The 1980 DSM-III Revolution made it to my life around 1984 with the coming of a new chairman to my department. All he talked about was research. It took me a while to figure out that meant drug research. But from the start, he also talked a lot about PET [Positron Emission Tomography], a technique that located injected labeled compounds in the brain when compared to a simultaneous CT scan. I’d never heard of such a thing at the time. But the ability to do these scans promised to bring breakthroughs in our understanding of the brain and mental diseases. Over the years, almost every presentation I attended reiterated the great hope of these scans. In the 1990s, we heard more about the Functional Magnetic Resonance Imaging [fMRI] that uses Blood-oxygen-level dependent [BOLD] contrast. No injection of radioisotopes required. The process uses the change in magnetization between oxygen-rich and oxygen-poor blood to highlight changes in oxygenation and blood flow – an index of neural activity. We’ve all seen the dramatic pictures – they’re everywhere.
The problem has been that thirty years have passed, and while neuroimaging is still in almost every forward thinking presentation, it hasn’t added much of anything to our understanding of cognition or mental disorders. That has been a huge disappointment to biologiical psychiatrists and neuroscientists. Usually, a technological advance like that opens whole new worlds in research, like for example the coming of the X-Ray machines. Like another scientific advance, the ability to read the genome, the practical advances just haven’t materialized. I’ve mentioned that the DSM-5 Task Force went out on a limb in planning to add biological markers to their Manual based on anticipated discoveries. They were forced to abandon that plan when these two new technologies failed to produce anything of note. The assumption has been that this failure is because the techniques are just not refined enough, or that the samples are too small. Maybe our clinical diagnostic categories are too crude, or too broad. So now there’s the The Research Domain Criteria project [RDoC] at the NIMH – looking for new ways of classifying psychopathology based on dimensions of observable behavior and neurobiological measures.
My own take on things is easily predicted. I think that there’s a widespread categorical error in psychiatric thinking that way over-estimates the contributions of biology and brain to mental illness. So I would say that they’re looking for biology in too many places. But I’m an amateur. Dr. William Uttal is something of an expert, and he can’t seem to write enough books putting forth his hypothesis that the neuroimaging efforts are based on an assumption that may well be flawed. Jamzo passed on a review of one of Uttal’s books:
by William R. Uttal
MIT Press, 2012
Review by Maura Pilotti, Ph.D.
Oct 15th 2013
While this particular book discusses the methodological problems in the neuroimaging studies and their applications to the cognitive sciences, it also gets at one of Dr. Uttal’s major criticisms of the basic assumptions in these studies. This quote is from the end of another of his books [p 378] – Mind and Brain: A Critical Appraisal of Cognitive Neuroscience
This is a criticism that explains the poverty of yield from the neuroimaging studies in a much more fundamental way. He is proposing that the cognitive processes of the Mind may not map onto the anatomy of the brain in either the brain structures or the neural circuits – that they don’t correlate with places in the brain at all:
So what are we to make of all the studies that report something like an enlarged amygdala? thinning or thickening of various anatomical structures? lighting up of various parts of the brain with differing stimuli? Are they just wishes of the investigators? I obviously don’t know the answers to those questions. But I’ll have to say that I’ve personally never read a neuroimaging study that I left feeling, "Boy, they really nailed that one!" It’s always fuzz to me. Dr. Uttal raises the possibility that that’s exactly what those findings really are – just some fuzz…