Neuropreservation

Neuropreservation is cryopreservation of the human brain with the intention of future resuscitation and regrowth of a healthy body around the brain.^[1] Usually the brain is left within the head for physical protection, so the whole head is cryopreserved. Neuropreservation is a type of cryonics procedure and, like cryonics in general, is considered highly speculative and reliant on future technologies.^[2] A cryonics patient who undergoes neuropreservation is said to be a neuropatient.

Recently, the procedure is most often done for the sake of vitrification of the brain (neurovitrification), which has not yet been perfected on a full body level and is seen by some as a superior method of preservation, causing almost no tissue damage.^[3]

Future recovery prospects

Cryonics proponents (providers Alcor and the Cryonics Institute, along with the community of people signed up for or interested in the process) claim that extremely advanced future technologies will be required for successful cryonics, such as mature nanomedicine.^[4] It is said these technologies must necessarily be capable of tissue and organ regeneration, so neuropreservation is just as likely (or unlikely) to work as whole body cryopreservation. Neuropreservation is typically less expensive than whole body cryopreservation,^[5] and can potentially result in better brain preservation because the process can be optimized for the brain. Neuropreservations are easier to maintain, and none has been lost to thawing as of yet.^[6]

The hypothetical future recovery process is said^[7] to involve programming cells on the brain to regenerate a new body around the repaired brain inside a fluid life support environment, requiring cell-by-cell repair technology, as cryonics in general would.^[2] News media sometimes report that new bodies are expected from cloning, but some cryonics experts dismiss cloning,^[8][2] claiming that nothing as crude as nuclear transfer or transplants will ever have to be used in cryonics. They believe the methods used for recovery of neuropatients will be an extension of mainstream medical technologies that will someday be developed to regrow lost limbs and treat severe trauma.^[2]

Another, equally speculative technology for the revival of neuropatients, or cryonics patients generally, is mind transfer. Although philosophically more radical, transferring the information content of a cryopreserved brain into an artificial brain may be no more or less feasible than re-growing a biological body, especially to a society with technology capable of reviving cryopreserved brain tissue.

Advantages

Several advantages to neuropreservation over whole body preservation have been put forth.^[2] These include lower costs on the part of the patient and for storage, greater transportability in case of disaster, ease in reaching the brain with cryoprotectants and thus a better chance that the brain is preserved, and quicker cooling which may also increase likelihood of future recovery.^[2] Aubrey de Grey has theorized that neuropatients will be revived after procedures have been perfected on whole body patients, and therefore have better chances for revival.^[9]

History

Neuropreservation was first proposed in 1965 by cryonics co-creator Evan Cooper, proposed again in a speculative scientific paper by gerontologist George M. Martin in 1971, and independently proposed yet again in 1974 by Mike Darwin, and Fred and Linda Chamberlain. The Chamberlains were the founders of the Alcor Life Extension Foundation. In 1976 Fred’s father became the first of many neuropreservation patients at Alcor.^[10]

Prior to the year 2000, neuropreservation was performed by surgical separation of the body from the head (called cephalic isolation or "neuroseparation") at the end of cryoprotectant perfusion performed on the upper body via the ascending aorta.^[2] After that year, Alcor began performing cephalic isolation before cryoprotectant perfusion, in deep hypothermia, and then using the carotid and vetebral arteries directly for perfusion with cryoprotectants.

As of 2008, Alcor and KrioRus are the only cryonics organizations that offer neuropreservation. Other organizations, such as the other major provider, the Cryonics Institute, avoid it because they say it is bad for public relations. Alcor claims there are good technical justifications for neuropreservation, and that they will continue to offer it. Approximately three quarters of the cryonics patients stored at Alcor are neuropatients.

References

1. ^ http://www.alcor.org/Library/html/neuropreservationfaq.html
2. ^ ^{a b c d e f g} Bridge, Steve (1995). "The Neuropreservation Option: Head First into the Future". Cryonics. Alcor Life Extension Foundation. http://www.alcor.org/printable.cgi?fname=Library%2Fhtml%2Fneuropreservationoption.html. Retrieved 2009-08-25. 
3. ^ Schweid, Richard (2006). Hereafter: Searching for Immortality. Thunder's Mouth Press. p. 45. ISBN 1560256575. 
4. ^ Regis, Ed (1991). Great Mambo Chicken And The Transhuman Condition: Science Slightly Over The Edge. Westview Press. pp. 81–82. ISBN 0201567512. 
5. ^ Quigley, Christine (1998). Modern Mummies: The Preservation of the Human Body in the Twentieth Century. McFarland. p. 143. ISBN 0786404922. 
6. ^ Perry, R. Michael (2000). Forever for All: Moral Philosophy, Cryonics, and the Scientific Prospects for Immortality. Universal-Publishers. p. 40. ISBN 1581127243. 
7. ^ http://www.alcor.org/Library/html/caseforneuropreservation.html
8. ^ http://www.alcor.org/FAQs/faq02.html#cloning
9. ^ Fryer, Jane (2006). "The Britons dying to get into the human deep freeze". Daily Mail. http://www.dailymail.co.uk/news/article-398188/The-Britons-dying-human-deep-freeze.html. Retrieved 2009-08-25. 
10. ^ Chamberlain, Fred & Linda (July 16, 2006). "FRC Jr.". Lifepact. http://www.lifepact.com/frcjr.htm. Retrieved 2008-05-20. 

External links

• Neuropreservation FAQ
• The Case for Neuropreservation
• But What Will The Neighbors Think? A Discourse On The History And Rationale Of Neurosuspension