Information-theoretic death

From Wikipedia, the free encyclopedia
Jump to: navigation, search

The term Information-theoretic death relates to physical damage to the brain and the loss of information. It is the destruction of the information within a human brain to such an extent that recovery of the original person is theoretically impossible by any physical means. The concept of information-theoretic death emerged in the 1990s as a response to the progress of medical technology since conditions previously considered as death, such as cardiac arrest, are now reversible, so they can no longer define death.[1] The term alludes to information theory in mathematics.

The term information-theoretic death is intended to mean death that is absolutely irreversible by any technology, as distinct from clinical death and legal death, which denote limitations to contextually-available medical care rather than the true theoretical limits of survival. In particular, the prospect of brain repair using molecular nanotechnology raises the possibility that medicine might someday be able to resuscitate patients even hours after the heart stops.

The paper Molecular Repair of the Brain by Ralph Merkle defined information-theoretic death as follows:[2]

A person is dead according to the information-theoretic criterion if their memories, personality, hopes, dreams, etc. have been destroyed in the information-theoretic sense. That is, if the structures in the brain that encode memory and personality have been so disrupted that it is no longer possible in principle to restore them to an appropriate functional state, then the person is dead. If the structures that encode memory and personality are sufficiently intact that inference of the memory and personality are feasible in principle, and therefore restoration to an appropriate functional state is likewise feasible in principle, then the person is not dead.

The exact timing of information-theoretic death is currently unknown. It has been suggested[3] [4] to occur gradually after many hours of clinical death at room temperature as the brain undergoes autolysis. It may also occur more rapidly if there is no blood flow to the brain during life support, leading to the decomposition stage of brain death, or during the progression of degenerative brain diseases that cause extensive loss of brain structure.

The use of information-theoretic criteria has formed the basis of ethical arguments that state that cryonics is an attempt to save lives rather than being an interment method for the dead. In contrast, if cryonics cannot be applied before information-theoretic death occurs, or if the cryopreservation procedure itself causes information-theoretic death, then cryonics is not feasible. Exactly when complete and total information-theoretic death might occur with respect to different types of preservation and decomposition might also be relevant to the speculative field of mind uploading.

Although the idea of information-theoretic death was first introduced in the context of cryonics,[5] the term has since been used in medical journals discussing issues surrounding brain death[6][7][8] with the same meaning first defined by Merkle.

References[edit]

  1. ^ IMR (International Medical Rights)
  2. ^ Merkle, Ralph (January–April 1994), "Molecular Repair of the Brain", Cryonics, retrieved 2014-12-27 – via Alcor library online 
  3. ^ Merkle, R (1992). "The technical feasibility of cryonics". Medical Hypotheses (Elsevier) 39 (1): 6–16. doi:10.1016/0306-9877(92)90133-W. PMID 1435395. 
  4. ^ Wowk, B (2014). "The future of death". Journal of Critical Care (Elsevier) 29 (6): 1111–1113. doi:10.1016/j.jcrc.2014.08.006. PMID 25194588. 
  5. ^ Merkle, R (1992). "The technical feasibility of cryonics". Medical Hypotheses (Elsevier) 39 (1): 6–16. doi:10.1016/0306-9877(92)90133-W. PMID 1435395. 
  6. ^ Whetstine, L; Streat, S; Darwin, M; Crippen, D (2005). "Pro/con ethics debate: When is dead really dead?". Critical Care (BioMed Central) 9 (6): 538–542. doi:10.1186/cc3894. PMID 16356234. 
  7. ^ Crippen, DW; Whetstine, L (2007). "Ethics review: Dark angels – the problem of death in intensive care". Critical Care (BioMed Central) 11 (1): 202. doi:10.1186/cc5138. PMID 17254317. 
  8. ^ Wowk, B (2014). "The future of death". Journal of Critical Care (Elsevier) 29 (6): 1111–1113. doi:10.1016/j.jcrc.2014.08.006. PMID 25194588. 

External links[edit]