Last week I attended a conference on the science of consciousness in Helsinki. While there, I attended a very interesting session on the Minimally Conscious State (MCS). This is a state that follows severe brain damage. Those diagnosed as MCS are thought to have some kind of conscious mental life, unlike those in Vegetative State. If that is right – so say many bioethicists and scientists – then the moral implications are profound. But what kind of conscious mental life is a minimally conscious mental life? What kind of evidence can we muster for an answer to this question? And what is the moral significance of whatever answer we favor? One takeaway from the session (for me, at least): it’s complicated.
In his contribution to the session, the philosopher Tim Bayne pointed out that there are various routes to a diagnosis of MCS. Patients are put through a series of tests and receive a score that sums performance in a series of categories – auditory function, visual function, motor function, verbal function, communication, and arousal are measured. In order to be diagnosed as in the MCS, a patient must receive a high enough score on one of the scales. For example, looking solely at the visual function scale, a patient must exhibit fixation as opposed to visual startle.
Visual startle is tested by presenting a ‘visual threat’ – in this case, passing a finger 1 inch in front of the patient’s eye. Visual startle is demonstrated when the patient’s eyelid ‘flutters’ or when a blink follows, on at least 2 out of 4 trials.
The views, opinions and positions expressed by these authors and blogs are theirs and do not necessarily represent that of the Bioethics Research Library and Kennedy Institute of Ethics or Georgetown University.