Brain life and brain death: a proposal for a normative agreement.

This paper reviews moral and cultural assessments which led to the definition of brain death and calls for a similar normative consensus regarding the moral recognition and legal protection of embryonal life related to criteria of brain life. This paper differentiates between cortical brain life I, i.e., the first existence of post-mitotic stationary neurons forming the early cortical plate (54th day post conception), and cortical brain life II, i.e., the beginning of cortical neuro-neuronal synapses (after the 70th day p.c.). The latter are preconditional for establishing the communicative network within the cortex and with subcortical structures. The paper conservatively calls for a tentative moral consensus that could recognize brain life I, i.e., the 54th day p.c., as a stage prior to which embryo research generally would be acceptable in accordance with principles similar to those which led to the acceptance of brain death. Other developmental stages such as fertilization, nidation, viability, as well as the 'potentiality' principle are less significant for the moral recognition of early human life.