Behavioural Geneticist Robert Plomin recently spoke with author Sam Harris on the Making Sense Podcast (Episode 211 – The Nature of Human Nature). They discussed a variety of topics related to the field of behavioural genetics with reference to Plomin’s book, Blueprint: How DNA Makes Us Who We Are.
Given my criticisms of behavioural genetics and its use in attempting to demonstrate the existence of discrete psychiatric ‘disorders’, it was a pleasant surprise to hear Plomin state the following during his conversation with Harris:
I really believe in psychiatry and psychology these diagnoses have held us back, tremendously. And all of the DNA studies—these genome-wide association studies—are case control studies. So, the whole game is to find these people who meet these—what I think are arbitrary diagnostic criteria—and you call them cases, like schizophrenics. And everybody else is a control. And that’s really held us back because it’s just simply not true. . . . I’m basically saying, there are no disorders, there are just quantitative dimensions. And one implication of that, then, is if there’s no disorder, there’s nothing to cure. It’s not like you’re cured, yes or no. It’s all quantitative. It’s a matter of more or less. We’re alleviating symptoms rather than curing a disorder.
Although continuing to refer to ‘schizophrenia’ as if it were a discrete disease entity throughout their discussion, it is nonetheless encouraging to hear leading scientists such as Plomin acknowledge that psychiatric diagnoses are fundamentally arbitrary (despite the existence of diagnostic manuals such as the DSM), and that the idea of a ‘cure’ does not make sense with regards to psychological issues.
Read the extended version of this blog post here.
