Physiology - Pain Flashcards
what is pain?
an unpleasant sensory and emotional experienced associated with tissue damage
what are the four distinct processes in the physiology of pain?
transduction
transmission
modulation
perception
what is transduction of pain?
translation of a noxious stimulus into electrical activity at the peripheral nociceptor
what is transmission of pain?
propagation of pain signal as nerve impulses through the nervous system
what is modulation of pain?
modification/hindering of pain transmission in the nervous system
what is perception of pain?
conscious experience of pain, causes physiological and behavioural responses
what does pain begin with?
the activation of nociceptors
what are nociceptors?
specific primary sensory afferent neurones normally activated by intense noxious stimuli
what are the two subtypes of nociceptors?
A fibres
C fibres
what are A fibres?
mechanical/thermal nociceptors that are myelinated
what type of pain do A fibres mediate?
fast pain/first painless
what are C fibres?
unmyelinated nociceptors that respond to all noxious stimuli
what type of pain do C fibres mediate?
slow/second painful
what does nociceptive pain represent?
a normal response to injury of tissues by noxious stimuli
what provokes nociceptive pain?
intense stimulation of nociceptors
what causes inflammatory pain?
activation of the immune system
what does inflammatory pain cause?
heightened pain sensitivity
what does inflammatory pain discourage?
physical contact with affected site and movement
what are the two types of pathological pain?
neuropathic
dysfunctional
what causes neuropathic pain?
damage to neural tissue
how can neuropathic pain be perceived?
burning
shooting
numbness
pins and needles
what is the cause of dysfunctional pain?
no known cause
what is referred pain?
pain developed in one part of the body is felt in another area
what type of pain can be felt as referred pain?
deep/visceral pain
