Beyond the Twilight Zone: A Comparative History of Brain Death Policies in Japan and the United States

Hiroyuki Nagai
Volume 4 Issue 1 Pages 1-14
First Published: April 2, 2021



In Japan and the United States, brain death policy development has resulted in a situation where two opposing positions co-exist regarding the notion that “brain death is human death.” Although discussions on this topic have only taken shape in the United States this century, similar discussions were already underway in twentieth-century Japan. This paper explores how public debates in the United States caught up with those in Japan. Comparative analysis of the processes leading to the development of brain death criteria reveals that, in Japan, the creation of medical evidence-based criteria occurred in a smooth, sequential manner—first addressing cases with a short “alpha period” (i.e., the period from brain death leading to cardiac death), with many brain death cases defined as those caused by primary lesions, unlike in the United States where lesions (i.e., multisystemic disorders) were deemed responsible for a majority of brain death cases. By clarifying the historical context, this study shows how this difference in definition has led to the co-existence of two opposing policies. In Japan, various technological developments extended the “alpha period” by the 1990s, while controlling it with appropriate ethical considerations. This period—referred to as the “twilight zone”—was never widely accepted in the United States, but Japanese attempts to extend the “alpha period” were incorporated into bioethics commission reports in the 2000s.


Key words

Bioethics policymaking, Brain death, Comparative history, Harvard Criteria, Takeuchi Criteria