Terri Schiavo

A “vegetative state” is a state in an individual allegedly lacks conscious awareness, though he breathes on his own and has sleep-wake cycles. After one year in a vegetative state, the patient is considered to be in a permanent vegetative state (PVS), lacking any possibility of regaining consciousness. For years, many neurologists have blithely stated that individuals in a PVS lack all conscious awareness. These claims were (and continue to be) made in spite of a fundamental ignorance of the nature of consciousness generation in the brain (as David W. Evans, M.D., has long pointed out [Evans, 2000]). Many advocates of so-called “higher brain death” have argued that such patients should be declared dead and used as organ donors. Similar claims have been made concerning anencephalic infants (infants who have a brainstem, but lack a cerebrum and thus lack a cerebral cortex). If such patients are permanently unconscious, the argument goes, they lack personhood and thus are proper candidates for organ donation.

Although a good philosophical argument can be made against the consciousness theory of personhood (the roots of which lie in Descartes and Locke), a strong empirical case can be made that some (perhaps most) of patients diagnosed with a PVS are conscious. First, in the case of anencephalic infants, Alan Shewmon, M.D., a pediatric neurologist who teaches at the UCLA School of Medicine, studied three children with either no cerebral cortex or an almost nonexistent cerebral cortex. Shewmon’s resulting article (co-written with Gregory A. Holmes, M.D. and Paul A. Byrne, M.D. [Shewmon, Holmes, and Byrne, 1999]) notes that these children, with ages ranging from 5-17, “possessed discriminative awareness, eg, distinguishing familiar from unfamiliar people and environments, social interaction, functional vision orienting, musical preference, appropriate affective responses, and associative learning.” (p. 364). Failure to recognize the results of neuroplasticity (parts of the brain taking over some functions of the missing parts) was due to doctors assuming that such infants could not be conscious, and therefore, these infants were allowed to die.

Neurologists have also been overly quick to deny the possibility for consciousness for individuals in a PVS. As early as 1996, there was a case study published in the prestigious New England Journal of Medicine concerning a woman diagnosed as being in a PVS who began to recover after fifteen months. (Childs and Mercer, 1996). She recovered to the point of being able to follow conversations and even speak individual words or phrases. Though severely disabled, she was clearly conscious. Another 1996 study from the United Kingdom (Andrews, et al., 1996) revealed that 43% of patients in a disability hospital who had been diagnosed with a PVS were, in fact, misdiagnosed. Many of these misdiagnosed patients are actually in a “minimally conscious state.” (Giacino, et al., 2002).

The most dramatic case of consciousness in an individual diagnosed with a PVS is that of a Belgian man, Rom Houben. But new technology revealed that his brain has been functioning at a level consistent with consciousness. A trained therapist, Linda Wouters, learned to communicate with Mr. Houben by feeling pressure from his fingers and using a keyboard. Mr. Houben has apparently been conscious the entire twenty-three years of his supposed PVS. (Casert, 2009). Despite such strong evidence, University of Pennsylvania bioethicist Arthur Caplan questioned whether Mr. Houben is really communicating. Caplan claims that the movements of his hand on a keyboard are really the work of therapist Linda Wouters. “That’s called facilitated communication. That is Ouija board stuff. It’s been discredited time and time again. When people look at it, it’s usually the person doing the pointing who’s doing the messages, not the person they claim to be helping.” (Casert, 2009). The magician and consummate skeptic James Randi has also joined in the criticism.

But Mr. Houben’s doctor, Stephen Laureys, insists that Mr. Houben has been communicating, noting that Houben has made progress over time in his ability to communicate (Casert [2], 2009). Laureys, in his own study of patients diagnosed with PVS, has confirmed the 40% misdiagnosis rate. (Connolly, 2009). But even in other cases, the old adage, of which Shewmon is fond, follows: “Absence of evidence is not evidence of absence.” That is, absence of evidence of consciousness in a PVS patient is not evidence of the absence of consciousness.

As far as Professor Caplan’s arguments go, he has not, as far as I am aware, seen Mr. Houben. He automatically assumes that Linda Wouters is moving Mr. Houben’s fingers to the right letters on the keyboard. He assumes that a man with Mr. Houben’s degree of brain damage could not communicate using the complex sentences he uses. This simply begs the question of Mr. Houben’s actual level of consciousness. Basically Professor Caplan’s argument amounts to: “I know that Mr. Houben cannot be conscious; therefore he cannot be conscious.” Caplan assumes that scientists know beyond a reasonable doubt the level of brain activity necessary to sustain consciousness and to sustain complex cognitive states. Yet study after study and case after case raise questions about this claim. Perhaps scientists are more ignorant about such matters than Professor Caplan believes. I suppose that Mr. Houben would have to speak using his (Houben’s) own voice to Professor Caplan for him to believe that Mr. Houben is conscious. But if that happened, perhaps I assume too much: Professor Caplan could still insist that a ventriloquist is faking Mr. Houben’s voice. One wonders about the falsifiability of Professor Caplan’s position.

If many PVS patients show evidence of consciousness, and many of the remainder might still be conscious, it is wrong to consider such patients “dead,” and is doubly wrong to consider changing the law to allow the harvesting of their organs. It is possible that the real source of the fear from Mr. Houben’s case is that more severe forms of brain pathology, such as so-called “whole-brain death” (the U.S. standard) and “brainstem death” (the UK standard) may also be disqualified due to the possibility that there could be residual consciousness in these patients. If such patients could be conscious, then the entire basis for harvesting organs from “brain dead” individuals would be destroyed. Thus, bioethicists may want to head off this chain of reasoning “at the pass” by denying that a long-term PVS patient, such as Mr. Houben, could be conscious and communicating.

REFERENCES

Andrews K, Murphy L, Munday R, Littlewood C (1996). Misdiagnosis of the vegetative state: retrospective study in a rehabilitation unit BMJ 313:13-16 (6 July).

Casert R (2009). Comatose for 23 years, Belgian feels reborn. The Associated Press, 25 November.

Casert, R. [2] (2009). Doc takes on coma skeptics. The Associated Press, 27 November.

Childs NL, Mercer WN (1996). Late improvement in consciousness after post-traumatic vegetative state. NEJM 334:24-25.

Connolly K (2009). Car crash victim trapped in ‘coma’ for 23 years was conscious. At: guardian.co.uk, 23 November 2009. Accessed 23 November 2009.

Evans DW (2000). The demise of ‘brain death’ in Britain. In: Potts M, Byrne PA, Nilges RG (eds.), Beyond Brain Death: The Case Against Brain-Based Criteria for Human Death. Dordrecht, The Netherlands: Kluwer Academic Publishers.

Giacino JT, Ashwal S, Childs N., et al. (2002). The minimally conscious state: Definition and diagnostic criteria. Neurology 58:349-353 (12 February).

Shewmon DA, Holmes GL, Byrne PA (1999). Consciousness in congenitally decorticated children: developmental vegetative state as self-fulfilling prophecy. Dev Med Child Neurol 41:364-374.

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