9 May, 13 | by Iain Brassington
Thanks to Brian Earp for bringing this release from the US’ National Institute of Mental Health to my attention; it concerns the Institute’s decision to move away from DSM as its diagnostic tool. DSM has been enormously successful – in terms of having established itself at the centre of psychiatry – but it has been enormously controversial, as well; the NIMH moving away from it is very big news indeed. Whether the new model that they’re going to be working on will be any better, of course, remains to be seen.
The important bit seems to be this:
NIMH will be re-orienting its research away from DSM categories. Going forward, we will be supporting research projects that look across current categories – or sub-divide current categories – to begin to develop a better system.
One or two things about the statement leap out at me.
Through a series of workshops over the past 18 months, we have tried to define several major categories for a new nosology (see below). This approach began with several assumptions:
- A diagnostic approach based on the biology as well as the symptoms must not be constrained by the current DSM categories,
- Mental disorders are biological disorders involving brain circuits that implicate specific domains of cognition, emotion, or behavior,
- Each level of analysis needs to be understood across a dimension of function,
- Mapping the cognitive, circuit, and genetic aspects of mental disorders will yield new and better targets for treatment.
In one sense, these are all perfectly true. But the second point is intriguing; I’d be interested to know if there were any metaphysicians sitting alongside the physicians in these workshops. After all, any philosophy undergrad can admit that mental function (and illness) involves brain circuits; the puzzle is getting that to provide a sufficiently rich account of what it’s like to have a mind – and. implicitly, what it’s like to have a problem with your mind. In short, there could easily be more to the mind and what it does than brain circuitry – and admitting this doesn’t commit you to Cartesianism. Getting the question right, though, would seem to be important. It’s a prerequisite for providing a decent answer.
[I]t is critical to realize that we cannot succeed if we use DSM categories as the “gold standard.” The diagnostic system has to be based on the emerging research data, not on the current symptom-based categories. Imagine deciding that EKGs were not useful because many patients with chest pain did not have EKG changes. That is what we have been doing for decades when we reject a biomarker because it does not detect a DSM category. We need to begin collecting the genetic, imaging, physiologic, and cognitive data to see how all the data – not just the symptoms – cluster and how these clusters relate to treatment response.
That final sentence shows why the mind/ brain question is important. How big a part are symptoms going to play in diagnosis? The phrase “not just” implies that symptoms are going to be a necessary component in any diagnosis and treatment; but it isn’t absolutely certain: the way seems to be open to a possible world in which genetic, imaging, physiologic and cognitive data could in some cases “swamp” the symptoms. Equally, suppose that a person reports some kind of mental dysfunction, but the other data are absent? What then?
Heres the thing: the analogy with chest pains doesn’t work. When it comes to physical function, we can imagine someone being wrong about whether or not there’s a medical problem: we can imagine a world in which a person somehow has a heart attack without noticing, and whose behaviour is not altered, but in which we can point to the damaged bit of heart and say, “No, look: there is some clear damage. It’s a real aspect of the real world”. If the analogy is sound, that’d suggest that we could do the same with the mind: look at the genetic and imaging and all the rest of it data, and insist that there is something wrong after all. And I’m not sure that that’s correct. To what would we point that isn’t either a matter of what one feels, or of how one behaves?
My understanding of a lot of the worries about DSM is that it suffers from a kind of diagnostic creep – perhaps verging itself into PATHOLOGISE ALL THE THINGS! territory. Adverting to brain science won’t solve that problem; and thinking that brain science is the solution might make it worse.
This is not to say that brain science contributes nothing; but – and this isn’t my area of expertise at all – the thing about mind-medicine is that it requires a willingness to interpret, and so to infer non-scientific values, right from the start.
UPDATE: I make no bones about this not being my area of expertise. I’m casting about a bit, and unashamedly so…