Also, from the link: "It is not possible to know at what time in relation to the near-death experience itself the measurements were taken (the study cannot prove causation)."

Poor Bill! I personally would welcome any scientific explanation and analysis of the near-death experience, but in my view, any explanation would not negate the experience itself.

Just as placebo-generated responses are well-documented phenomena, its occurrence does not invalidate any medicine's efficacy. It only means, in my opinion, that we still don't know squat (awful phrase!) about how the body, mind and spirit interact. Placebos may make it possible in some cases for the body to heal itself, perhaps through mind and spirit.

So, perhaps, high levels of CO2 make it possible to access the mind/spirit?

On the other hand, even though this study was peer-reviewed it may be perfectly meaningless: Out of 52 people studied, only 11 reported the experience. Eleven instances a summer do not make.