This study says that CO2 maybe the cause of the near death experience where they report a reunion with loved ones, a bright light etc. The problem is that other researchers have previously looked at blood carbon dioxide levels in relation to near-death experiences. In contrast to the Slovenian group's findings, Dr.Bruce Greyson says "what few data we have point in the opposite direction."
One earlier study found an association between these experiences and below-average carbon dioxide levels, whereas another failed to detect a significant difference in patients with versus without near-death experiences.
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