Brainstem Nuclei and Tracts

Question 1

where is brainstem located

Answer 1

between cerebrum and spinal cord

Question 2

what does the brainstem consist of

Answer 2

midbrain, medulla and pons

Question 3

what is brainstem made of

Answer 3

deep grey matter surrounded by white matter tracts

Question 4

which pathway of the spinal cord is ascending

Answer 4

sensory

Question 5

what pathway of the spinal cord is decending

Answer 5

motor

Question 6

what does the midbrain develop from

Answer 6

mesencephalon

Question 7

what does the pons develop from

Answer 7

rhombencephalon

Question 8

what does the medulla oblongata develop from

Answer 8

rhombencephalon

Question 9

what does the spinal cord develop from

Answer 9

rhombencephalon

Question 10

what is the corticobulbar tract

Answer 10

a motor pathway that goes from the cortex to the brainstem

Question 11

what are the corticospinal tracts

Answer 11

motor pathways that travel along the spinal cord

Question 12

what does the lateral corticospinal tract do

Answer 12

conveys commands to the body (piano playing, tap dancing)

Question 13

what does the anterior corticospinal tract do

Answer 13

controls trunk muscles (core exercises)

Question 14

what is the optic chiasm

Answer 14

where optic nerves cross over

Question 15

what is the middle ceerebellar peduncle

Answer 15

connects pons to cerebellum

Question 16

what does the superior colliculis relate to

Answer 16

vision

Question 17

what does the inferior colliculus refer to

Answer 17

hearing

Question 18

which cranial nerves do not originate from the brain stem

Answer 18

I & II

Question 19

where does the occulomotor nerve (III) emerge from

Answer 19

interpenduncular fossa

Question 20

where does the trochlear nerve (IV) emerge from

Answer 20

posterior aspect of brainstem

Question 21

where does the trigeminal nerve (V) emerge from

Answer 21

anterolateral section of pons

Question 22

where does the abducens nerve (VI) emerge from

Answer 22

pontomedullary junction

Question 23

what is the pontomedullary juntion

Answer 23

part of pons where it meets medulla oblongata

Question 24

where does the facial nerve (VII) emerge from

Answer 24

pontomedullary junction

Question 25

where does the vestibulocochlear nerve (XIII) emerge from

Answer 25

pontomedullary junction

Question 26

where does the glossopharyngeal nerve (IX) emerge from

Answer 26

medulla oblongata

Question 27

where does the vagus nerve (X) emerge from

Answer 27

medulla oblongata

Question 28

where does the spinal accessory nerve (XI) emerge from

Answer 28

medulla oblongata

Question 29

where foes the hypoglossal nerve (XII) emerge from

Answer 29

medulla oblongata

Question 30

what does the ventral part of the midbrain relate to

Answer 30

motor

Question 31

what does the dorsal aspect of the midbrain relate to

Answer 31

sensory

Question 32

what separates the ventral and dorsal aspects of the midbrain

Answer 32

cerebral aqueduct

Question 33

what do the superior colliculi and inferior colliculi make up together

Answer 33

corpora quadrigemina

Question 34

what do the superior colliculi do

Answer 34

relay input from the optic tract to the lateral geniculate bodies of the thalamus

Question 35

what do the inferior colliculi do

Answer 35

send information to the medial geniculate bodies of the thalamus

Question 36

what is the reticular activating system

Answer 36

present throughout the brainstem and it is involved in sleep wake cycles

Question 37

three nuclei types of the midbrain

Answer 37

- red nuclei - nuclei of cranial nerves III & IV - substantia nigra

Question 38

what are the red nuclei

Answer 38

- contain numerous blood vessels - receive information from cerebellum and cerebrum - issues subconscious motor commands concerned with muscle tone and posture

Question 39

what is the substantia nigra

Answer 39

- lateral to the red nucleus - contains melanin - seceretes dopamine to inhibit the excitatory neurons of the basal nuclei

Question 40

what happens when there is degeneration of the substantia nigra

Answer 40

parkinsons

Question 41

what do the motor tracts of the midbrain do

Answer 41

- includes fibres of pyramidal system - pass downward on midbrain's ventral surface

Question 42

what do sensory axons in midbrain do

Answer 42

- include those from spinothalamic tract - ascend along dorsal midbrain

Question 43

what are the cerebral peduncles also called

Answer 43

crus cerebri

Question 44

what are the cerebral peduncles

Answer 44

efferent projections including corticobulbar and corticospinal axons

Question 45

what four cranial nerve nuclei are found in the pons

Answer 45

- trigeminal (V) - abducens (VI) - facial (VII) - vestibulocochlear (VIII)

Question 46

nuclei of pons | not cranial nerves

Answer 46

- apneustic and pneumotaxic centres work with medulla to maintain respiratory rhythm - raphe nuclei - reticular activating system

Question 47

tracts of the pons

Answer 47

- superior, middle and inferior cerebellar peduncles - motor and sensory tracts (sensory fibres are always posterior to motor fibres)

Question 48

what are the cerebellar peduncles

Answer 48

tracts that process and relay information to and from the cerebellum

Question 49

what are the nuclei of the medulla associated with

Answer 49

- autonomic control - cranial nerves - sensory/motor relays

Question 50

three types of nuclei present in medulla

Answer 50

- autonomic nuclei - sensory and motor of 5 cranial nerves - relay nuclei

Question 51

three types of autonomic nuclei | medulla

Answer 51

- cardiovascular centres - respiratory rhythmicity centres - additional centres

Question 52

what do cardiovascular centres do

Answer 52

- alter rate and force of contractions - alter tone of vascular smooth muscle

Question 53

what do respiratory rhythmicity centres do

Answer 53

recieve input from pons to control respiratory rhythm

Question 54

additional centre examples | medulla autonimic nuclei

Answer 54

- emesis - deglutition - coughing - hiccupping - sneezing

Question 55

what four cranial nerves have their nuclei in the medulla

Answer 55

- glossopharyngeal (IX) - vagus (X) - spinal accessory (XI) - hypoglossal (XII)

Question 56

what are the relay nuclei

Answer 56

- nucleaus gracilis and nucleus cuneatas pass somatic sensory information to thalamus - olivary nuclei relay information from spinal cord, cerebral cortex and brainstem to cerebellar cortx

Question 57

what tracts are present in the medulla

Answer 57

ventrally, 2 ridges (medullary pyramids) are visible these are formed by the large motor corticospinal tracts