Cranial Nerves & Reflexes Flashcards
Are Efferent fibers:
Motor or Sensory?
Motor
Are Afferent fibers:
Motor or Sensory?
Sensory
How many pairs of cranial nerves are there?
12 pairs
All cranial nerves distribute to the head and neck except 1…which 1?
CN X: Vagus
Goes to thorax and abdomen
Which cranial nerves are pure sensory and carry special senses?
1, 2, 8
- CN I: Olfactory
- CN II: Optic
- CN VIII: Vestibulocochlear
**smell, vision, hearing and equilibrium**
Which cranial nerves are pure motor and control extraocular eye movements?
3, 4, 6
- CN III: Oculomotor
- CN IV: Trochlear
- CN VI: Abducens
Which cranial nerves are pure motor and innervate the SCMs, traps and tongue?
11 & 12
- CN XI: Accessory
- CN XII: Hypoglossal
Which cranial nerves are MIXED sensory and motor?
5, 7, 9, 10
- CN V: Trigeminal
- CN VII: Facial
- CN IX: Glossopharyngeal
- CN X: Vagus
What does CN I do?
CN I: Olfactory
Smell
(pure sensory)
What does CN II do?
CN II: Optic
Vision
(pure sensory)
What do CN II & III do?
Pupillary Reflexes
- CN II: Optic (sensory)
- CN III: Oculomotor (motor)
What do CN III, IV, & VI do?
Extraocular movements
- CN III: Oculomotor - turns eyes up, down, in
Elevates eye lid
- CN IV: Trochlear - turns adducted eye down
- CN VI: Abducens - turns eye out
What does CN V do?
Sensory: Face, cornea
Motor: Temporal and masseter muscles
- CN V: Trigeminal
What does CN VII do?
Facial Expression
- CN VII: Facial
What does CN VIII do?
Vestibular function
Test eye-head coordination, VOR
Cochlear function
- CN VIII: Vestibulocochlear
What do CN IX & X do?
Phonation (voice quality)
Swallowing
Palatal, pharynx control
Gag Reflex
- CN IX: Glossopharyngeal
- CN X: Vagus
What does CN XI do?
Trap and SCM muscle function
- CN XI: Accessory nerve
What does CN XII do?
Tongue movements
- CN XII: Hypoglossal
What is a dermatome?
specific segmental skin area innervated by sensory spinal axons
What is a myotome?
skeletal muscles innervated by motor axons in a given spinal root
In the cervical spine, do numbered roots exit above or below the corresponding vertebral body?
Above
(C8 nerve root exits below C7 vertebral body)
In the thoracic, lumbar and sacral spine, do numbered roots exit above or below the corresponding vertebral body?
Below
At what level does the spinal cord end?
L1
What are the nerve roots called in the lumbosacral region?
Cauda Equina