Trigeminal Proprioception

Question 1

what is proprioception

Answer 1

awareness of position of body parts in relation to each other and surroundings

Question 2

what is kinaesthesia

Answer 2

movement awareness

Question 3

what are the receptors involved in proprioception

Answer 3

muscle spindles
golgi tendon organs
joint receptors
- also stretch receptors in skin

Question 4

what does principal jaw closing muscles have

Answer 4

muscle spindles

Question 5

do jaw open muscles have muscle spindles

Answer 5

no

Question 6

what is designed to put force through teeth

Answer 6

jaw closing muscles

PDL mechanoreceptors

Question 7

what is special about the TMJ

Answer 7

has range of receptors give information how open and how close and speed doing so of the jaw

Question 8

what do inner ear receptors contribute

Answer 8

perceive head position

Question 9

what are the two types of muscle fibres

Answer 9

extrafusla and intrafusal

Question 10

what are extrafusal fibres

Answer 10

bulk of muscle fibres
contractile
generate force and movement

Question 11

what are intrafusal fibres

Answer 11

muscle spindles
specialised muscle fibres
within a ct capsule

Question 12

what are the there zones of an intrafusla fibre

Answer 12

2 contractile end portions

non contractile central portion can be stretched

Question 13

what are the afferents of the intrafusal fibre activated by

Answer 13

stretch

Question 14

what are the secondary nerve endings in the intrafusal fibre

Answer 14

detects length of fibres slowly adapting

Question 15

what is the primary annulo-spira nerve endings

Answer 15

detects length of fibres and speed of change of length

Question 16

what is the efferent in intrafusal fibres

Answer 16

gamma motor neurone

ake contraction

Question 17

what fibres supply the extrafusal fibres

Answer 17

alpha motor neurones

Question 18

what is significant about alpha motor neurones

Answer 18

fastest afferents in the body

Question 19

how can you record muscle spindle activity

Answer 19

oscilloscope

Question 20

what is seen by a muscle fibre at rest

Answer 20

spindle afferent at rest see AP’s fire at set rate

Question 21

what happens to muscle fibres firing when stretched

Answer 21

the more stretched the more firing

Question 22

what are the main roles of muscle spindle fibres

Answer 22

info about muscle length

act to maintain muscle length

Question 23

what is the thought process behind jerk reflexes

Answer 23

muscle spindle afferents synapse with alpha motorneuorens increase stretch muscle increases firing which causes contraction
feedback loops synchronised muscle stretch

Question 24

what is an example of muscle spindles in action

Answer 24

bucket fills with water
biceps spindles stretch
increased moo neurone drive to biceps
muscle length maintained

Question 25

where are masticatory muscle spindles

Answer 25

in cell bodies in trigeiminla mesencehlaic nucleus in CNS don’t synapse here

Question 26

where do muscle spindle afferents synapse for masticatory muscles

Answer 26

v motor nucleus

and cerebellum and cerebral cortex

Question 27

what happens when muscle shortens

Answer 27

when shortens signal t alpha send a gamma also cause intrafusal to contract to keep it tense and therefore responsive

Question 28

what do gamma motor neurones do

Answer 28

contraction of intrafusal fibres
maintain tension in spinde
maintain spindle afferent activity
alpha-gamma co activation

Question 29

what is another muscle spindle role and what is analogy

Answer 29

load compensation

– carrot analogy

Question 30

what are golgi tendon organs

Answer 30

series with muscle fibres in tendons
non in mast muscles
tension receptors
role in inhibit reflex

Question 31

what are the joint receptors

Answer 31

pacinian - ligaments - acceleration
golgi - ligament - position
ruffini - capsule - movement

Question 32

what is interdental detection

Answer 32

can detect 50 microns between teeth

Question 33

what are the receptors for interdental detection

Answer 33

PDLM’s
muscle spindles
maybe joint receptors

Question 34

what si the jaw repining test

Answer 34

ability to reposition jaw

accuracy of order <2mm

Question 35

what are the receptors for jaw repositioning test

Answer 35

muscle spindles
TMJ
not PDLM’s as no tooth contact