nerve.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Which cranial nerves have nuclei in the brainstem?

A

All but the olfactory and optic nuclei.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

List the cranial nerves.

A

1 - Olfactory.

2 - Optic.

3 - Oculomotor.

4 - Trochlear.

5 - Trigeminal.

  • Ophthalmic.
  • Maxillary.
  • Mandibular.

6 - Abducens.

7 - Facial nerve.

8 - Vestibulocochlear nerve.

9 - Glossopharyngeal.

10 - Vagus.

11 - Accessory.

12 - Hypoglossal.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

List the types of nerve fibres that convey information between the brainstem and the functional components of the cranial nerves.

A

Afferents:

1 - Special somatic afferents (SSA).

2 - General somatic afferents (GSA).

3 - Special visceral afferents (SVA).

4 - General visceral afferents (GVA).

Efferents:

5 - General somatic efferents (GSE).

6 - Special visceral efferents (SVE).

7 - General visceral efferents (GVE).

*Some of these fibres are also present in spinal nerves.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the function of special somatic afferents?

A

To transmit special senses such as sight, hearing and balance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the function of general somatic afferents?

A
  • To transmit sensation from the skin and mucous membranes.

- Sensations involved include pain, temperature, touch and proprioception.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the function of special visceral afferents?

A

To transmit information relating to taste.

34
Q

What is the function of general visceral afferents?

A

To transmit sensation from the digestive tract, heart, lungs and hollow organs.

35
Q

What is the function of general somatic efferents?

A

To transmit signals to skeletal muscles.

36
Q

What is the function of special visceral efferents?

A
  • To transmit signals to muscles derived from the pharyngeal arches of the embryo.
  • Despite innervating skeletal muscle, they are called visceral because of their function in fish.
37
Q

What is the function of general visceral efferents?

A

These efferents are the preganglionic fibres of the autonomic nervous system.

38
Q

To which area of the CNS do the cell processes of the sensory cranial nerves in the brainstem project?

Via which tract do they travel to this area?

Where do the neurones with which they synapse in this area then pass to?

A
  • The thalamus.
  • Via the trigeminothalamic tract.
  • The neurones that they synapse with in the thalamus then pass to the primary sensory cortex of the postcentral gyrus.
39
Q

From which area of the CNS do motor nuclei of cranial nerves receive impulses via upper motoneurones?

Via which tract do upper motoneurones travel from this area?

A
  • Primarily the primary motor cortex of the precentral gyrus, but also partially the primary sensory cortex of the postcentral gyrus.
  • Via the corticonuclear and corticobulbar tracts.
40
Q

List the fibre type(s) used by the olfactory nerve.

A

SVA.

41
Q

List the fibre type(s) used by the optic nerve.

A

SSA.

42
Q

List the fibre type(s) used by the oculomotor nerve.

A

1 - GSE.

2 - GVE.

43
Q

List the fibre type(s) used by the trochlear nerve.

A

GSE.

44
Q

List the fibre type(s) used by the trigeminal nerve.

A
  • V1: GSA.
  • V2: GSA.
  • V3: GSA + GSE.
45
Q

List the fibre type(s) used by the abducens nerve.

A

GSE.

46
Q

List the fibre type(s) used by the facial nerve.

A

1 - SVA.

2 - GSA.

3 - GVE.

4 - GVE.

47
Q

List the fibre type(s) used by the vestibulocochlear nerve.

A

SSA.

48
Q

List the fibre type(s) used by the glossopharyngeal nerve.

A

All general fibre types + SVA:

1 - GVA.

2 - GSA.

3 - SVA.

4 - GSE.

5 - GVE.

49
Q

List the fibre type(s) used by the vagus nerve.

A

All general fibre types + SVA:

1 - GVA.

2 - GSA.

3 - SVA.

4 - GSE.

5 - GVE.

50
Q

List the fibre type(s) used by the accessory nerve.

A

GSE.

51
Q

List the fibre type(s) used by the hypoglossal nerve.

A

GSE.

52
Q

Describe the general arrangement of nerve fibre types in the spinal cord.

A
  • General somatic efferents are found on the ventral side of the ventral horn.
  • General visceral efferents are found on the medial side of the ventral horn.
  • General somatic afferents are found on the dorsal side of the dorsal horn.
  • General visceral afferents are found on the medial side of the dorsal horn.
53
Q

List the fibre type(s) used by cervical spinal nerves.

A

1 - GSA.

2 - GSE.

54
Q

List the fibre type(s) used by thoracic spinal nerves.

A

All general fibre types:

1 - GSA.

2 - GVA.

3 - GSE.

4 - GVE.

55
Q

List the fibre type(s) used by lumbar and sacral spinal nerves.

A

All general fibre types:

1 - GSA.

2 - GVA.

3 - GSE.

4 - GVE.

56
Q

List the fibre type(s) used by coccygeal spinal nerves.

A

1 - GSA.

2 - GSE.

57
Q

List the muscles of the eye.

List the action of each muscle.

List the nerves supplying each muscle.

A

1 - Superior oblique (medially downwards, CN IV).

2 - Inferior oblique (medially upwards, inferior branch of CN III).

3 - Superior rectus (laterally upwards, superior branch of CN III).

4 - Inferior rectus (laterally downwards, inferior branch of CN III).

5 - Lateral rectus (laterally, CN VI).

6 - Medial rectus (medially, inferior branch of CN III).

58
Q

What are the terms for the movement of the eye upward, downward, laterally and medially?

A
  • Looking upwards is elevation.
  • Looking downwards is depression.
  • Looking medially is adduction.
  • Looking laterally is abduction.
59
Q

How do cranial nerve III, IV and VI coordinate to ensure a convergent gaze of the eyes?

A
  • Cranial nerves III, IV and VI communicate through the medial longitudinal fasciculus.
  • The medial longitudinal fasciculus contains brainstem gaze centres that coordinate eye movement.
  • Brainstem gaze centres are stimulated by cortical eye fields, which are regions of the frontal cortex.
  • The vestibular system also interacts with the eyes to coordinate eye movements with head movements using CN VIII and the cerebellum.
60
Q

Describe the area of the nerve territories of the trigeminal nerve branches.

A
  • The ophthalmic nerve covers the forehead, upper half of the eyes and frontonasal prominence.
  • The maxillary nerve covers the lower half of the eyes, the upper half of the cheeks, lateral nasal processes and upper lip.
  • The mandibular nerve covers the lateral sides of the face, lower half of the cheeks, chin and lower lip.
61
Q

What is supplied by the motor division of the trigeminal nerve?

A

Muscles of mastication.

62
Q

Describe the course of the facial nerve from its origin to the facial canal.

A

1 - Both roots of the facial nerve leave the brainstem to enter to temporal bone via the internal auditory meatus.

2 - Here, they accompany the vestibulocochlear nerve passing through the internal auditory canal.

3 - They then enter the facial canal, through which they continue to the periphery.

63
Q

List the segments of the facial canal.

A

1 - The labyrinthine segment.

2 - The external genu of CNVII.

3 - The tympanic segment.

4 - The mastoid segment.

64
Q

Through which opening does the facial nerve exit the facial canal?

A

The stylomastoid foramen.

65
Q

Describe the course of the facial nerve after it exits the facial canal.

A
  • It gives rise to several motor branches (whilst maintaining the main motor trunk) which collectively innervate 4 muscles:

1 - Posterior auricular.

2 - Occipital.

3 - Digastric.

4 - Stylohyoid.

66
Q

Describe the course of the main motor trunk of the facial nerve.

What branches does the facial nerve give?

A
  • It passes through the parotid gland.
  • Here, it terminates as 5 branches:

1 - Temporal.

2 - Zygomatic.

3 - Buccal.

4 - Mandibular.

5 - Cervical.

67
Q

Which area of the head receives motor innervation from the temporal and zygomatic branches of the facial nerve?

A

The upper face.

68
Q

Which area of the head receives motor innervation from the buccal, mandibular and cervical branches of the facial nerve?

A

The lower face and neck.

69
Q

How is the facial nerve tested?

Give the name of the muscles involved.

A

Test for ipsilateral paralysis of the:

1 - Eyelids (orbicularis oculi).

2 - Muscles that wrinkle the forehead (frontalis).

3 - Muscles involved in smiling.

70
Q

How is an upper motoneurone problem distinguished from a lower motoneurone problem with facial nerve damage?

A
  • Patients with upper motoneurone paralysis have lower facial weakness with an asymmetric smile.
  • Patients with lower motoneurone paralysis have weakness of all musculature innervated by CN VII.
71
Q

List 2 causes of a facial nerve lesion.

A

1 - Lyme disease.

2 - Varicella zoster virus.

72
Q

Describe the motor and sensory innervation of the glossopharyngeal nerve to the head and neck.

What is the function of the muscles that receive the motor innervation?

A

Motor:

1 - Stylopharyngeus.

2 - Superior pharyngeal constrictors.

  • They are muscles involved in swallowing.

Sensory:

1 - The upper pharynx.

2 - The posterior 1/3 of the tongue.

3 - Bitter and sour taste sensation from the posterior 1/3 of the tongue.

73
Q

Describe the motor and sensory innervation of the vagus nerve to the head and neck.

Via which branches of the vagus is this innervation conveyed?

A
  • Motor innervation is to muscles of the larynx.
  • Sensory innervation is to the pharynx and larynx.
  • Via the superior and recurrent laryngeal nerves.
74
Q

Describe the motor innervation of the accessory nerve to the head and neck.

What sensory innervation does the accessory nerve have?

A

Motor:

1 - Sternocleidomastoid.

2 - Trapezius.

  • The accessory nerve does not have any significant sensory innervation.
75
Q

List the nerve branches involved in the jaw jerk reflex.

What action should be seen with the jaw jerk reflex?

A
  • Afferent: Trigeminal (mandibular).
  • Efferent: Trigeminal (mandibular).
  • Action: The masseters should jerk the jaw upwards. Normally, the reflex is slight. With upper motoneurone lesions, the reflex is exaggerated.
76
Q

List the nerve branches involved in the corneal / blink reflex.

What actions should be seen with the corneal / blink reflex?

A
  • Afferent: Trigeminal (ophthalmic).
  • Efferent: Facial (temporal and zygomatic).

Action: Touching the cornea should elicit both a direct and consensual (opposite side) response to close the eyelid.

77
Q

What is the tentorial arch / notch?

A

An oval opening that is bounded by the sphenoid bone and tentorium cerebelli.

78
Q

Which component of the brainstem passes through the tentorial arch / notch?

A

The midbrain.

79
Q

What might cause compression of the brainstem at the tentorial arch / notch?

List 2 symptoms that might arise from brainstem compression.

A
  • Herniation due to infection following a dural tear.

1 - Loss of consciousness.

2 - Amnesia.

80
Q

Describe the organisation of branches of the laryngeal branches of the vagus nerve.

Are these branches motor, sensory or mixed?

A
  • The vagus gives rise to the recurrent and superior laryngeal nerves.
  • The recurrent laryngeal nerve is mixed.
  • The superior laryngeal nerve gives rise to external and interior branches.
  • The external branch is motor.
  • The internal branch is sensory.
  • The recurrent laryngeal nerve provides sensory innervation below the vocal cords and the internal branch of the superior laryngeal nerve provides sensory innervation above the vocal cords.
81
Q

List the nerves involved in the swallowing reflex.

Which nerves are afferent and which are efferent?

A
  • Afferent: Glossopharyngeal.

- Efferent: Vagus.

BAB (34 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions