Lecture 10 - Pain Part 1 Flashcards
define pain -
=An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage
Pain … What’s the big deal? -
=• #1 complaint to physicians • Massive health care costs • Massive personal costs
what is The Significance of Pain -
=• It hurts!
• Minor pains provide low-level feedback • Major pain leads us to seek help
• It affects us and others
what is the Old model - Specificity Theory of pain -
=• Direct relationship between the degree of tissue damage and the intensity of pain experienced
• Pain transmission was theorized to have an exclusively ascending pathway from the site of injury to the brain
what are problems with the old model - specificity theory of pain -
=Can not explain chronic pain
• Continued pain despite lack of tissue damage
Can not explain differences in pain reports and pain behaviours between individuals
Can not explain phantom limb pain
explain Pain as a Psychological Experience -
=• Pain is a fundamentally psychological experience
• The degree to which it is felt/how incapacitating it is depends a lot on how it is interpreted
explain the study of soldiers and pain the the 1959 study -
=Beecher (1959) observed wartime injuries
• Only 1⁄4 requested morphine (painkiller) for severe/painful wounds
• Civilian practice, 80% of patients demanded
• Concluded that meaning/interpretation of pain substantially determines how it is experienced
• Soldier: injury = alive (being sent home)
• Civilian: injury = unwelcome interruption of valued activities
why is Ronald Melzack important -
=contributions to pain field, collected descriptive words of pain (how people describe pain) and people used them to study and train pan conditions , gate control
what is gate control -
=Pain experience is jointly determined by physiological, motivational, cognitive, and affective variables…. there are two paths; ascending and inhibitory descending. Many different fibres but essentially they each play a role in the perception of pain. If the paths are blocked pain cannot be transmitted to/from the brain
what are the three fibres involved in gate control theory -
=A-delta fibres, C-fibre, A-Beta bibres
A-delta; description, type of pain, function, pain gate modulation (open or close) -
=small, myelinated fibres.
transmit first pain and sharp pain rapidly
affects sensory aspects of pain
opens gate
c-fibres; description, type of pain, function, pain gate modulation (open or close) -
=unmyelinated fibres
transmit secondary dull or aching pain
affects motivational and affective elements of pain
opens gate
a-beta fibres; description, type of pain, function, pain gate modulation (open or close) -
=large diameter myelinated fivres
transmit info about vibration and position
concurrent stimulation can suppress pain transmitted by c-fibres
closes gate
Gate-control theory of pain; factors that open the gate (increase pain) -
=Mental; focusing on the pain, boredom due to minimal involvement in life activities, non-adaptive attitudes
emotional stress; depression, anxiety, worry, tension, anger
physical factors; extent of injury or trauma to the area, readiness of the nervous system to send pain signals
Gate-control theory of pain; factors that close the gate (decrease pain) -
=mental; life involvement and increased interest in life activities, intense concentration, adapt attitudes
emotional factors; relaxation, positive emotions, adequate rest
physical factors; medication, counter-stimulation (cold, massage, acupuncture)