Exam 1: Nervous System Brain and Cranial Nerves

Question 1

When does brain vesicle formation begin? (Primary vesicles)

Answer 1

3rd to 4th week of development

Question 2

what are the primary vesicles

Answer 2

prosencephalon (forebrain)
mesencephalon (midbrain)
rhombencephalon (hindbrain)

Question 3

when do secondary vesicles form? and what primary vesicles further develop into secondary vesicles?

Answer 3

• in the 5th week of development

- prosencephalon and rhombencephalon further develop

Question 4

secondary vesicles for prosencephalon

Answer 4

telencephalon (cerebrum) and diencephalon (extensions for eyes coming out, thalamus with levels of alertness, hypothalamus for coordination and BP HR and the eipthalamus with pineal gland for circadian rhythms)

Question 5

secondary vesicles of rhombencephalaon

Answer 5

metencephalon and myelencephalon

• metencephalon (pons and cerebellum)
• myelencephalon (medulla oblongata)

Question 6

what brain structure has 50% of neurons

Answer 6

cerebellum

Question 7

what are the 2 flexures shown in the 4th week (primary vesicles still)

Answer 7

cephalic

cervical

Question 8

what do the flexures initiate

Answer 8

boundaries of brain regions

Question 9

cephalic flexure

Answer 9

inferiorly marks boundary between mesencephalon and rhombencephalon (midbrain and the hindbrain)

superiorly marks boundary between prosencephalon and mesencephalon (forebrain and midbrain)

Question 10

cervical flexure

Answer 10

boundary between spinal cord and the rhombencephalon (hindbrain)

Question 11

flexure shown in the 5th week

Answer 11

pontine flexure

- boundary between myelencephalon and metencephalon of the rhombencephalon

Question 12

in the prosencephalon, the most anterior region forms two ____ which will develop into the _____

this differentiates the ___ from the ____

Answer 12

outpockets
cerebral hemispheres
telencephalon from the diencephalon

Question 13

polymicrogyria

Answer 13

abnormal development of gyri and sulci in the cerebrum
many small folds that can fuse together and prevent blood vessels from getting through

• regions of corpus callosum may not develop effecting speech, movement, seizures
• mainly in lateral fissure

causes: zika, cytomegalovirus, genetic deletions

Question 14

components of brainstem

Answer 14

medulla, pons, midbrain

the mesencephalon (midbrain) and the rhombencephalon (medulla and pons)

Question 15

brain stem function

Answer 15

autonomic reflex center

• involved in basic respiratory, cardiovascular and digestive functions
• picks up info to send to thalamus for level of alertness

Question 16

rhombencephalon components and their components

Answer 16

myelencephalon: medulla oblongata
metaencephalon: pons and cerebellum

Question 17

2 divisions of the medulla oblongata

Answer 17

autonomic centers and relay centers

Question 18

autonomic centers of medulla

Answer 18

mostly for visceral reflexes info

visceral sensory and visceral motor

Question 19

relay stations of medulla

Answer 19

SOMATIC
nucleus cuneatus
nucleus gracilis
olivary nucleus

Question 20

olivary nuclei of medulla

Answer 20

• each have many nuclei
• inferior: stays in medulla - motor communication with cerebellum

-Superior: crosses into pons - sound localization, relay from midbrain to cerebellum
inferior colliculus , involuntary saccades

Question 21

nucleus cuneatus

Answer 21

sends info from cuneatus tract to somatosensory center in cerebrum through thalamus
above T6

Question 22

nucleus gracilis

Answer 22

below T6

sends info from gracilis tract to somatosensory center in cerebrum through thalamus

Question 23

autonomic centers of the medulla

Answer 23

solitary nucleus
reticular formation
cardiovascular and respiratory centers

Question 24

receives and coordinates input from organ systems and cranial nerves 7,9,10
involved in gustatory, GI, chemoreceptor input and connections with cardiovascular and respiratory

Answer 24

solitary nucleus

Question 25

descends from RAS - helps with alertness | integrates with corticobulbar and solitary reflexes

Answer 25

reticular formation

Question 26

contain both accelerator and inhibitory regions gives basic mechanics of respiration and HR does not physically accelerate r decelerate

Answer 26

cardiovascular and respiratory centers

Question 27

2 functions of pons

Answer 27

contains autonomic centers | acts as bridge to and from cerebellum

Question 28

autonomic centers of pons

Answer 28

respiratory centers and peduncles

Question 29

2 respiratory centers of pons and what they do

Answer 29

pneumotaxic: controls respiration rate apneustic: controls depths of breaths - controls pneumotaxic - can inhibit rate of breathing, cannot accelerate it - like a brake in car going down hill you just remove brake and it goes on its own - slows down respiration - slow shallow breaths

Question 30

what happens if you destroy apneustic portion of respiratory center of pons?

Answer 30

respiration rate would increase, breathe faster, shallow breathes without control - gives tidal volume and hyperventilation

Question 31

peduncles and the three pairs in the pons

Answer 31

communication tracts to and from cerebellum superior, middle, inferior

Question 32

sends info regarding the current position of the body to the cerebellum proprioception - tension in muscles and joints unconsciously - spinocerebellar tracts, vestibular tracts

Answer 32

inferior peduncle

Question 33

allows reception of corticospinal info determines intended movement monitor info and take to cerebellum

Answer 33

middle peduncle

Question 34

connects to cerebrum sends efferent info from cerebellum to midbrain and thalamus fine tune it and send to midbrain suggestion on how to do it better

Answer 34

superior peduncle

Question 35

cerebellum

Answer 35

has reversed organization: white matter (arbor vitae) on inside 50% of neurons in brain involved in: postural reflexes, voluntary muscle movement coordination, timing, procedural memory

Question 36

lobes of the cerebellum

Answer 36

vermis flocculonodular anterior and posterior lateral hemispheres

Question 37

vermis

Answer 37

runs down middle | spinocerebellar integration - proprioception

Question 38

flocculonodular

Answer 38

vestibulocular reflexes - unconscious saccades as you move you do not have to think about adjusting where you are at ex: spinning people in barany test - nystagmus at end

Question 39

anterior and posterior lateral hemispheres

Answer 39

planning, timing, cognitive function | figuring out how to do an action more smooth

Question 40

layers of the cerebellum

Answer 40

molecular layer purkinje layer granule layer

Question 41

fine tuning integration layer of the cerebellum

Answer 41

molecular layer

Question 42

layer of cerebellum with LARGE cells, only ones that sends signals to the deep cerebellar nucleus coordination, smooth movement of muscle

Answer 42

purkinje layer

Question 43

layer of cerebellum with densely populated glial cells and feedback cells

Answer 43

granule layer

Question 44

main fibers of cerebellum circuitry

Answer 44

climbing, mossy, purkinje

Question 45

modifiers of cerebellum circuitry

Answer 45

granules, golgi, basket/stellate

Question 46

climbing fibers

Answer 46

current position of the body | tension in joints and muscles

Question 47

mossy fibers

Answer 47

some input regarding proprioception, carries input for intended movement monitor from spinocerebellar - what is motor cortex sending out

Question 48

purkinje fibers

Answer 48

send out final cue to dentate- dentate nuclei initially stimulated by mossy on their way in

Question 49

granule modifiers

Answer 49

put out parallel fibers to communicate info from mossy fibers to many purkinje cells increased granule = increased purkinje output

Question 50

golgi modifiers

Answer 50

monitor parallel fibers and mossy input negative feedback loop with granules increased golgi = decreased purkinje output

Question 51

basket/stellate

Answer 51

monitor parallel fibers | inhibit purkinje output

Question 52

what modifiers decrease purkinje output

Answer 52

golgi, basket, stellate

Question 53

dentate nuclei

Answer 53

have 4 pairs of nuclei send feedback to motor cortex, thalamus, and basal ganglia dorsal: voluntary, skeletal ventral: visual spatial - conscious

Question 54

functions of the midbrain (mesencephalon)

Answer 54

- relays info for vision and hearing | - role in head and neck movement - speech motor movements

Question 55

2 paired structures in corpora quadrigemina in midbrain

Answer 55

``` superior colliculi (visual reflexes) inferior colliculi (auditory reflexes) CN 2,3,4,8 involved ```

Question 56

3 relays of the midbrain

Answer 56

medal lemniscus corticospinal reticular formation

Question 57

medial lemniscus

Answer 57

dosal columns going up

Question 58

corticospinal

Answer 58

descending tracts, communicate with cerebellum

Question 59

reticular formation

Answer 59

continuous from lower brain stem to thalamus involved in alertness pain perception - of senses just NOT smell movement control

Question 60

highly vascular important in extrapyramidal tracts\adjustments in movement relayed through here posture and head, neck, upper body movement russian 15yr old olympics- risk of impairments to extrapyramidal tracts - reflexive, rigidity in postural reflexes

Answer 60

red nucleus

Question 61

``` dense with dopaminergic cells dark color-metabolized dopamine regulates GABA producing cells for fine tuning voluntary motor movement when to start and stop movement links to limbic system and basal ganglia ```

Answer 61

substantia nigra

Question 62

components of prosencephalon

Answer 62

diencephalon and telencephalon

Question 63

diencephalon

Answer 63

- relays all sensory info besides smell - controls many autonomic functions(raise or lower T, HR - integration with endocrine system (pituitary gland) - hypothalamus

Question 64

telencephalon

Answer 64

- largest division in brain - memory processing - complex learned behavior - cognitive functions - how you process and make memories, judgement - somatic regulation