Part 1, phil heywood, phsl

Question 1

function of sensory receptors of skin

Answer 1

convert physical stimulus into APs in primary sensory neuron / transduction

Question 2

thermoreceptors

Answer 2

different types are activated at warm and cold temperatures, thermoreceptors are especially responsive to changing temperatures

Question 3

proprioceptors sense

Answer 3

position of limbs by skin mechanoreceptors

Question 4

touch receptors

Answer 4

sensitive to mechanical deformation

Question 5

nociceptors sense what and respond to what

Answer 5

pain, respond to extreme mechanical, temperature and chemical stimuli

Question 6

bare nerve endings sense

Answer 6

pain

Question 7

meissners corpuscle sense

Answer 7

light touch

Question 8

merkel disc sense

Answer 8

touch

Question 9

Ruffini endings sense

Answer 9

stretch

Question 10

pacinian corpuscle sense

Answer 10

pressure and vibration

Question 11

sensory coding includes

Answer 11

modality, intensity, location and duration

Question 12

modality

Answer 12

specificity of receptors for example touch vs temperature

Question 13

intensity of sense is determined by

Answer 13

freq of APs in each axon

Question 14

location of sense is determined by

Answer 14

mapping of receptive fields of individual primary afferents to specific cortical locations (somatotropic representation)

Question 15

duration of sense is determined by

Answer 15

rapidly adapting receptors respond briefly, even if stimulus is sustained, detect movement, changing pressure. slowly adapting receptors signal true duration of stimuli

Question 16

what is the axon path for pain and temperature

Answer 16

cross low in spinal cord, anterolateral of spinothalamic

Question 17

axons for fine touch and proprioception

Answer 17

cross high in the medulla, dorsal column and medial lemniscal pathways

Question 18

lateral inhibition

Answer 18

fundamental mechanism to increase accuracy of sensory information

Question 19

what mediates lateral inhibition

Answer 19

inhibitory interneurons

Question 20

lateral inhibition results in

Answer 20

centre surround inhibition

Question 21

primary somatosensory cortex senses

Answer 21

nociception which is carried by two types of nerve fibres

Question 22

C fibres in the primary somatosensory cortex

Answer 22

smallest diameter - unmyelinated
slow conduction velocity
signal ongoing damage
polymodal

Question 23

A fibres in the primary somatosensory cortex

Answer 23

small diameter - myelinated
fast conducting velocity
signal acute onset of painful stimuli
primarily mechanoreceptors

Question 24

hyperalgesia

Answer 24

pain pathways become more sensitive following injury of inflammatory disease

Question 25

describe gating

Answer 25

gating of pain impulses by non-painful stimuli of nearby nerves

Question 26

TENS

Answer 26

trans epidermal nerve stimulation

Question 27

what are endogenous opiates

Answer 27

released from synapses natural analgesia for acute response to pain

Question 28

what are endocannaboids

Answer 28

decrease long term sensitivity to pain, act on pain receptor

Question 29

referred pain

Answer 29

feelings from viscera referred to body surface

Question 30

two causes of phantom limb

Answer 30

ongoing activity in nerves that used to come from that body part
or
invasion of cortical representation from theat [art by intact body regions