Mechanoreception

Question 1

what is mechanoreception?

Answer 1

the detection of mechanical stimuli (pressure, vibration, tension) by mechanoreceptors through distortion.

Question 2

what is exteroception?

Answer 2

gives information about things coming into contact with the body

Question 3

what is proprioception?

Answer 3

knowing where parts of the body are (subconscious)

Question 4

what is touch?

Answer 4

the sensory experience when mechanoreceptors are excited (CNS)

Question 5

Physiological classification of mechanoreceptors

describe rapidly adapting mechanoreceptors, what do they tell u?

Answer 5

only fires when force is changing (increase/decrease in pressure)

How fast applying the force

Question 6

physiological classification of mechanoreceptors

describe slow adapting mechanoreceptors, what do they tell u?

Answer 6

receptor fires whole time force is applied
Magnitude of the force

Question 7

Question 8

what is receptive field?

Answer 8

amount of tissue that is governed by one nerve

Question 9

a smaller receptive field means what?

Answer 9

more detailed information (e.g. fingertips)

better 2-point discrimination

Question 10

what classifications is a RA I mechanoreceptor?

Answer 10

rapid adapting
small receptive field

Question 11

what classifications is a RA II mechanoreceptor?

Answer 11

rapid adapting
large receptive field

Question 12

what classification is SA I mechanoreceptor?

Answer 12

slow adapting
small receptive field

Question 13

what classification is SA II mechanoreceptor?

Answer 13

slow adapting
large receptive field

Question 14

what anatomical classification of mechanoreceptor is this?

Answer 14

meissner’s corpuscle

Question 15

what anatomical classification of mechanoreceptor is this?

Answer 15

pacinian corpuscle

Question 16

what anatomical classification of mechanoreceptor is this?

Answer 16

merkel cells

Question 17

what anatomical classification of mechanoreceptor is this?

Answer 17

ruffini ending

Question 18

what Physiological classification of mechanoreceptor is meissner’s corpuscle?

Answer 18

RA I

Question 19

what Physiological classification of mechanoreceptor is ruffini ending?

Answer 19

SA II

Question 20

what Physiological classification of mechanoreceptor is merkel cells?

Answer 20

SA I

Question 21

what Physiological classification of mechanoreceptor is pacinian corpuscle?

Answer 21

RA II

Question 22

what is 2 point discrimination test?

Answer 22

• How far apart does it need to be to feel it as two separate points
  
  • Reflects innervation density and receptive field size
    Fingertip is very discriminative due to high innervation density and small receptive field

Question 23

2 point discrimination test

Question 24

what nerve endings are PDL mechanoreceptors (PDLMs)?

Answer 24

Ruffini endings SA II

Question 25

quick revision

Question 26

what afferents do PDLMs have?

Answer 26

Ab axons

Question 27

where are the cell bodies for PDLMs?

Answer 27

V ganglion Mesencephalic nucleus - group of primary afferent cell bodies in the CNS

Question 28

where are the synapses for PDLMs?

Answer 28

Main sensory nucleus V nucleus

Question 29

sensory pathway of PLDMs

Question 30

are there branched axons from PDLMs?

Answer 30

no, nerves only supply the PDL of one tooth -> easy to localise

Question 31

the innervation density of PDLMs is higher where?

Answer 31

apex

Question 32

what is the stimulus for PDLMs?

Answer 32

tension

Question 33

what is the physiological classification of PDLMs apically? why?

Answer 33

slow adapting low threshold to activate it Smaller stimulus apically compared to cervically

Question 34

what is the phsyiological classification of PDLMs cervically? why?

Answer 34

fast adapting high threshold requires higher force to activate it

Question 35

what is the function of PDLMs?

Answer 35

fine motor control

Question 36

what is surround inhibition?

Answer 36

presynaptic inhibition -> sharpens touch perception Inhibits the smaller signals from around the stimulus, enhancing the contrast, to give exact location occurs during processing at the first synapse: V ganglion and mesencephalic nucleus

Question 37

what is the sensory pathway for PDLMs?

Answer 37

mechanoreception processing at first synapse processing in thalamus conscious perception - somatosensory cortex