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An fMRI study measuring analgesia enhanced by religion as a belief system. Wiech , Farias , Kahane , Shackel , Tiede , & Tracey (2008). Introduction . Stories of diminished physical pain or pain tolerance due to religious belief
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An fMRI study measuring analgesia enhanced by religion as a belief system Wiech, Farias, Kahane, Shackel, Tiede, & Tracey (2008)
Introduction • Stories of diminished physical pain or pain tolerance due to religious belief • Research has shown that high-level cognitive processes such as placebo-induced analgesia, emotional detachment, and perceived control over pain can reduce pain intensity. • Religious individuals → positive framing • fMRI studies and the right ventrolateral prefrontal cortex (VLPFC)
Research Questions • 1. Can religious belief be shown to modulate pain in a controlled experimental setting? • 2. Is such modulation of pain by religious belief mediated by the right VLPFC?
Methods • Subjects: • 12 religious (Catholic) and 12 atheist/agnostic healthy individuals • Age 19-34 • Questionnaire → All religious participants attended mass at least once/week and prayed everyday • QUESTION: Should atheists be used in the control group? • Design: • 2 x 2 factorial design • GROUP (religious vs. non-religious) → between-subject • CONDITION (religious vs.non-religious) → within-subject • “Vergine Annunciate” by Sassoferrato • “Lady with an Ermine” by da Vinci
Methods • Visual stimuli: • (1) The religious image had to reliably evoke a religious mind set in believers and (2) the non-religious picture had to be sufficiently similar to the religious one in order to minimize the influence of confounding factors. • Image of Jesus may introduce confounding factors • Religious → evoked most powerful religious feelings • Non-religious → rated most similar to religious image • Procedure: • Electrical stimulation to the back of the left hand • fMRI session • Coping and familiarity rating using visual analog
Results • Pain ratings: • Significant effects for CONDITION and GROUP x CONDITION • GROUP was not significant → Religious not less sensitive to pain • Atheist group rated pain same in both conditions
Results • Affectedness ratings: • Significant effects for GROUP and GROUP x CONDITION • Religious sample → more positive ratings for religious image • Atheist sample → more positive ratings for non-religious image • *Both groups indicated differences in preferred image but only religious group also indicated pain reduction when viewing preferred image
Results • Coping and familiarity ratings: • Both factors and interaction significant for coping • Religious → Virgin Mary more helpful in coping • Atheist → Both pictures equally helpful • Participants rated both pictures as equally familiar. • Neuroimaging data: • No significant differences between groups for pain-related brain activation • Religious group/ religious image → significant activation in right VLPFC and pons/ventral midbrain • *Support for 2nd research question
Results • Neuroimaging data: • Activation in right VLPFC not due to preferential liking • → no activation for atheist group with preferred image • Pons/midbrain activation found in both groups • → likely due to preferential liking
Results Right VLPFC – most strongly associated with pain intensity (negative) Pons/midbrain area – most strongly associated with affectedness (positive)
Discussion • Religious individuals are able to lessen the perceived pain intensity when they are presented with a religious image. • (1) Distraction effect • (2) Motivational priming • (3) Reappraisal – a process of reinterpreting the meaning of a stimulus leading to a change in one’s emotional response to it. • → Supported by data • → Distraction and motivational priming – preferential liking should have produced a reduction in pain
Discussion • Right VLPFC • Active for religious group/religious condition, leading to a decrease in perceived pain intensity • Active in previous studies of pain modulation • Pons/ventral midbrain • More strongly related to affectedness → active during preferred condition • Unknowns • Is the pain-reduction effect started by the VLPFC or is the VLPFC compelled by the dorsolateral prefrontal cortex? • QUESTION: Do you think similar pain-reduction effects can occur using stimuli that are not religious in nature but have similar cultural and nurturing influences?
Andes Survivors • Catholic → familiar with image of Virgin Mary • Prayed the rosary every night → Hail Mary • Likely helped the survivors cope with the pain associated with injuries from crash, hunger, and the cold.