cryonics

cryonics, the practice of freezing an individual who has died, with the object of reviving the individual sometime in the future. The word cryonics is derived from the Greek krýos, meaning “icy cold.” For the production of low-temperature phenomena, see cryogenics.

Cryonic preservation can be performed only after an individual has been declared legally dead. The process is initiated shortly after death, the body being packed in ice and shipped to a cryonics facility. There the blood is drained from the body and is replaced with antifreeze and organ-preserving compounds known as cryoprotective agents. In this vitrified state, the body is placed in a chamber filled with liquid nitrogen, where it will theoretically stay preserved at -196 °C until scientists are able to find a way to resuscitate the body in the future.

Cryonic preservation is expensive, full-body preservation potentially costing hundreds of thousands of dollars. Nonetheless, by 2023 about 500 individuals had been cryonically preserved, the majority of them in the United States. Dozens of pets had also been preserved. Some individuals chose to have their entire bodies frozen, whereas others wanted only their heads preserved, a process known as neuropreservation. The option to cryonically preserve only a person’s head is based on the belief by many cryonics adherents that cryonically preserved personalities may one day be downloaded into robot bodies or be transferred into entirely new bodies grown from stem cells.

The concept of cryonic preservation was popularized in The Prospect of Immortality, a book by Robert Ettinger that was initially released in 1962 and formally published in 1964. Ettinger subsequently became known as the father of cryonics. His body was cryonically preserved upon his death in 2011 and was stored at the Cryonics Institute in Clinton Township, Michigan. The first human to be cryonically preserved was James Bedford. On January 12, 1967, Bedford died from liver cancer that had metastasized to his lungs. Bedford died before all the arrangements for his cryonic preservation could be completed. As a result, his body was injected with cryoprotective agents without first draining his blood, and his body was then packed in dry ice. Bedford’s body was later immersed in liquid nitrogen and transferred from one facility to another, finally ending up at the Alcor Life Extension Foundation in Scottsdale, Arizona.