Pain_L5 - PO - Copy

Health Psychology Lecture 5: Ouch! (Pain)

Dr Brian Lovell

Importance of Pain

  • Pain as a Protective Mechanism

    • Sets limits on activities to avoid damage.

    • Informs us when to stop activities to prevent injury.

    • Helps us remember to avoid harmful stimuli (e.g., hot surfaces).

    • Provides feedback for bodily system adjustments (e.g., posture shifts, changing sleeping positions).

    • Intense pain can lead to seeking medical treatment.

Defining Pain

Duration

  • Acute Pain (0-6 months)

    • Examples: stubbing a toe or breaking a bone.

    • Can recur (e.g., migraines).

  • Chronic Pain (more than 6 months)

    • Can be benign (consistent intensity, e.g., back pain) or progressive (increasing intensity, e.g., arthritic pain).

Nature

  • Severity

    • Ranges from mild discomfort to excruciating.

  • Type

    • Pain descriptors: stabbing, shooting, piercing, throbbing, dull, aching.

  • Pattern

    • Variants: brief, continuous, sporadic, intermittent, kinetic.

Measuring Pain

  • Subjectivity makes pain difficult to measure.

    • Individuals experience pain differently.

  • Measurement approaches:

    • Use of questionnaires and diaries.

    • Observations of pain behaviors (e.g., grimaces, posture changes).

    • Laboratory pain induction techniques (e.g., cold pressor).

    • McGill Pain Questionnaire for assessment.

Biological Theories of Pain

  • Pain Transmission Pathways

    • Pain receptors in skin transmit signals via afferent nerves to the brain.

    • Efferent nerves relay responses back to injury sites.

    • Pain perception occurs when neural stimulation exceeds a threshold.

Specificity and Pattern Theories

  • Specificity Theory: Pain is detected by specific receptors.

  • Pattern Theory: Pain signals vary in patterns of activity.

  • Ascending and Descending Pathways:

    • Afferent nerves (ascending) bring signals to the brain; efferent nerves (descending) send responses.

Limitations of Biological Theories

  • Both specificity and pattern theories have limitations:

    • Cases exist where pain is experienced without appropriate receptors.

    • Psychological factors play a significant role.

Phantom Limb Pain

  • Occurs when individuals feel pain in an absent limb.

    • Common among those with spinal cord injuries; up to 70% exhibit phantom pain.

Congenital Analgesia

  • Individuals with this genetic disorder experience a lack of pain sensation.

  • Examples of real-life cases highlight the challenges faced without pain perception.

Psychological Factors Affecting Pain

Episodic Analgesia

  • Focused distraction can diminish pain sensation during injury.

    • Examples from wartime experiences demonstrate lack of awareness despite severe injuries.

Attention and Pain

  • Studies (e.g., James et al, 2002) showcase differences in pain perception when individuals focus on pain versus distraction.

Meaning of Pain

  • Differences in pain relief requests among soldiers and civilians observed during WWII (Beecher et al, 1959).

    • Soldiers valued injuries differently due to implications for 'going home.'

Mood and Pain

  • Study by Pinerua et al (1999) indicates a correlation between depression and pain perception under cold pressor conditions.

Bio-Psycho-Social Model of Pain

Gate Control Theory

  • Suggests a 'gate' mechanism in the spinal column that can open or close based on emotional and environmental factors.

    • Open Gate: Negative emotions, focus on pain, boredom, lack of medication.

    • Closed Gate: Positive emotions, distraction, medication, relaxation.

Additional Resources

  • Further readings and videos on pain mechanisms and specific case studies.

Next Week's Topic

  • Stress (Discussion in two weeks).