Trigeminal Proprioception Flashcards Preview

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Flashcards in Trigeminal Proprioception Deck (35)
1

what is proprioception

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

2

what is kinaesthesia

movement awareness

3

what are the receptors involved in proprioception

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

4

what does principal jaw closing muscles have

muscle spindles

5

do jaw open muscles have muscle spindles

no

6

what is designed to put force through teeth

jaw closing muscles
PDL mechanoreceptors

7

what is special about the TMJ

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

8

what do inner ear receptors contribute

perceive head position

9

what are the two types of muscle fibres

extrafusla and intrafusal

10

what are extrafusal fibres

bulk of muscle fibres
contractile
generate force and movement

11

what are intrafusal fibres

muscle spindles
specialised muscle fibres
within a ct capsule

12

what are the there zones of an intrafusla fibre

2 contractile end portions
non contractile central portion can be stretched

13

what are the afferents of the intrafusal fibre activated by

stretch

14

what are the secondary nerve endings in the intrafusal fibre

detects length of fibres slowly adapting

15

what is the primary annulo-spira nerve endings

detects length of fibres and speed of change of length

16

what is the efferent in intrafusal fibres

gamma motor neurone
ake contraction

17

what fibres supply the extrafusal fibres

alpha motor neurones

18

what is significant about alpha motor neurones

fastest afferents in the body

19

how can you record muscle spindle activity

oscilloscope

20

what is seen by a muscle fibre at rest

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

21

what happens to muscle fibres firing when stretched

the more stretched the more firing

22

what are the main roles of muscle spindle fibres

info about muscle length
act to maintain muscle length

23

what is the thought process behind jerk reflexes

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

24

what is an example of muscle spindles in action

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

25

where are masticatory muscle spindles

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

26

where do muscle spindle afferents synapse for masticatory muscles

v motor nucleus
and cerebellum and cerebral cortex

27

what happens when muscle shortens

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

28

what do gamma motor neurones do

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

29

what is another muscle spindle role and what is analogy

load compensation
-- carrot analogy

30

what are golgi tendon organs

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

31

what are the joint receptors

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

32

what is interdental detection

can detect 50 microns between teeth

33

what are the receptors for interdental detection

PDLM's
muscle spindles
maybe joint receptors

34

what si the jaw repining test

ability to reposition jaw
accuracy of order <2mm

35

what are the receptors for jaw repositioning test

muscle spindles
TMJ
not PDLM's as no tooth contact