Alcor Life Extension Foundation (cryonics organization)

Overview of practice

Cryonics is distinct from mainstream medicine: it is speculative and relies on future scientific progress. Alcor provides two main options: whole‑body preservation and neuro (or neuropreservation), in which only the head or brain is preserved. Both approaches aim to minimize ice formation and cellular damage by cooling, chemical perfusion with cryoprotectants, and storage in liquid nitrogen.

Preservation process

The typical sequence begins after legal pronouncement of death. Trained teams stabilize the body, cool it, and maintain circulation and oxygenation as long as possible. A surgical perfusion replaces blood with cryoprotectant to reduce freezing damage, followed by controlled cooling to vitrify tissues, and transfer to long‑term storage in dewars under liquid nitrogen. These steps are designed to preserve fine anatomical structure that proponents argue could be used by future repair technologies.

• Stabilization: emergency cooling and circulatory support.
• Perfusion: replacement of blood with cryoprotectant solutions.
• Vitrification and storage: controlled cooling and long‑term liquid nitrogen storage.

Alcor has preserved a number of people and pets under such protocols and maintains members who arrange funding and legal documentation in advance. Membership typically involves advance directives, contracts, and fees to cover procedures and maintenance.

History, debate and distinctions

Founded in the 1970s, Alcor became one of the best‑known cryonics providers and has been central to discussions about the ethics, legality, and technical feasibility of cryonics. Critics emphasize that revival remains unproven and faces enormous scientific hurdles; supporters argue that current preservation techniques aim to protect the structural information of the brain until repair methods exist. Cryonics should not be confused with cryobiology (scientific study of low‑temperature effects on living tissues) or cryogenics (the physics of very low temperatures).

For more information about Alcor's services and how cryonics is practiced, see the organization's site: Alcor. For discussions of the scientific and ethical issues, see overviews and critiques at resources such as external analyses.