Cryonics

For the study of the production of very low temperatures, see Cryogenics. For the low-temperature preservation of living tissue and organisms in general, see Cryopreservation. For the Hot Cross album, see Cryonics (album).
Technicians prepare a body for cryopreservation in 1985.

Cryonics (from Greek κρύος 'kryos-' meaning 'cold') is the low-temperature preservation of animals and humans who cannot be sustained by contemporary medicine, with the hope that healing and resuscitation may be possible in the future.[1]

Cryopreservation of people or large animals is not reversible with current technology. The stated rationale for cryonics is that people who are considered dead by current legal or medical definitions may not be dead according to the information-theoretic definition of death.[2] It is proposed that cryopreserved people might someday be recovered by using highly advanced technology.[3]

Cryonics procedures ideally begin within minutes of cardiac arrest, and use cryoprotectants to prevent ice formation during cryopreservation.[4] There are presently three cryonics service providers: Alcor and Cryonics Institute based in the US, and KrioRus in Russia.

Premises

A central premise of cryonics is that long-term memory, personality, and identity are stored in durable cell structures and patterns within the brain that do not require continuous brain activity to survive.[5][6] This premise is generally accepted in medicine; it is known that under certain conditions the brain can stop functioning and still later recover with retention of long-term memory.[7]

The further premise of cryonics is that brain structures encoding long-term memory can be preserved, or preserved well enough for the original state to be inferrable. Application of cryonics after clinical death additionally requires that these brain structures persist for some time after blood circulation stops.

Finally, cryonics is premised on the belief that future technology will be able to repair or regenerate tissue that is diseased, damaged or missing. It is assumed that the brain in particular will be restored based on maximum likelihood estimation of the original state from analysis of the preserved brain[8], at the molecular level if necessary. This future technology is usually assumed to be nanomedicine based on molecular nanotechnology. Alternative revival scenarios involve utilizing preserved brain information for mind uploading.

Some cryonics practices such as preserving people after long periods of clinical death follow a philosophical premise that it's wrong not to preserve people when there is any doubt about whether information theoretic death has occurred. The resulting imperative is that anyone who may have residual neuroanatomical traces of memory and personality, and who might therefore be saved by future medicine, should be made "a permanent patient."[9]

Obstacles to success

Preservation injury

Long-term preservation of biological tissue can be achieved by cooling to temperatures below -130°C.[10] Immersion in liquid nitrogen at a temperature of -196°C (77 Kelvin) is often used for convenience. Low temperature preservation of tissue is called cryopreservation. Contrary to popular belief, water that freezes during cryopreservation is usually water outside cells, not water inside cells. Cells don't burst during freezing, but instead become dehydrated and compressed between ice crystals that surround them. Intracellular ice formation only occurs if the rate of freezing is faster than the rate of osmotic loss of water to the extracellular space.[11]

Without use of cryprotectants, cell shrinkage and high salt concentrations during freezing usually prevent frozen cells from functioning again after rewarming. In tissues and organs, ice crystals can also disrupt connections between cells that are necessary for organs to function.[12] The difficulties of recovering large animals and their individual organs from a frozen state have been long known. Attempts to recover frozen mammals by simply rewarming them were abandoned by 1957.[13] At present, only cells, tissues, and some small organs can be reversibly cryopreserved.[14][15]

When used at high concentrations, cryoprotectants stop ice formation completely. Cooling and solidification without crystal formation is called vitrification.[16] The first cryoprotectant solutions able to vitrify at very slow cooling rates while still being compatible with tissue survival were developed in the late 1990s by cryobiologists Gregory Fahy and Brian Wowk for the purpose of banking transplantable organs.[17][18] This has allowed animal brains to be vitrified, warmed back up, and examined for ice damage using light and electron microscopy. No ice crystal damage was found; the cellular damage found had other causes related to the process. [19]

Revival

Those who believe that revival may someday be possible generally look toward advanced bioengineering, molecular nanotechnology,[20] or nanomedicine[21] as key technologies. Revival would require repairing damage from lack of oxygen, cryoprotectant toxicity, thermal stress (fracturing), freezing in tissues that do not successfully vitrify, and reversing the effects that caused the patient's death. In many cases extensive tissue regeneration would be necessary.

It has sometimes been written that cryonics revival will be a last in, first out process. People cryopreserved in the future, with better technology, may require less advanced technology to be revived because they will have been cryopreserved with better technology that caused less damage to tissue. In this view, preservation methods would get progressively better until eventually they are demonstrably reversible, after which medicine would begin to reach back and revive people cryopreserved by more primitive methods. Revival of people cryopreserved by early cryonics technology may require centuries, if it is possible at all. The "last in, first out" view of cryonics has been criticized because the quality of cryopreservation depends on many factors other than the era in which cryopreservation takes place.[22]

Legal issues

Legally, cryonics patients are treated as deceased persons.[23][24] Cryonics providers tend to be treated as medical research institutes. In France, cryonics is not considered a legal mode of body disposal;[25] only burial, cremation, and formal donation to science are allowed. However, bodies may legally be shipped to other, less restrictive countries for cryonic freezing.[26]

Ethical considerations

Cryonics views legal death as a perhaps sometimes pragmatically useful but fundamentally flawed and usually incorrect diagnosis which has no theoretical or philosophical justification. "Legal death" is usually just another name for a set of symptoms that have proven resistant to treatment by contemporary medicine. If death is not an event that happens suddenly when the heart stops (and "legal death" is often pronounced) this raises philosophical questions about what exactly death is. In 2005 an ethics debate in the medical journal, Critical Care, noted “…few if any patients pronounced dead by today’s physicians are in fact truly dead by any scientifically rigorous criteria.”[27] Ethical and theological opinions of cryonics tend to pivot on the issue of whether cryonics is regarded as interment or medicine. Many followers of Nikolai Fyodorovich Fyodorov, a Russian Orthodox Christian philosopher, see cryonics as an important step in the Common Cause project which he originated.[28]

In 1969, a Roman Catholic priest consecrated the cryonics capsule of Ann DeBlasio, one of the first cryonics patients.[29]

At the request of the American Cryonics Society, in 1995, philosopher Charles Tandy, [30] authored a paper entitled “Cryonic-Hibernation in Light of the Bioethical Principles of Beauchamp and Childress.” Tandy considered the four bioethical factors or principles articulated by philosophers Beauchamp and Childress as they apply to cryonics. These four principles are 1) respect for autonomy; 2) nonmaleficence; 3) beneficence; and 4) justice. Tandy concluded that in respect to all four principles “biomedical professionals have a strong (not weak) and actual (not prima facie, but binding) obligation to help insure cryonic-hibernation of the cryonics patient.”[31]

History

20th century

In 1922 Alexander Yaroslavsky, member of Russian immortalists-biocosmists movement, wrote "Anabiosys Poem". However, the modern era of cryonics began in 1962 when Michigan college physics teacher Robert Ettinger proposed in a privately published book, The Prospect of Immortality,[32] that freezing people may be a way to reach future medical technology. (The book was republished in 2005 and remains in print.) Even though freezing a person is apparently fatal, Ettinger argued that what appears to be fatal today may be reversible in the future. He applied the same argument to the process of dying itself, saying that the early stages of clinical death may be reversible in the future. Combining these two ideas, he suggested that freezing recently deceased people may be a way to save lives. In 1955 James Lovelock was able to reanimate rats frozen at 0 Celsius using microwave diathermy.[33]

Slightly before Ettinger’s book was complete, Evan Cooper[34] (writing as Nathan Duhring) privately published a book called Immortality: Physically, Scientifically, Now that independently suggested the same idea. Cooper founded the Life Extension Society (LES) in 1964 to promote freezing people. Ettinger came to be credited as the originator of cryonics, perhaps because his book was republished by Doubleday in 1964 on recommendation of Isaac Asimov and Fred Pohl, and received more publicity. Ettinger also stayed with the movement longer.

Demographics

Cryonicists are predominantly nonreligious white males; according to the New York Times, among living cryonicists, men outnumber women by about three to one.[35] As of 2015, Alcor has 104 male patients and 39 female patients.[36] However, cryonics pioneer Bob Nelson claims the majority of cryonics patients are women.[37]

In 2015 Du Hong, a 61-year-old female writer of children's literature, became the first known Chinese person to be cryopreserved.[38]

In popular culture

Suspended animation is a popular theme in science fiction and fantasy settings, appearing in comic books, films, literature, and television. A survey in Germany found that about half of the respondents were familiar with cryonics, and about half of those familiar with cryonics had learned of the subject from films or television.[39]

Famous people

Famous people who are cryopreserved

Among cryopreserved are James Bedford,[40] Dick Clair,[40] L. Stephen Coles (in 2014),[41] Thomas K. Donaldson,[40] FM-2030,[40] Hal Finney[42] (in 2014), Jerry Leaf,[40] and John-Henry Williams.[40] Baseball player Ted Williams is the best known cryopreserved patient.

Famous people associated with cryonics but who were not cryopreserved

The urban legend suggesting Walt Disney was cryopreserved is false; he was cremated and interred at Forest Lawn Memorial Park Cemetery.[43][44] Robert A. Heinlein, who wrote enthusiastically of the concept in The Door into Summer (serialized in 1956), was cremated and had his ashes distributed over the Pacific Ocean. Timothy Leary was a long-time cryonics advocate and signed up with a major cryonics provider, but he changed his mind shortly before his death and was not cryopreserved.

See also

References

  1. ↑ McKie, Robin (13 July 2002). "Cold facts about cryonics". The Observer. Retrieved 1 December 2013. Cryonics, which began in the Fifties, is the freezing - usually in liquid nitrogen - of human beings who have been legally declared dead. The aim of this process is to keep such individuals in a state of refrigerated limbo so that it may become possible in the future to resuscitate them, cure them of the condition that killed them, and then restore them to functioning life in an era when medical science has triumphed over the activities of the Banana Reaper.
  2. ↑ Whetstine L, Streat S, Darwin M, Crippen D (2005). "Pro/con ethics debate: When is dead really dead?". Critical Care 9 (6): 538–42. doi:10.1186/cc3894. PMC 1414041. PMID 16356234.
  3. ↑ Merkle RC (September 1992). "The technical feasibility of cryonics". Medical Hypotheses 39 (1): 6–16. doi:10.1016/0306-9877(92)90133-W. PMID 1435395. The extant literature supports but does not prove the hypothesis that cryonics is a feasible method of saving the lives of people who would otherwise certainly die.
  4. ↑ Best BP (April 2008). "Scientific justification of cryonics practice" (PDF). Rejuvenation Research 11 (2): 493–503. doi:10.1089/rej.2008.0661. PMID 18321197.
  5. ↑ Vita-More N., Barranco D. (October 19, 2015). "Persistence of Long-Term Memory in Vitrified and Revived Caenorhabditis elegans". Rejuvenation Research 18 (5): 458–63. doi:10.1089/rej.2014.1636. This is the first evidence of preservation of memory after cryopreservation (vitrification or slow freezing).
  6. ↑ Mayford M, Siegelbaum SA, and Kandel ER (April 10, 2012). "Synapses and Memory Storage" (PDF). Cold Spring Harb Perspect Biol 4: a005751. doi:10.1101/cshperspect.a005751. Procedural and declarative memories differ dramatically. They use a different logic (unconscious vs. conscious recall) and they are stored in different areas of the brain. Nevertheless, these two disparate memory processes share several molecular steps and an overall molecular logic. Both are created in at least two stages: one that does not require the synthesis of new proteins and one that does. In both, short-term memory involves covalent modification of preexisting proteins and changes in the strength of preexisting synaptic connections, whereas long-term memory requires the synthesis of new proteins and the growth of new connections. Moreover, both forms of memory use PKA, mitogen-activated protein kinase (MAPK), CREB-1, and CREB-2 signaling pathways to convert short-term to long-term memory. Finally, both forms appear to use morphological changes at synapses to stabilize long-term memory.
  7. ↑ Guyton, Arthur C. (1986). "The Cerebral Cortex and Intellectual Functions of the Brain". Textbook of Medical Physiology (7th ed.). W. B. Saunders Company. p. 658. ISBN 0-7216-1260-1. We know that secondary memory does not depend on continued activity of the nervous system, because the brain can be totally inactivated by cooling, by general anesthesia, by hypoxia, by ischemia, or by any method, and yet secondary memories that have been previously stored are still retained when the brain becomes active once again. Therefore, secondary memory must result from some actual alterations of the synapses, either physical or chemical.
  8. ↑ Merkle, Ralph (30 April 1994). Cryonics, Cryptography, and Maximum Likelihood Estimation. EXTRO 1. The First Extropy Institute Conference on Transhumanist Thought. Sunnyvale, California. Retrieved 2016-02-14. If we can tell where things should go, then we can in principle (and eventually in practice) restore the patient to full health with their memory and personality intact.
  9. ↑ Donaldson, Thomas (February 1987). "Neural Archeology". Cryonics (Alcor Life Extension Foundation): 24–33. Retrieved 2010-03-13. The really key idea in cryonics is the idea of freezing (or otherwise preserving) people when we don't know if we can ever revive them.... The cryonics proposal is to treat everyone with these conditions as a permanent patient, until means are found to bring them back to life.
  10. ↑ Mazur P (September 1984). "Freezing of living cells: mechanisms and implications". The American Journal of Physiology 247 (3 Pt 1): C125–42. PMID 6383068.
  11. ↑ Mazur P (September 1984). "Freezing of living cells: mechanisms and implications". The American Journal of Physiology 247 (3 Pt 1): C125–42. PMID 6383068.
  12. ↑ Fahy GM, Levy DI, Ali SE (June 1987). "Some Emerging Principles Underlying the Physical Properties, Biological Actions, and Utility of Vitrification Solutions". Cryobiology 24 (3): 196–213. doi:10.1016/0011-2240(87)90023-X. PMID 3595164.
  13. ↑ Smith Audrey U (1957). "Problems in the Resuscitation of Mammals from Body Temperatures Below 0 degrees C". Proceedings of the Royal Society of London. Series B, Biological Sciences 147 (929): 533–44. doi:10.1098/rspb.1957.0077. JSTOR 83173.
  14. ↑ Fahy GM, Wowk B, Wu J (2006). "Cryopreservation of complex systems: the missing link in the regenerative medicine supply chain". Rejuvenation Research 9 (2): 279–91. doi:10.1089/rej.2006.9.279. PMID 16706656.
  15. ↑ Fahy GM, Wowk B, Pagotan R; et al. (July 2009). "Physical and biological aspects of renal vitrification". Organogenesis 5 (3): 167–75. doi:10.4161/org.5.3.9974. PMC 2781097. PMID 20046680.
  16. ↑ Fahy GM, MacFarlane DR, Angell CA, Meryman HT (August 1984). "Vitrification as an approach to cryopreservation". Cryobiology 21 (4): 407–26. doi:10.1016/0011-2240(84)90079-8. PMID 6467964.
  17. ↑ Fahy GM, Wowk B, Wu J; et al. (April 2004). "Cryopreservation of organs by vitrification: perspectives and recent advances". Cryobiology 48 (2): 157–78. doi:10.1016/j.cryobiol.2004.02.002. PMID 15094092.
  18. ↑ Fahy, G; Wowk, B; Wu, J; Phan, J; Rasch, C; Chang, A; Zendejas, E (2005). "Corrigendum to "Cryopreservation of organs by vitrification: perspectives and recent advances" [Cryobiology 48 (2004) 157–178]". Cryobiology 50 (3): 344. doi:10.1016/j.cryobiol.2005.03.002.
  19. ↑ Lemler J, Harris SB, Platt C, Huffman TM (June 2004). "The arrest of biological time as a bridge to engineered negligible senescence". Annals of the New York Academy of Sciences 1019 (1): 559–63. doi:10.1196/annals.1297.104. PMID 15247086.
  20. ↑ Nanofactory Collaboration http://www.MolecularAssembler.com/Nanofactory
  21. ↑ Robert A. Freitas Jr., Nanomedicine, Landes Bioscience; Vol I (1999), Vol IIA (2003) Nanomedicine.com
  22. ↑ de Wolf, Aschwin (2009-01-20). "5 dangerous idea about cryonics". Depressed Metabolism. Retrieved 2010-03-07.
  23. ↑ Legal Protection of Cryonics Patients, Part 1, INSTITUTE FOR EVIDENCE BASED CRYONICS
  24. ↑ Legal Protection of Cryonics Patients, Part 2, INSTITUTE FOR EVIDENCE BASED CRYONICS
  25. ↑ http://www.leparticulier.fr/jcms/c_101664/conseil-d-etat-du-06/01/2006-n-260307-cryogenisation-interdiction
  26. ↑ Chrisafis, Angelique (16 March 2006). "Freezer failure ends couple's hopes of life after death". The Guardian. Retrieved 8 January 2014.
  27. ↑ Whetstine, Leslie; Stephen Streat; Mike Darwin; David Crippen (2005-10-31). Pro/con ethics debate: When is dead really dead?. Critical Care Forum. Retrieved 2006-03-17.
  28. ↑ Fedorov seminar in Moscow, Russia on 25.11.2006
  29. ↑ Curtis Henderson (September–October 1969). "Cryonic Suspension of Ann DeBlasio". Cryonics Reports (Cryonics Society of New York, Inc.) 4 (9–10): 10–15.
  30. ↑ Tandy, Charles. "Charles Tandy, Ph.D.". Retrieved 2008-10-10.
  31. ↑ Charles Tandy (1995). "Cryonic-hibernation in light of the bioethical principles of Beauchamp and Childress". Retrieved 2008-04-01.
  32. ↑ Ettinger, Robert C.W. (1964). The Prospect of Immortality (First ed.). Doubleday. ISBN 0-9743472-3-X.
  33. ↑ Andjus, R.K.; Lovelock, J.E (June 28, 1955). "Reanimation of rats from body temperatures between 0 and 1C by microwave diathermy". The Journal of Physiology 128 (3): 541–546. doi:10.1113/jphysiol.1955.sp005323. PMC 1365902. PMID 13243347.
  34. ↑ "Ev Cooper". cryonet.org. Retrieved 2006-03-17.
  35. ↑ Howley, Kerry (7 July 2010). "Until Cryonics Do Us Part". New York Times Magazine. Retrieved 2 February 2016.
  36. ↑ "Alcor Membership Statistics". www.alcor.org.
  37. ↑ Bob Nelson; Kenneth Bly; Sally Magana (18 March 2014). Freezing People Is (Not) Easy: My Adventures in Cryonics. Lyons Press. pp. 237–. ISBN 978-1-4930-0779-0.
  38. ↑ Stephen Chen. "Cheating death? Elderly writer is the first known Chinese to embrace cryogenics, her head now frozen by lab in Arizona | South China Morning Post". Scmp.com. Retrieved 2015-09-24.
  39. ↑ Kaiser S1, Gross D1, Lohmeier J1, Rosentreter M1, Raschke J2 (2014). "Attitudes and acceptance toward the technology of cryonics in Germany". INTERNATIONAL JOURNAL OF TECHNOLOGY ASSESSMENT IN HEALTH CARE 5 (1): 1–7. doi:10.1017/S0266462313000718. PMID 24499638.
  40. 1 2 3 4 5 6 "The Quick 8: Eight People Who Have Been Cryonically Preserved (and one who wasn't)". Mental Floss. 2009-02-11. Retrieved 2015-09-13.
  41. ↑ Los Angeles Times (4 December 2014). "L. Stephen Coles dies at 73; studied extreme aging in humans". latimes.com.
  42. ↑ "Bitcoin's Earliest Adopter Is Cryonically Freezing His Body to See the Future - WIRED". WIRED.
  43. ↑ "Urban Legends Reference Pages: Disney (Suspended Animation)". snopes.com.
  44. ↑ "The Truth About Walt Disney and Cryogenics". mentalfloss.com.

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