Reticular Formation and Cerebellum (3) Flashcards Preview

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Flashcards in Reticular Formation and Cerebellum (3) Deck (82):
1

the reticular formation is the central core of the brainstem and extends into the cerebrum as the _____

hypothalamus

2

From medial to lateral what are the 3 longitudinal zones of the RF ?

R and L Median zone - Raphe
Medial Zone - Paramedian
lateral zone (largestt) Zone

3

what zone of the RF houses most of the ascending and descending neural tract projections

Medial or paramedian zone

4

what part of the brainstem would you find the lateral zone of the RF

rostral medulla and caudal pons

5

what zone of the RF is involved with cranial nerve reflexes and visceral functions

Lateral zone

6

what are the 2 reticulospinal tracts of the RF, and where could they be found in the brainstem

-medial reticulospinal tract - pons
-lateral reticulospinal tract - medulla

7

The RF and its reticulospinal tracts are involved with what functions

-regulate spinal motor neurons
-influence spinal motor neurons directly
-regulate spinal reflexes

8

the reticulospinal tract neurons of the RF recieve input from where ?

cerebral cortex
basal ganglia
substantia nigra ... (multiple locations)

9

the RF is known to be a "pattern generator", what does this mean

Controls/coordinates rhythmic motor patterns
-gaze centers (midbrain and pons)
-mastication (pons)
-locomotion (pons)
-medulla vital center

10

the RF is involved with controlling rhythmic motor patterns, and one area of control is the Medulla "vital center" which controls what ?

-respiration
-heart rate
-swallowing/vomiting

11

what is bruxism and what are the theories for what causes this ?

tooth grinding cuz jaw muscles are co-contracted at night
-Peripheral theory - jaw muscles constantly trying to reach occlusion
-Central theory - sleep related neural dysfunction

12

what role can the RF play in pain pathways

Suppress or facilitate pain (wounded soldiers keep fighting)

13

where is the central location that is involved with RF pain supress system

periaqueductal grey (PAG)

14

what zone of the RF would fibers carrying pain infortmation be found ?

Raphe (nucleus magnus) -----> then to posterior horn of spinal cord

15

where would you find opiate receptors in the RF

-PAG
-raphe
-posterior horn of spinal cord

16

What is the RF role in autonomic reflex circuitry

controls visceral information and responds accordingly to environmental changes
(similar to pattern generators in motor control)

17

what part of the brainstem is involved with the RF involvment in arousal

midbrain and pons
-sends info to thalamus then cortex and heightens arousal

18

the RF control of maintaining consciousness is better known as what system

Ascending reticular activating system (ARAS)

19

damage to what part of the brainstem could result in prolonged coma

bilateral damage to midbrain would damage ARAS of RF

20

T/F ARAS has a role in the sleep-wake cycles

True

21

what nuerochemicals involved with the RF are produced in the brainstem

norepinephrine (NE)
dopamine (DA)
serotonin

22

what neurochemicals involved with the RF are produced in the hypothalamus

histamine containing neurons

23

what neurochemical partly involved with the RF is produced in the telencephalon

acetylcholine

24

norepinephrine is made by _______ neurons which are located where ?

noradrenergic neurons
-Rostral pons (locus ceruleus) ***
-medulla (solitary nucleus)

25

sensory info that stimulates the locus ceruleus neurons cause what ?

production of NE (increase arousal and anticipation)
-releases into cortex, trigeminal spinal nucleus, spinal cord

26

reduced locus ceruleus activity (reduced levels of NE) causes what

clinical depression

27

increased activity of the locus ceruleus (increase NE) could cause

panic disorder

28

dopamine is produced by ________ neurons located where

dopaminergic neurons in the midbrain
-substantia nigra
-ventral tegmental area

29

what tract degenerates in people with parkinsons disease

nigrostriatal tract (substantia nigra to striatum)
-involved with motor activity from DA

30

what are the components of the striatum and what neurochemical has projections through here

caudate and putamen
-dopaminergic projections

31

what is the major source of DA

Ventral tegmental area

32

what are the 2 tracts of the Ventral Tegmental Area

Mesolimbic tract - to limbic system
Mesocortical tract - to frontal cortex

33

what is implicated in schizophrenia ?

the 2 tracts of the ventral tegmental area

34

what are two components of schizophrenia and what is the cause of each

Social withdrawal - low DA levels in prefrontal cortex
Hallucinations - high DA levels in limbic system

35

serotonin is produced by serotonergic neurons which are located where ?

all brainstem levels in raphe of RF

36

serotonergic neurons in the midbrain raphe nuclei project to the ______ and are involved with what ?

Cortex
-Focusing/paying attention
-hypothalamus day/night cycle

37

sertonergic neurons in the medullary raphe nuclei project to the _______ and are involved with ?

spinal cord
-pain supression (nucleus raphe magnus)

38

Selective Serotonin Reuptake Inhibitors (SSRI) are used to treat ?

Clinical depression

39

Low levels of serotonin would result in ?

Binge eating
high carb consumption (women)

40

high levels of serotonin would result in

complulsive behavior
annorexia nervosa

41

drugs that increase levels of serotonin are used to treat

anxiety and depression

42

Achetylcholine is produced by _____ neurons and are produced where at in the RF

cholinergic
-dorsolateral pontine tegmentum

43

Acetylcholine is largely produced outside of the RF (meaning its just a lil part of RF). Where are these produced

basal nucleus (of Meynert) of basal forebrain

44

what are the main functions of the cerebellum

-regulate equilibrium
-regulate muscle tone/posture
-motor coordination for voluntary movements in the future (plans) and during execution

45

the surface of the cortex of the cerebellum is composed of _____ matter whereas the _____ matter is inside

grey, white

46

what are the 2 main fissures of the cerebellum and what lobes do they seperate

primary fissure - anterior from posterior lobe
posterolateral fissure - floculonodular lobe from posterior lobe

47

what is the midline of the cerebellum called

vermis

48

what are the 3 lobes of the cerebellum

anterior
posterior
floculonodular

49

what are the 3 cerebellar peducncles

inferior cerebellar peduncle (Restiform body)
middle cerebellar peduncle (brachial pontis) - largest
superior cerebellar peduncle

50

where does the inferior cerebellar peduncle recieve input from, and what is its function

spinal cord and brain stem
-monitor muscle and limb movement

51

what is the function of the middle cerebellar peduncle

"IN Pathway"
-recieves afferents from basis pontis and relays motor signals from cortex

52

what is the function of the superior cerebellar peduncle

"out pathway"
-sends efferents to red nucleus and thalamus

53

what are the 4 cerebellar deep nuclei

dentate nuclei
interposed nucleus - emboliform and globose
fastigal nuclei

54

what is the broad overview of the cerebellar circuitry

-inputs to ICP and MCP (most)
-send to cortex
- cortex send to deep nuclei
-deep nuclei send outputs via SCP

55

what are the 3 structural layers of the cerebellar cortex

-Molecular layer (top)
-Perkinjie cell layer
-Granule layer

56

what structural layer of the cerebellar cortex has axons that projects outputs

Perkinjie layer

57

what are the 3 fibers in basic cortical (cerebellar cortex) activity

-climbing fibers
-mossy fibers
-parallel fibers

58

what do climbing fibers do

major cortical (cerebellar cortex) input from contralateral inferior olivary nucleus

59

what do mossy fibers do ?

major cortical (cerebellar cotex) input from brainstem, vestibular system, and spinal cord

60

where do climbing fibers synapse

on purkinje cels which regulates purkinje cell firing

61

where do mossy fibers synapse

synapse on granule cells

62

what connects the cerebellar cortex to deep nuclei

-collaterals from climbing and mossy fibers
-purkinje axons end on deep nuclei

63

what are the 2 neuronal populations w/in the deep nuclei of the cerebellar cortex

-mossy fibers into cerebellar cortex
-output neurons leaving cerebellum

64

what are the 3 functional subdivisions or longitudinal zones of the cerebllum from medial to lateral

1 - vestibulocerebellum
2 - spinocerebellum
3 - pontocerebellum

65

the vestibulocerebellum is made up of what structural parts of the cerebellum

floculonodular lobe and part of vermis

66

the spinocerebellum is made up of what structural parts of the cerebellum

paravermal area (medial hemisphere) and part of vermis

67

the pontocerebellum is made up of what structural parts of the cerebellum

lateral hemisphere

68

what is the input, output, and function of the vestibulocerebellum

input - vestibular organ/nuclei
output - fastigal deep nuclei
function - balance, control eye during head movements

69

what is the input, output, and function of the spinocerebellum

input - brainstem and spinal cord
output - interposed deep nuclei (emboliform and globose)
function - coordinate trunk/limb movements

70

what is the input, output, and function of the pontocerebellum

input - basilar pons and MCP (motor cortex)
output - dentate deep nuclei
function - planning timing movements (upper arm) and coordinate speech

71

once the spinocerebellum recieves inputs at the interposed nuclei, where does it relay the message to ?

Red nucleus -----> VA/VL of thalamus ---> limb area of primary motor cortex

72

once the pontocerebellum recieves inputs at the denate nucleus, where does it relay the message to ?

red nucleus ---> VA/VL of thalamus ----> all motor cortex and parietal lobe

73

what is the function of the lateral hemisphere of the cerebellum

planned timing/skillful movements that get better w/practice

74

what is the function of the medial hemisphere of the cerebellum

adjusting/coordinating limb movements

75

what is the function of the vermis

postural adjustments (balance)

76

what deep nuclei does the vermis project to ?

fastigal

77

what deep nuclei does the medial hemisphere project to

interposed nuclei (emboliform and globose)

78

what deep nuclei does the lateral hemisphere project to

dentate

79

the principal OUTPUT from cerebellar nuclei is via

SCP

80

The left side of the cerebellum projects to _______ side of the thalamus

right (contralateral )

81

Left half of the cerebellum influences ______ limbs

Left (ipsilateral)

82

Right cerebral hemisphere controls ______ muscles

Left (contralateral)