Pain and Thermodynamics Flashcards
Specific theory
- pain is directly related to the amount of tissue injury
Gate control theory
- mociceptive pain opens gate
- non-nociceptive pain closes gate (touch)
Neuromatrix theory
- patterns of nerve impulses
- genetic, psychological and cognitive experiences (phantom pain)
A fibres
- larger, myelinated, rapid transmission
- sharp, well localized, “fast” pain sensation
- cause reflex of withdrawl
C fibres
- more numerous, smaller, and unmyelinated
- local in muscle, tendon, body organs, skin
- dull, aching, or durning; constant
Anterior spinothalmic tract
fast impulse or acute sharp pain
lateral spinothalamic tract
slow impulses for dull or persistant pain
sensory-discriminative system
- identifying presence, character, location, and intensity of pain
– makes us want to withdraw our hand or act to stop pain
Affective-motivational system
– conditioned avoidance behaviors and emotional responses to pain
– includes depression, anger, anxiety
Cognitive-evaluative system
– individual’s learned behaviour
– can modulate perception of pain
excititory neurotransmitter function
reduce activation thershold; increase responsiveness to nociceptors
excitatory neurotransmitter examples
prostiglandins, histamines, bradykinin, lymphokines
inhibitory neurotransmitter example
GABA, norepinephrine and serotonin
Endogenous opiods function
inhibit transmission of pain impulses
endogenous opiods examples
morphinelike neuropeptides
what is the most common enkephalins
endorphins
enkephalins function
- produce an exhilaration as well as pain releif
acute pain time
< 3 months
chronic pain time
> 3 months