Hoofdstuk 11 Flashcards
Pain
= sensory and emotional experience of discomfort, usually associated with actual or threatened tissue damage or irritation
- organic pain = pain we experience that is clearly linked to tissue pressure or damage
- psychogenic pain = pain that could result from psychological processes
- acute pain = less than 3 months (after that its chronic)
the dimension of pain involving organic and psychogenic causes is viewed as a continuum rather than a dochotomy
The condition Somatic Symptom Disorder
when people experience long-term pain as a part of excessive concerns for their physical symptoms or health
Sleep + Pain
1) high level of pain followed by poor sleep (vicious circle)
2) pain + intrusive thoughts impair sleep
3) long term sleep deprivation increases negative affect, sensitivity to pain and amount of pain experienced
Benign = harmless
Malignant = injurious
3 types of chronic pain
1) chronic-recurrent
- benign causes
- repeated + intense episodes of pain (migrain)
2) chronic-intractable-benign
- discomfort that is present all the time
- varying levels of intensity
- not related to underlying malignant condition
3) chronic progressive pain
- continuous discomfort
- associated with malignant condition
- increasingly intense (arthritis/cancer)
Sense of pain has 3 unique properties
1) receptor cells for pain are different form those of other perceptual systems
2) the body senses pain in response to many types of noxious stimuli (physical pressure, lacerations, heat/cold)
3) pain perception always includes a strong emotional component
Chemicals at injury
serotonine, histamine and bradykinin
- the afferent nerve endings that respond to pain stimuli and signal injury are called NOCIreceptors (exist in every bodytissue but the brain)
Pain signals by peripheral fibers: A-delta and C-fibers
A-delta:
- coated with myelin
- sharp, well-localized and distinct pain experience
- motor + sensory areas in the brain
C-fibers
- slower transmission
- experiences of diffuse dull burning or aching pain sensations
- terminate in brainstem and forebrain
Referred Pain
results when sensory impulses from an internal organ and the skin use the same pathway in the spinal cord
Pain without Noxious stimulus
neuropathic pain (result from current or past disease/damage in peripheral nerves
3 common neuropathic pain syndromes
1) neuralgia (= extremely painful, recurrent episodes of intense shooting or stabbing pain, along the course of a nerve. Occurs suddenly and without apparent cause, attacks more from innocuous stimuli, rather than by noxious ones)
2) causalgia (complex regional pain syndrome - recurrent episodes of severe burning pain, triggered by minor stimuli, unpredictable)
3) phantom limb pain (recurrent/continuous, shooting/burning or cramping)
Specificity Theory
argues that the body has a separate sensory system for perceiving pain
Pattern theory
proposed that the receptors for pain are shared with other senses such as touch
- both the specificity theory and the pattern theory do not attempt to explain why the experience of pain is affected by psychological factors, such as the person’s ideas about the meaning of pain, beliefs about the likelihood of pain and attention to/distraction from noxious events
Gate Control Theory of Pain Perception (melzack & wall)
- at the heart of this theory is a neutral “gate” that can be opened in varying degrees, thereby modulating incoming pain signals before they reach the brain
- the theory proposes that the gating mechanism is located in the spinal cord (substantia gelatinosa of the dorsal horns)
- after passing the gate, they activate transmission cells, which send impulses to the brain
- the greater the output, the greater the pain
3 factors for opening & closing the gate
1) amount of activity in pain fibers
2) amount of activity in other peripheral fibers/A-Beta-Activity = closes
3) messages descending from the brain
Stimulation to periaqueductal grey area can induce analgesia
= SPA Stimulation-Produced-Analgesia
- morphine works a painkiller by activating the brainstem to send impulses down the spinal cord
- SPA is the phenomenon whereby stimulation to the brainstem produces insensitivity to pain
- transmission cells are activated to send pain signals to the brain
- activation is triggered by neurotransmitter called Substance P, that is secreted by pain fibers and crosses the synapse to the transmission cells
- SPA occurs when another fiber’s release of Substance P (=endorphine)
Endorphine is an Endogenous Opioid (lichaamseigen)
