In most developed countries, brain death is the ultimate criterion that life, as we understand it, has irrevocably departed the body. Cardiac arrest, once considered the standard, is often reversible. Recognizing brain death is not simple, and often involves meeting both legal and medical criteria.
- Eelco F.M. Wijdicks, Panayiotis N. Varelas, Gary S. Gronseth, et al. (28 February 2011), "Evidence-based guideline update: Determining brain death in adults; Report of the Quality Standards Subcommittee of the American Academy of Neurology", Neurology 74: 1911, DOI:10.1212/WNL.0b013e3181e242a8 DOI 10.1212/WNL.0b013e3181e242a8