01/21 Cranial Nerves Flashcards Preview

Neuroanatomy > 01/21 Cranial Nerves > Flashcards

Flashcards in 01/21 Cranial Nerves Deck (26)
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1
Q

What are the sensory-only cranial nerves?

A

CN I - olfactory
CN II - optic
CN VIII - vestibulocochlear/acoustovestibular

2
Q

What are the motor-only cranial nerves?

A

CN IV - abducens
CN VI - trochlear
CN XI - accessory spinal
CN XI - hypoglossal

3
Q

What are the sensory/motor cranial nerves?

A
CN III - oculomotor
CN V - trigeminal
CN VII - facial
CN IX - glossopharyngeal
CN X - vagus
4
Q

What are the functions of the oculomotor nerve?

A

Motor innervation to four eyeball muscles and levator palpebrae superioris
Parasympathetic innervation to the ciliary ganglion - contraction of the pupil

5
Q

What are two prominent clinical findings when a patient has a damaged oculomotor nerve?

A

Fixed and dilated pupil

Ptosis of the upper eyelid

6
Q

What are the functions of the trigeminal nerve?

A

Sensory innervation from the face, cornea, mouth, nose, and temporomandibular joint
Motor innervation to the muscles of mastication

7
Q

What are the functions of the facial nerve?

A

Sensory innervation from the anterior 2/3 of the tongue
Motor innervation to the muscles of facial expression
Parasympathetic innervation to sublingual, submandibular, and lacrimal glands

8
Q

What are the resulting symptoms of damage to the facial nerve?

A

Facial droop
Dry eyes
Dry mouth

9
Q

What are the functions of the glossopharyngeal nerve?

A

Sensory innervation from the posterior 1/3 of the tongue, auditory tube, and pharynx
Parasympathetic innervation to the parotid gland

10
Q

What are the functions of the vagus nerve?

A

Sensory innervation from the larynx and pharynx
Motor innervation to the larynx and pharynx
Parasympathetic innervation to organs of the chest and abdomen

11
Q

What are the functions of the outer and middle ear?

A

To collect and amplify sound waves

12
Q

What is the function of the hearing portion of the inner ear? What are its parts?

A

Transmits sound waves into mechanical movements and nerve impulses
Cochlea and hair cells

13
Q

Trace the path of the vestibulocochlear nerve to the auditory cortex

A

1) Vestibulocochlear nerve
2) Dorsal and ventral cochlear nuclei (in the medulla)
3) Inferior colliculus via the lateral lemniscus
4) Medial geniculate nucleus (in the thalamus)
5) Primary auditory cortex - superior temporal lobe (Brodmann areas 41 and 42)

14
Q

Axons from which visual field cross to the other side at the optic chiasm?

A

Temporal visual field

15
Q

Trace the path of the optic nerve from the eye to the primary visual cortex

A

1) Optic nerve
2) Optic chiasm
3) Optic tract
4) Lateral geniculate nucleus
5) Optic radiations
6) Primary visual cortex - calcarine fissure in occipital lobe (Brodmann area 17)

16
Q

What is the result of a lesion in one eye or one optic nerve?

A

Right or left anopsia (single-eye blindness)

17
Q

What is the result of a lesion to the optic chiasm?

A

Bitemporal hemianopsia (tunnel vision)

18
Q

What is the result of an injury to the optic tract, optic radiations, or optic visual cortex?

A

Homonymous hemianopsia (blindness in either the right or left visual field)

19
Q

Trace the path of the olfactory nerve starting from the sensory receptors in the nasal mucosa

A

1) Bipolar receptor neurons in nasal mucosa
2) Impulses sent via the olfactory bulb and tract
4) Anterior perforated substance
* Also connections with the entorhinal cortex, amygdala, hippocampus, fornix, and mammillary bodies

20
Q

What system is intimately related with the olfactory system?

A

Limbic system

21
Q

What functions are regulated by the hypothalamus?

A
Sleep
Body temperature
Water balance
Blood pressure
Hunger
Pituitary hormone secretion
Sympathetic and parasympathetic balance
22
Q

What are the functions of the descending reticular system?

A

Projects to autonomic nervous system (sympathetic and parasympathetic)
Relays extrapyramidal output to the voluntary muscles via the pontine tegmentum

23
Q

What are the functions of the ascending reticular activating system?

A

Provides input from all sensory organs to the thalamus and cortex
Important for arousal from sleep by stimuli

24
Q

Which cranial nerve nuclei are located in the midbrain?

A

Oculomotor (III)

Trochlear (IV)

25
Q

Which cranial nerve nuclei are located in the pons?

A

Trigeminal (V)
Abducens (VI)
Facial (VII)
Vestibulocochlear (VIII)

26
Q

Which cranial nerve nuclei are located in the medulla?

A

Glossopharyngeal (IX)
Vagus (X)
Spinal accessory (XI)
Hypoglossal (XII)