Jones D G
University of Otago, Dunedin, New Zealand.
J Med Ethics. 1998 Aug;24(4):237-42. doi: 10.1136/jme.24.4.237.
The possible symmetry between the concepts of brain death and brain birth (life) is explored. Since the symmetry argument has tended to overlook the most appropriate definition of brain death, the fundamental concepts of whole brain death and higher brain death are assessed. In this way, a context is provided for a discussion of brain birth. Different writers have placed brain birth at numerous points: 25-40 days, eight weeks, 22-24 weeks, and 32-36 weeks gestation. For others, the concept itself is open to question. Apart from this, it needs to be asked whether a unitary concept is an oversimplification. The merits of defining two stages of brain birth, to parallel the two definitions of brain death, are discussed. An attempt is then made to map these various stages of brain birth and brain death onto a developmental continuum. Although the results hold biological interest, their ethical significance is less evident. Development and degeneration are not interchangeable, and definitions of death apply specifically to those who are dying, not those who are developing. I conclude that while a dual concept of brain death has proved helpful, a dual concept of brain birth still has problems, and the underlying concept of brain birth itself continues to be elusive.
本文探讨了脑死亡和脑诞生（生命）概念之间可能存在的对称性。由于对称性观点往往忽视了脑死亡最恰当的定义，因此对全脑死亡和高级脑死亡的基本概念进行了评估。以此为基础，为讨论脑诞生提供了背景。不同的作者将脑诞生的时间点定在多处：妊娠25 - 40天、八周、22 - 24周以及32 - 36周。对另一些人来说，这个概念本身就值得质疑。除此之外，还需追问单一概念是否过于简化。文中讨论了定义脑诞生两个阶段以对应脑死亡两种定义的优点。接着尝试将脑诞生和脑死亡的这些不同阶段映射到一个发育连续体上。尽管这些结果具有生物学意义，但其伦理意义却不那么明显。发育和衰退不可互换，死亡的定义专门适用于濒死之人，而非发育中的人。我的结论是，虽然脑死亡的双重概念已被证明是有用的，但脑诞生的双重概念仍存在问题，而且脑诞生本身的基本概念仍然难以捉摸。
