Yes. No brain function, no life.
Is a brain-dead person on life-support with a beating heart or functional kidneys considered "alive"?
In a recent essay for First Things, Maureen L. Condic, PhD, Assistant professor of Neurobiology and Anatomy at the University of Utah, presents a convincing argument for meaning of the death protocol (used when organ harvesting is anticipated) to also be used when contemplating prenatal life. She has stated accurately that, the loss of integrated bodily function, not the loss of higher mental ability, is the defining legal characteristic of death.
That is an accurate reading of the protocol but there is confusion by some regarding this protocol because it addresses brain death, yet it doesnt refer to mere loss of thinking ability. It should not be assumed that being alive is solely a function of higher brain functioning, or even dependent upon the organ called brain.
To paraphrase Dr. Condics assertion: to be alive as an ORGANISM, the organism is functioning as an integrated whole, rather than life being defined solely from an organ (a form within the organism) that functions to make the whole organism work. The one organ defines alive notion was the perspective years ago. People focused upon one organ, when the heart was the center of function, before organ harvesting became a reality; when the heart stopped beating, the person was thought to be dead, thought to be no longer an integrated whole organism. Today, doctors routinely stop and start the heart, keeping the patient viable as an integrated whole via artificial heart and lungs.
A person in an unrecoverable coma or vegetative state has no higher brain function, yet their body continues to function as an integrated whole. As Dr. Condic puts it, Although such patients are clearly in a lamentable medical state, they are also clearly alive, [so] converting such patients into corpses requires some form of euthanasia.
Human life is defined by the ability to function as an integrated whole, not by mere presence of living human cells.