Distinguish Patients in a Vegetative State from the Minimally Conscious state: moral and legal dilemmas

research done using current neuroimaging techniques-specifically, positron emission tomography (pet) and functional magnetic resonance imaging (functional mri)-have provided evidence that vegetative patients may have fragments of consciousness. these findings make all the more urgent the familiar moral and legal dilemmas arising in connection with persons in these "reduced" states, because in debating whether these persons have a will, we have to take into account the possibility that they may have "glimpses of consciousness". in other words, we have to revisit that principle in light of scientific advances enabling us to more accurately detect signs that a patient is expressing a will to be taken off life support.