Flashcards in Mechanoreception No.1 Deck (43)
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31
what is 2 point discrimination tests
experiment ot see resolution touch diff parts of body
how close two blunts point can be to distinguish two points
32
what are the 2 point discrimination thresholds fro tip tongue and lips
low 2 point threshold
tip tongue 1mm
centre lip
high innervation density
small receptive field
33
what are the 2 point discrimination thresholds for fingertips
low 2 point thresholds
able to discriminate small objects
34
what are the PDLM's
periodontal ligament mechanorceep
imp sensory
exteroceptive role (tp tooth)
proprioceptive role (chewing not aware of forces)
35
what are the nerve endings of PDLM
ruffini nerve endings
36
what are the affreents for PDLM's
A beta axons
approx 300 per tooth
37
what are the cell bodies in PDLM's
V ganglion
mesencephalic nucleus - proprioception
38
what studies PDLM in animals
cat canine prep
localise indie receps
single fibre recordings
39
what studies PDLM in humans
recordings from IAN
discrete forces applied to teeth
40
what are PDLM properties
no branched axons between adjacent teeth PDLs easy to localise
innervation density higher at apex
41
what is the adequate stimulus for PDLM
tension in PDL due to pressure applied to tooth
tooth moves around in fulcrum
42
what does the amount of PDLM activity dept on
direction of applied force
magnitude force
adaptation props
threshold of receps
position of receps in PDL
43
