Flashcards in Mechanoreception No.1 Deck (43)
1
what is mechanorception
detection of mechanical stimuli
with mechanoreceptors
2
what is adequate stimulus
pressure
vibration
tension
3
what is touch
sensory experience when mechanoreceptors are excited
involves CNS
4
what is exteroceptive
give information about things coming into contact with the body
5
what is proprioception
awareness of position
6
what is exteroceptors
muscosala nd skin receps
- mehanoreceps
-nociceptors
-thermoreceps
- chemoreceps
PDL Mechanoreceps
7
what are proprioceptors
PDL mechanoreceps
muscle spindles
joint recess
golgi tendon organs
inner ear
8
what do the mechanorecps of mucosa do
food texture- swallow food suitable
imp for mastication
9
what is function of PDL ligament mechanoreceps
forces of teeth
10
what are the mechanoreps in muscle
muscle spindles - monitor muscle length
11
what are mechanoreceps in joint recess useful for
joint position and movement
12
what sit he effect of stimulation of mechanorecps
sensation of touch
reflexes - jaw jerk, salivary reflexes
interact other sensory modalities - rubbing
13
what is the theory of vibraject
vibrating to activate the mechanorecps with vibration at same place of place activating nociceptors therefore trying to gate close and inhibit 3pain path
14
types of mechanoreceptorrs
physioloial classification
- aaptative properties -receptive field size
anatomical classification
15
what is rapidly adopting
AP force fires and then stops and adapts to force and maybe fires again when force goes off respond to changing states
16
what si slow adapting
apply same force and some receptors fire ad detect AP's thro whole duration doesn't adapt or very slow adapts
17
what are the four types of mechanoreceps
RA I
RA II
SA I
SA II
18
what is a receptive field
the area where a stimulus will affect the receptor covered by one receptor
19
what are the properties of RA I
small receptive field and rapid adaptation
20
what are the properties of RA II
large receptive field and rapid adaptation
21
what are the properties of SA I
small receptive field and slow adaptation
22
what are the properties of SA II
large receptive field and slow adaptation
23
what are some mechanoreceptors
meissners corpuscle
pacianian corpuscle
merkel cells
Ruffini ending
24
what are some RA I receptors
preset in
- oral mucosa
- vermillion border
- mucosa of lip
- hard palate
25
what are some RA II receptors
pacinian corpuscles
depp in mucosa
rare in oral mucosa
26
what are some SA I receptors
present in
- tongue
- lips
- cheeks
27
what ar some SA II Receptors
ruffini endings
PDL
28
what is transduction
mechanical to electrical energy
causes deep to AP
29
what is a parent axon
type nerve carry info
A- beta large myelinated fibres- fast
30
what are touch thresholds
lips and oral mucosa - 10 mg
teeth 0.01N
sense of being touched
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