Cryonics

Technicians prepare a body for cryopreservation in 1985.

Cryonics (from Greek κρύος kryos meaning 'cold') is the low-temperature preservation (usually at −196 °C) of a human corpse, with the hope that resuscitation and restoration to life and full health may be possible in the future.[1] Cryopreservation of humans is not reversible with present technology; cryonicists hope that medical advances will someday allow cryopreserved bodies to be revived.[2]

It is unlikely that the mind could be restored after current methods of cryonics which involve vitrification because of damage to the brain, including to neural networks. [3]

Cryonics is regarded with skepticism within the mainstream scientific community and is not part of normal medical practice. It is not known if it will ever be possible to revive a cryopreserved human cadaver. Cryonics depends on beliefs that the frozen body has not experienced information-theoretic death. Such views are at the speculative edge of science.[4]

Cryonics procedures can only begin after clinical death, and cryonics "patients" are legally dead. Cryonics procedures ideally begin within minutes of death,[5] and use cryoprotectants to prevent ice formation during cryopreservation.[6] The first corpse to be cryopreserved was that of Dr. James Bedford in 1967.[7] As of 2014, about 250 bodies were cryopreserved in the United States, and 1,500 people had made arrangements for cryopreservation after their legal death.[8]

Concept

Cryonic proponents go further than the mainstream consensus in asserting that the brain does not have to be continuously active to survive or retain memory. Cryonics controversially asserts that a human survives even within an inactive brain that has been badly damaged, provided that original encoding of memory and personality can, in theory, be adequately inferred and reconstituted from structure that remains.[8][9] Cryonicists argue that as long as brain structure remains intact, there is no fundamental barrier, given our current understanding of physical law, to recovering its information content. The cryonics argument that death does not occur as long as brain structure remains intact and theoretically repairable has received some mainstream medical discussion in the context of the ethical concept of brain death and organ donation.[10][11][12]

Cryonics uses temperatures below −130 °C, called cryopreservation, in an attempt to preserve enough brain information to permit future revival of the cryopreserved person. Cryopreservation may be accomplished by freezing, freezing with cryoprotectant to reduce ice damage, or by vitrification to avoid ice damage. Even using the best methods, cryopreservation of whole bodies or brains is very damaging and irreversible with current technology.

Cryonics requires future technology to repair or regenerate tissue that is diseased, damaged, or missing. Brain repairs in particular will require analysis at the molecular level. This far-future technology is usually assumed to be nanomedicine based on molecular nanotechnology.[13][14][15] Biological repair methods[16] or mind uploading[17] have also been proposed.

Other Languages
български: Крионика
català: Criònica
čeština: Kryonika
dansk: Kryonik
Deutsch: Kryonik
eesti: Krüoonika
Ελληνικά: Κρυογονική
español: Criónica
Esperanto: Krioniko
euskara: Krionika
فارسی: سرمازیستی
français: Cryonie
galego: Criónica
italiano: Crionica
עברית: קריוניקה
македонски: Крионика
Mirandés: Criónica
Nederlands: Cryonisme
polski: Krionika
português: Criônica
română: Crionică
русский: Крионика
shqip: Krionika
Simple English: Cryonics
slovenčina: Kryonika
српски / srpski: Крионика
suomi: Kryoniikka
svenska: Kryonik
Türkçe: Cryonics
українська: Кріоніка
Tiếng Việt: Cryonics