| Well... the whole idea behind cryonics is that the people preserved with current technology can be revived/reconstructed with future technology. Asking for a full preservation & resuscitation today is demanding evidence that wouldn't exist even in the case that cryonics works. That said, there is evidence available today. 21st Century Medicine is a company that does research on cryoprotectants. Their chief science officer is Greg Fahy, who co-invented the first method for cryopreserving embryos[1]. 21st Century Medicine's primary goal is to research new ways of cryopreserving tissues. This is already useful for research and some tissue banking (embryos, corneas, etc). If improvements continue, it could allow for organ banking. But the brain is an organ, and cryopreservation technologies work quite well on it. For example, 21st Century Medicine can take a slice of a rat's hippocampus, cryopreserve it, and thaw it. Afterwards, it's still viable tissue.[2] This is very important, as the hippocampus is not only crucial for memory consolidation, but it's the part of the brain most vulnerable to ischemic damage (especially the CA1 region). 21st Century Medicine has also experimented with whole organs. They've taken a kidney from a rabbit, cryopreserved it, thawed it, and transplanted it back into the rabbit. Then, after removing the remaining kidney, the vitrified-and-thawed kidney kept the rabbit alive indefinitely. Alcor uses the same cryoprotectants as this experiment. If cryonics works, this is exactly the sort of evidence you'd expect to see today. Granted, it probably won't work, but the expected value is positive. 1. Ice-free cryopreservation of mouse embryos at −196 °C by vitrification (http://www.nature.com/nature/journal/v313/n6003/abs/313573a0...) 2. Cryopreservation of rat hippocampal slices by vitrification (http://www.21cm.com/pdfs/hippo_published.pdf) 3. Physical and biological aspects of renal vitrification (http://www.21cm.com/pdfs/12FahyORG5-3%5B1%5D.pdf) |