RESUMEN
Neurodegenerative diseases, of which the Alzheimer's disease, are more and more frequently the object of researches and new experiments. One wishes these experiments to be promising. Experiment with persons affected by a degenerative disease can begin at a moment when the subject is capable, and can be pursued beyond his incapacity. Law authorizes that a person of full age incapable of giving consent be subject of experiment. On the other hand, from the report of the incapacity, consent has to come from the legal representative: the mandatary, tutor or curator. The mandate given in anticipation of the mandator's incapacity empowers another person (the mandatary) to represent her. The use of this mandate confines the inconveniences of the mandator's incapacity to an interruption of the experiment for a duration of some weeks.
