Monday, February 26, 2018

Sorting Souls with fMRI


In the March issue of Scientific American, brain-imaging expert John Gabrieli says that we can now use functional magnetic-resonance-imaging (fMRI) technology to predict whether depressed patients will benefit from certain therapies, whether smokers will be able to quit, and whether criminals will land back in jail soon.  But he leaves unanswered some questions he raises—namely, if we find that we can reliably obtain this kind of information, what should we do with it?

First, a brief explanation of what fMRI does.  Using basically the same giant-liquid-helium-cooled-magnet MRI technology that hospitals use, fMRI detects changes in blood flow in the brain as certain regions become more active while the patient is thinking about or viewing different things.  For example, my niece is now a psychology postdoc in Omaha, Nebraska, doing research on troubled adolescents by putting them in an fMRI machine and having them play specially designed video games, and watching what goes on in their brains as they play.  According to Gabrieli, who is at MIT and presumably knows what he's talking about, fMRI studies have been able to discriminate between depressed patients who will benefit from cognitive behavior therapy, and those who won't.  He is somewhat short on statistics of exactly how accurate the predictions are, and admits that the technology has a way to go before it's as reliable as, say, a pregnancy test kit. 

But just for the sake of argument, suppose tomorrow we had a 95%-accurate technology that was cheap enough to be widely used (neither of which describes fMRI yet), and could tell us ahead of time the likelihood that a convicted criminal would be back in jail in five years.  What could we do with the information?

Given that one purpose of imprisonment is to protect the public, you could argue that those criminals who are very likely to commit more crimes should not be let out on the streets, at least until their fMRI scans improve.  And those whose fMRI scans showed that they were at very little risk of committing more crimes might have their sentences curtailed, or maybe we should just release them right away. 

Say you are a member of a parole board, trying to decide which prisoners should be granted parole.  Wouldn't you be glad to have fMRI data on the prisoners that was shown scientifically to be pretty accurate, and wouldn't you feel more confident in your decisions if you based them partly or even mostly on the fMRI predictions?  I think I would.

But what does this look like from the prisoner's point of view?  Suppose you led a life of crime and didn't change your ways until you landed in jail, when you came to yourself and turned over a new leaf.  (It happens.)  You present your sterling behavior record since then to the parole board, but then they make you stick your head in a machine, and the machine says your anterior cingulate cortex is just as unreformed as ever, and the board denies your request for parole.  Wouldn't you feel unfairly treated?  I think I would.

What's going on here is a conflict between two anthropologies, or models of what a human being is.  The psychologists who use fMRI studies to predict behavior emphasize that people are physical structures that work in certain ways.  And they have found strong correlations between certain brain activities and subsequent behavior.  They say, "People with this kind of fMRI profile tend to do that," and they have statistics to back up their claims.  While they admit there are such things as ethical considerations, they spend most of their time thinking of their subjects as elaborate machines, and trying to figure out how the machine works based on what they can see it doing in an fMRI scan.  If you asked Dr. Gabrieli if he believes in free will, he might laugh, or say yes or no, but he would probably regard the question as irrelevant to what he's doing.

The question of free will is crucial to a different model of the human being, the one that claims people have rational souls.  From William James on, the discipline of psychology has tended to dispense with the concept of the soul, but that doesn't change the fact that each of us has one.  I once knew a man who was a former drug user.  Then he became a Christian, settled down, started his own small business, married, and was leading a stable upstanding life the last time I heard of him.  I don't know this for a fact, but I suspect his anterior cingulate cortex would send an fMRI machine off the charts.  Nevertheless, by what psychologists might call strength of will, and by what believers would call the grace of God, he overcame his almost irrepressible desires to do bad things and developed new good habits. 

We once thought it was reasonable to discriminate against people simply because of the color of their skin.  Black people couldn't intermarry with white people, couldn't hold certain jobs, and were (and sometimes still are, regrettably) automatically considered to be the most likely suspects in any criminal investigation.  We now know this kind of discrimination is wrong.

But if fMRI machines, or their cheaper successors, ever attain the accuracy that Dr. Gabrieli hopes for, we will face a choice just as momentous as that faced by the nation when Dr. Martin Luther King challenged the nation with his dream in 1963.  Will we decide to sort people into rigid categories based on physical characteristics?  Or will we treat each human being as fully human, each fully deserving the right and opportunity to change and make better decisions regardless of what an imperfect scientific study says?  Those are the kinds of questions that we need to face before we inadvertently create a nightmarish regime in which your rights depend on the physical characteristics of your brain, just as much as they depended on the color of your skin in 1950.

Sources:  John Gabrieli's article "A Look Within" appeared on pp. 54-59 of the March 2019 edition of Scientific American.

No comments:

Post a Comment