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Can the Clinical Diagnosis of Disorders of Consciousness Avoid Behaviorism?


The “standard approach” in clinical neurology has been accused of suffering from an implicit “behaviorist epistemology” because disorders of consciousness are typically diagnosed on the basis of a lack of behavior. All the gold standard diagnostic assessment programs such as the JFK-Coma Recovery Scale are behavioral in nature insofar as they are expressly looking for behavior or the lack of behavior, either motor behavior or verbal behavior. If the behavior occurs appropriately in response to the command or stimulus then they get points that accumulate towards “normal” consciousness. If no behavior is observable in response to the cue then they don’t get points and are said to have a “disorder of consciousness”.

The problem with this approach is both conceptual and empirical. Conceptually, there is no necessary link between behavior and consciousness because unless you are Gilbert Ryle or Wittgenstein you don’t want to define consciousness in terms of behavior. That is, we don’t want to define “pain” as simply the behavior of your limbs whenever your cells are damaged, or the disposition to say “ouch”. The reason we don’t want to do this is because pain is supposed to be a feeling, painfulness, not a behavior.

Empirically, we know of many cases where behavior and consciousness can be decoupled such as in the total locked-in state where someone’s mind is more-or-less normal but they are completely paralyzed, looking for all intents and purposes like someone in a deep coma or vegetative state yet retaining normal brain function. From the outside they would fail these behavioral assessment techniques yet from the inside have full consciousness. Furthermore we know that in some cases of general anesthesia there can be a complete lack of motor response to stimulation while the person maintains their conscious awareness.

Another problem with the behaviorist epistemology of clinical diagnosis is that the standard assessment scales require a certain level of human expertise in making the diagnostic judgment. Although for most scales there is high inter-rater reliability it nevertheless ultimately comes down to a fallible human making a judgment about someone’s consciousness on the basis of subtle differences between “random” and “meaningful” behavior. A random behavior is just that: a random, reflexive movement that signifies no higher purpose or goal. But if I ask someone to squeeze my hand and they squeeze it, this is a meaningful sign because it suggests that they can listen to language and translate a verbal command to a willed response. But what if the verbal command to squeeze just triggers an unconscious response to squeeze? Sure, it’s possible. No one should rule it out. But what if they do it 5 times in a row? Or what if I say “don’t squeeze my hand” and they don’t squeeze it? Now we are getting into what clinicians call “unambiguous signs of consciousness” because the behavior is expressive of a meaningful purpose and shows what they call “contingency”, which is just another way of saying “appropriate”.

But what does it mean for a behavior to really be meaningful? Just that there is a goal-structure behind it? Or that it is willed? Again, we don’t want to define “meaning” or “appropriateness” in terms of outward behavior because when you are sleepwalking your behavior is goal-structured yet you are not conscious. Or consider the case of automatic writing. In automatic writing one of your hands is capable of having a written conversation and writing meaningful linguistic statements without “you” being in control at all. So clearly there is a possible dissociation between “meaningful” behavior and consciousness. All we can say is that for normal people in normal circumstances meaningful behavior is a good indicator of normal consciousness. But notice how vacuous that statement is. It tells us nothing about the hard cases. 

So in a nutshell the diagnosis of disorders of consciousness has an inescapable element of human subjectivity in it. Which is precisely why researchers are trying to move to brain-based diagnostic tools such as fMRI or EEG, which are supposed to be more “objective” because they skip right over the question of meaningful behavior and look at the “source” of the behavior: the brain itself. But I want to argue such measures can never bypass the subjectivity of diagnosis without going full behaviorist. The reason why brain-based measures of disorders of consciousness are behaviorist is simply because you are looking at the behavior of neurons. You can’t see the “feelings” of neurons from a brain scanner anymore than you can see the “feeling” of pain from watching someone’s limb move. Looking at the brain does not grant you special powers to see consciousness more directly. It is still an indirect measure of consciousness and it will always require the human judgment of the clinician to say “Ok, this brain activity is going to count as a measure towards “normal” consciousness”. It might be slightly more objective but it will never be any less subjective unless you want to define normal consciousness in terms of neural behavior. But how is that any different from standard behaviorism? The only difference is that we are relying on the assumption that neural behavior is the substrate of consciousness. This might be true from a metaphysical perspective. But it’s no help in the epistemology of diagnosis because as an outside observer you don’t see the consciousness. You just see the squishy brain or some representation on a computer screen. I believe there is a circularity here that cannot be escaped but I won’t go into it here (I talk about it in this post).


Filed under Consciousness, Philosophy of science, Psychology, Uncategorized

Medically Incompetent Doctors Should Not Diagnose Disorders of Consciousness: The Sad Case of Haleigh Poutre

Politics, ideologies, or other motivations can similarly skew medical findings in the other direction, as the botched case of Haleigh Poutre reveals. This Massachusetts case, which followed on the heels of Terri’s death, involved an eleven-year-old girl who had been the subject of repeated battering and had entered what doctors believed to be a vegetative state. In fact only eight days after she had entered the hospital in a condition of unconsciousness, her doctors declared her vegetative state to be permanent. The state of Massachusetts, through its Department of Social Services, won temporary custody of Haleigh and sought to remove her from all life support. Although not the explicit motive for the state’s petition, if Haleigh died, her step-father, accused of beating Haleigh, could have been charged with murder. The department’s petition was successful in lower court and affirmed by the state supreme court. But the day after the court’s decision, it became apparent that Haleigh was not permanently unconscious; in fact, she was not even unconscious at that moment! Two years later, she has recovered some speech and also communicates through a keyboard; ABC News reported that she might be well enough to testify against her stepfather.

Louis Shephard, It it happened to me: making life and death decisions after Terri Schiavo, p. 33

What makes the bolded sentence so outrageous is that according to conventional medical guidelines a “persistent” vegetative state should be declared 1 month after injury and a “permanent*” vegetative state should be declared 3 months after non-traumatic brain damage and 12 months after traumatic brain damage.

*Many experts recommend abandoning the term “permanent” because it implies a greater degree of epistemic certainty than is warranted. What “PVS” really means is that there is the odds are stacked against recovery because of statistical patterns of patients with similar brain injuries. However, the fact that most DOC patients recover 3-12 months after injury indicates that the most accurate approach is merely to describe the VS state and then specify how long they have been in the state rather than trying to categorically predict their chances of recovery.

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Filed under Consciousness, Neuroethics