1. Can Hand Disownership in the
Rubber Hand Illusion Reduce Pain?
Simon van Rysewyk
Post-Doctoral Fellow
Graduate Institute of Medical Humanities
Taipei Medical University

2. Pain
‘An unpleasant sensory and emotional experience
associated with actual or potential tissue damage,
or described in terms of such damage.’ (IASP)
What does this pain definition imply?
Are there other important features of pain?
RHI Pain
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3. Pain
The multiple components of pain can separate:
• Nociception is not pain
– phantom pain, allodynia, SIA
• Pain sensation is not always painful
– frontal lobotomy, opiate analgesics
The link between pain components is not always
strong.
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4. Types of Nociceptive Pain: Superficial
Fast (‘first pain’)
• sharp, pricking
• acute
• skin, muscles,
peripheral nerves
• Aδ III fibers
• neospinothalamic
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5. Types of Nociceptive Pain: Superficial
Burning
• burning, sore
• acute, chronic
• skin, muscles
• C IV fibers
• archispinothalamic,
paleospinothalamic
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6. Types of Nociceptive Pain: Deep
Slow (‘second pain’)
• dull, aching
• chronic
• viscera, joints,
tendons
• C IV fibers
• paleospinothalamic
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7. RHI Pain
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8. Nociceptive Pain and the RHI
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9. Can pain be felt in a rubber hand?
Capelari et al. (2009)
Aim: To study the interaction between vision,
touch, proprioception, and pain.
Hypothesis: Nociceptive pain will inhibit the RHI
because illusory localization of noxious stimuli
may lead to actual tissue damage.
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10. Capelari et al. 2009
Conditions: synchronous, asynchronous (tactile
± nociceptive)
Materials: paint brush, sharp pin
Measures: VAS (0-10 cm, RHI magnitude), Drift,
2 questionnaires (Botvinick & Cohen (1998)
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11. Capelari et al. 2009
Procedure:
4 min. stroking right
index fingers both
hands
randomized conditions
questionnaires were
completed after the
experiment.
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12. Capelari et al. 2009
Main Results:
80% tactile RHI
77% tactile-nociceptive RHI
Subject RHI sensation mostly in response to
visible stimuli.
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13. Mean VAS and SE per stimulus mode
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14. Mean VAS and SE for drift per condition
*p ˂ 0.001
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15. Capelari et al. (2009)
Implications for Pain:
Standard RHI does not inhibit nociceptive pain.
RHI can alter pain-location.
Pain localization involves similar mechanisms to
those for innocuous touch.
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16. Pain Reduction and RHI: Hypothesis
RHI disrupts thermoregulation: ↓ in skin
temperature (Moseley et al. 2008)
RHI disrupts immunoregulation: ↑ reactivity to
intradermal histamine (Barnsley et al. 2012)
Hypothesis: Since tissue damage threatens
homeostasis, RHI may reduce pain.
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17. Mohan et al. 2013
Aim: To study if RHI can reduce pain.
Hypothesis: RHI will have an analgesic effect on
pain evoked by noxious stimuli given on the real
right hand.
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18. Mohan et al. 2013
Conditions: synchronous, asynchronous (tactile
± noxious or innocuous temperature)
Materials: paint brush, heat probe
Measures: VAS (0-10 cm), de-briefing
questionnaire (Botvinick & Cohen, 1998)
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19. Mohan et al. 2013
Procedure:
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20. Mohan et al. 2013
Main Results:
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21. Mean & SE for questionnaire
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22. Mean & SE for pain ratings
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23. Mohan et al. 2013
Implications for Pain:
Standard RHI does not reduce nociceptive pain.
Pain components can be independently
manipulated.
Pain localization involves similar mechanisms to
those for innocuous touch.
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24. Can Left-Hand RHI Reduce Pain?
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