Brainstem

Question 1

How is the medulla (aka mylencephalon) organized

Answer 1

Same general organization as spinal cord (top - sensory; bottom - motor); reticular formation (reticular activating system; states of arousal), nuclei inside (olivary nuclei, etc)

Question 2

What are the three fields of the medulla

Answer 2

Median & paramedian (raphe nuclei), Medial 2/3 (part of tegmental field, magnocellular, big cells with disc shaped dendrites), Outer third (lateral tegemental field, parvocellular)

Question 3

What are the components of the metencephalon

Answer 3

pons, cerebellum, vestibular system (semicircular canals (fluid filled, angular accelerometers, , utricles and saccules (otocith organs; gravity detection) that goes to 4 vestibular nuclei complex (lateral, superior, inferior, medial) than that goes to chord/cerebellum/reticular formation/reticular nuclei…

Question 4

What are the components of the metencephalon

Answer 4

pons, cerebellum, vestibular system (semicircular canals (fluid filled, angular accelerometers, , utricles and saccules (otocith organs; gravity detection) that goes to 4 vestibular nuclei complex (lateral, superior, inferior, medial) than that goes to chord/cerebellum/reticular formation/reticular nuclei…

Question 5

Components of Mesencephalon

Answer 5

Midbrain: pretectum (occulomotor), tectum (superior/inferior colliculus), tegmentum (reticular nuclei), cerebral aquaduct, pariaqueductal gray (pain circuity), red nucleus, locus coeruleus, substantia nigra

Question 6

Describe the different categories of afferent/efferent in brainstem

Answer 6

General somatic afferent (from skeletal muscles, skin, joints, ligaments), general somatic efferent (to muscle), general visceral afferent (from organs and blood vessels), general visceral efferent (smooth muscle of organs, glands)

Question 7

Classify the fibers of the cranial nerves

Answer 7

special somatic afferent (retina, cochlea), special sommatic efferent (taste, smell), special visceral efferent (muscles in the back of throat)

Question 8

Among the cranial nerves which ones are involved in moving the eyes (somatic motor)

Answer 8

trochlear (smallest nerve, goes on top of eye, causes intorsion), occulo motor (largest of the three; PLR), abducens

Sidenote: the other somatic motor nerve is the hypoglossal nerve (tongue muscles)

Question 9

Cranial nerve involved in sensory info from face (temp, touch, vibrations) and mastication?

Answer 9

Trigeminal nerve (huge, three divisions). general sensory & branchial motor

Question 10

Where is norepinephrine foudn

Answer 10

dorsal medullary, lateral tegmental, LC (mesencephalon) -> locus coreulus

Question 11

what does spinal accessory nerve do

Answer 11

innervate mastoid, trapezius -> head movement

Question 12

vagus nerve function

Answer 12

sends down parasympathetic output of brain (digestion goes up, heart rates goes down)

Question 13

glossopharyngeal function

Answer 13

send sensory info from back of tongue and throat