Tuesday, November 22, 2011

Who needs DNA when we've got fMRI?

Neuroscience is the new genetics, the explanation for everything that ails you, and for why you are who you are.  Where your brain 'lights up', as caught on fMRI scans, when you're doing some task -- lying, serial killing -- apparently tells the researcher a lot about you. "It wasn't my fault, my brain made me do it," may be a defense soon coming to a criminal court near you.

fMRI, amygdala in red
The story of the perfectly normal man who slowly and stealthily became a pedophile, finally caught by his wife when he began to molest his 11 year old stepdaughter, is only one of many that are causing people to rethink the idea of responsibility for our behavior, and indeed, free will.  This man came to the attention of a sympathetic physician, who decided he needed an MRI, which showed that he had a large tumor on his frontal lobes.  When the tumor was removed, the man's pedophilia disappeared entirely.  When he began to be interested in children again, it was found that the tumor had recurred.  The tumor was again removed; the legal charges were ultimately dropped against this man, deemed to not be responsible for his behavior.

This story was repeated on a BBC Radio 4 program about understanding the criminal brain, and it gave us occasion to muse once again about causation.  Neuroscientists are doing a lot of work on what is malfunctioning in the brains of sociopaths.  And how can you doubt their word?  You can see it on scans.

Serial killers have less activity in their amygdyla, which leads to less empathy, which leads to antisocial behavior.  And, according to the show, this aberrant brain activity can be identified in severely misbehaving children, kids, they claim, who are likely to grow up to be criminals.  (Will this lead to preventive measures taken by the state to lock up or dope up those whose 'brain will make you do it'?)

A school in England is now addressing this problem head-on (so to speak).  Armed with fMRI scans of kids with serious behavior problems, the malfunctioning part of the brain identified, the school has developed a method to work with these kids to activate the caring parts of their brains.  So, for example, they show them pictures of fearful kids and teach them how to tell how the kid is feeling, both from the face and from body language, clues that the students aren't good at picking up.  The hope is that these brains are rewireable, so that the kids will grow up to be contributing members of society.

But there's a kink in this analysis.  It is both reductive, and of course reminiscent of claims of behavioral geneticists -- my brain structure, or my genes, made me do it -- and expansive at once.  If the criminal (or future criminal) brain is plastic enough to respond to environmental pressures in the form of teaching, and it can in fact remold itself, then that suggests that something malformed it in the first place.  And here we're back to the age-old questions of social causation, and then of course ultimate responsibility -- does poor parenting make criminals?  Poverty?  Bad luck?  So, the reductive explanation is not a complete one after all.

The problem is simple, even if the solution, if there is one, isn't.  After the 'bad' behavior has occurred, one seeks any tecchie gear that will show why, in a reductionistic way (bad gene, tumor, --- some built-in molecular 'cause').  And even if it's clear that non-technical experiential factors can fix the problem, it is not so easily recognized that such factors may have caused the problem.  The random population is not screened to see how many non-sociopaths have the same brain activity patterns, for example.

More importantly, if it is assumed that the technical finding (genotype, fMRI signature) is causal, a likely consequence, if history is any guide, will be to use the same findings 'preventively'.  That was the basis of the eugenics movement, and anybody who thinks something of its ilk can't happen again hasn't read any history.   Eugenics -- the very term itself! -- was the purportedly benign attempt to improve society through science.

Even if that risk is not taken seriously, we still have serious problems in dealing with this kind of causation and association data, or of putting non-technical facts in the same perspective as we put technical ones: we're too enamored of the latter, in this Age of Science.


Holly Dunsworth said...

Thanks Anne.

Pat Shipman said...

Is this "my brain made me do it" different in any serious way from "the devil made me do it?" Only now we use a scalpel to exorcise the tumor? If absolutely everyone with this frontal tumor is a pedophile, then I'll buy this 100%. If only some are, then it is like growing up _____ (fill in the blank: poor, the wrong color, in a broken family, handicapped, dyslexic...) as an excuse for criminal behavior. I persist in believing we have some responsibility for how we handle the issues we have been given genetically.

Ken Weiss said...

Geez, you probably don't believe your genes made you do it, either! You must be one of those who is stubbornly against science and deny that scientists are the smart people who know the truth, the whole truth, and nothing but.

John R. Vokey said...

As much as I must agree with Ken (above: and how could I disagree?), there really is NO point in discussing these issues until all and sundry have read Dan Dennett: Freedom Evolves http://www.amazon.ca/Freedom-Evolves-Daniel-Dennett/dp/0142003840/ref=sr_1_5?s=books&ie=UTF8&qid=1322293057&sr=1-5
, and its causal (hah!) precursor: Elbow Room: The varieties of free will worth wanting

Otherwise we spend all our time running around in centuries' old circles of no import. Instead of those tired, old dispositions, let Dennett define the default, and begin the argument there. I suspect most will find that they have none, other than: na-hah, or, is so.

Anne Buchanan said...

As long as it's clear that behavior is complex, and as unpredictable as, say, heart disease, where the parameters of risk may be generally understood but a given heart attack may occur seemingly out of nowhere, and the heart attack that everyone knows is going to happen never does, reductionist approaches to behavior, to understanding causation and thus prediction are not going to be helpful. As with heart disease, when we'll never know on an individual basis why a given heart attack happened, and how many we prevented, we'll never know who is destined to become a serial killer and how many murders intervention has prevented.

What do we know about behavior? That brains are plastic, and behavior is due to the interaction of genes, environment, experience, and chance. That says it all, but it says nothing. And I don't know how we can know any more than that.

Ken Weiss said...

I have not read the Dennett things you cite, and am not a big fan of his anyway, because I think he's far too much of a Darwinian determinist (and I don't care for the strident atheism, which I think is gratuitous). As long as there are so many neurons and interconnections, and so much stochasticity in development and brain function, and so little understanding of what that stochasticity really means, one can take a philosophical view that free will is an illusion of what's at heart a purely deterministic process. Or one can say that probability plays such a role that there really is not the kind of predictability that a mechanical determinist would argue makes 'free' will an illusion.

The key to truly free will would be if it is totally un-forced--that is, not due to any force. That would put it beyond the realm of any science that we know of today.

Since I certainly don't know enough to judge how free is free, and see no evidence beyond wishful thinking that there is truly free will, I can't really see the point of arguing about it.

But if I have time I'll try to see what Dennett says about it.