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Wednesday, December 05, 2007

ADHD and Evolution

At this link there is an interesting critical review I came across between an author and one of his graduate students. The student's review amounts to an ad hominem fallacy against the author but it also brings out the difference between this author and a rival theory from another author.

The subject in question is ADHD, attention deficit/hyperactivity disorder. Both authors agree that there is such an issue in one sense, namely that individuals with ADHD are significantly neurophysiologically different from individuals without it. However, Hartman (represented by the the student) is a relativist about the evaluation of the condition and Barkley (represented by his book) is not.

Barkley's book is based on original systematic research as well as a synthesizing of the results of all previous research. It offers a new theory of ADHD which has fruitful suggestions for all sorts of new questions for further research, for reforms of diagnostic criteria, and for therapeutic intervention, both positively and negatively.

A normal human brain has the ability not only to perceive objects but to see them oriented to one another in 3-dimensional space. This ability enables the human subject to move around effectively in the world from place to place and to form successful executive performances with respect to location. By the same token, a normal human brain also has the ability to orient events (including past and hypothetical future events) in time -- it can "see into the fourth dimension". This allows the human subject to navigate effectively and satisfy executive functions with respect to time. The ability to perform both functions is grounded in the structure of the frontal cortex of the brain.

According to Barkley, the person with ADHD is "time blind". They do not have this capacity to orient events in time that normal humans have because they have an abnormal frontal cortex. Consequently, they are forced to live always in the immediate "now" moment. It is this that explains the attention and impulsively problems, which on this view are really secondary to the real problem. It also explains chronic nature of ADHD, why it persists through life, why it can only be directly effected by medication, and why it cannot be cured by cognitive behavioral therapy, although it can be facilitated by constant, continuous behavioral scheduling. People with ADHD are like diabetics with respect to the intractability of their condition. There is no cure for ADHD.

Hartman's theory, on the other hand, suggests that the best way to make sense of ADHD is through evolutionary anthropology. At one time the human race was divided into "hunters" and "farmers". In the course of time, the farmers were more evolutionarily fit and displaced the hunters in the hegemony of society but descendants of the hunters remain in society albeit marginalized. ADHD persons are descendants of the hunters and are equipped differently from them. As hunters, their condition is only "abnormal" in virtue of the poor fit it has with respect to the dominant farmer based society.

It is no doubt the case that both author's hold to the theory of evolution, but Hartman relies on on it more conspicuously than Barkley. Barkley's view is more Aristotelian in suggesting that ADHD persons fail to have a property priorly proper to their type. It is not bad for a goat not to be able to talk since goats don't talk anyway. But it would be bad if a human being couldn't talk since talking is part of the natural powers of a human being. By the same token, it is not good for human beings to be time blind and this is not just true relative to a dominant culture, there is a fact of the matter.

Barkley is an expert researcher. I've looked at Hartman's book and it does not have the same evidential standards as Barkley. But aside from the evidential question, there is the specter of a political side to this debate. A motive you could possibly have for accepting Hartman's relativistic account is that, in a sense, in "normalizes" ADHD. "I'm a hunter and you're a farmer. We're just different." Since ADHD is often attended with morbid affect and low-self esteem, you can see how a morbid person would prefer this justification of his character. On Barkley's account, it seems like there is something necessarily inferior about the ADHD person (which seems to be Barkley's own view if the students remarks about his classroom behavior are to be believed). It may suggest that the best thing might be to round up all the ADHD people and lock them away.

But in Barkley's own book, ADHD is a condition that the person could not choose to not have and cannot help but place the burden that he does on society. Thus, such a person should be treated with compassion rather than derision. Given how "we" could not have developed as much as we have without the faculty of time sight, the lack of such a faculty must be a grievous burden on the well intended person with ADHD both for his own sake and also for the good he would do in society. Such a picture inspires our pity and mercy. There is no occasion for mercy if Hartman is right.

As a person who takes himself to have ADHD and who is also a Christian, my inclination is to side with Barkley. For starters, Barkley's work amounts to an argument in behalf of the objectivity of human nature and an objective order of natural based values, which is consistent with a teleological argument for God's existence from the existence of natural objective "design plans" such as humans and final causes. That is, he gives us reasons for believing in a teleological universe. From the prudential side, however, I think the student should consider that in this case if everything is normal, nothing is. If one were to embrace Hartman's view because it gives an account where there is no abnormal condition and thus no reason to feel bad about oneself, then one would be throwing out a very important baby with the bath water, the idea that there is such a thing as true value and a meaning to life. The attractiveness of the hunter/farmer distinction looks appealing because it seems to describe the ADHD person's place in the Great Human Republic as "hunter", but the view actually denies the existence of the Great Human Republic altogether.

It is admittedly painful for an ADHD person to confront all the implications of the Barkley view, with the realization that he is much more like an animal than a person in this respect and that the fulfillment of human potential is something outside of his power altogether. He is bound to experience that as if it were a kind of loss of something he never really had in the first place. It would be better to by literally blind but still have time sight then it would be to have ADHD and see, it seems to me. Still, I think Barkley is the best explanation and the one that it would be the most wise to accept.

It would take a real miracle to heal ADHD, just like the man born blind, the sort of thing I don't expect to see until Jesus returns. In the mean time, Paul's remarks about the thorn in his side seem to apply. It certainly also effects my judgment of sin and responsibility.