In what sounds like a plot from an animated sci-fi film, I’ve just found a remarkable study where Japanese researchers put a Yoga Master in a brain scanner and fired lasers at him because he claimed not to be able to feel pain while meditating.
It turns out that he showed significantly less brain activity in areas typically activated by pain when meditating.
Intracerebral pain processing in a Yoga Master who claims not to feel pain during meditation.
Eur J Pain. 2005 Oct;9(5):581-9.
Kakigi R, Nakata H, Inui K, Hiroe N, Nagata O, Honda M, Tanaka S, Sadato N, Kawakami M.
We recorded magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) following noxious laser stimulation in a Yoga Master who claims not to feel pain when meditating. As for background MEG activity, the power of alpha frequency bands peaking at around 10 Hz was much increased during meditation over occipital, parietal and temporal regions, when compared with the non-meditative state, which might mean the subject was very relaxed, though he did not fall asleep, during meditation.
Primary pain-related cortical activities recorded from primary (SI) and secondary somatosensory cortices (SII) by MEG were very weak or absent during meditation. As for fMRI recording, there were remarkable changes in levels of activity in the thalamus, SII-insula (mainly the insula) and cingulate cortex between meditation and non-meditation. Activities in all three regions were increased during non-meditation, similar to results in normal subjects. In contrast, activities in all three regions were weaker during meditation, and the level was lower than the baseline in the thalamus.
Recent neuroimaging and electrophysiological studies have clarified that the emotional aspect of pain perception mainly involves the insula and cingulate cortex. Though we cannot clearly explain this unusual condition in the Yoga Master, a change of multiple regions relating to pain perception could be responsible, since pain is a complex sensory and emotional experience.
I have an image of scientists shielding their eyes as lasers fail to penetrate the force field of the Yoga Master who serenely hovers a few inches above the ground, although I suspect that’s because I’ve read too many manga comics
Link to PubMed entry for study,