Cells, Circuits, and Syndromes: A Critical Commentary on the NIMH Research Domain Criteria Project
McLaren, Niall, Ethical Human Psychology and Psychiatry
The US National Institute of Mental Health (NIMH) has recently declared a new research program for psychiatry, the Research Domain Criteria (RD°C), as the successor of the long-standing Diagnostic and Statistical Manual of Mental Disorders (DSM) diagnostic program. However, the new program is based on a series of assumptions that, on analysis, lack any formal scientific standing. Essentially, as presently conceptualized, the RD°C program is no more than ideology masquerading as science, and thus cannot achieve its stated goals. It is argued that the program will lead psychiatry into intellectually sterile areas because it is in fact the wrong research program for the present state of our knowledge.
Keywords: NIMH; RD°C; philosophy of psychiatry; pseudoscience
In several strategically placed editorials, the directors of the National Institute of Mental Health (NIMH) have recently outlined their "vision for the future" of psychiatry (Cuthbert & Insel, 2010; Insel et al., 2010; Yan, 2010). The plan commits psychiatry to a new research program lasting-one assumes-well beyond the lifetimes of many of today's practitioners. These articles are of much greater significance than a brief reading implies so, in this commentary, I can do no more than indicate their general position.
OUTLINE OF NIMH PROGRAM
The first step in the major article (Insel et al., 2010), a commentary in American Journal of Psychiatry, is an acknowledgment that the current DSM program, initiated in the mid- 1970s, has not achieved what its founders hoped:
Diagnostic categories based on clinical consensus fail to align with findings emerging from clinical neuroscience and genetics. The boundaries of these categories have not been predictive of treatment response . . . (they) . . . may not capture fundamental underlying mechanisms of dysfunction. One consequence has been to slow the development of new treatments targeted to underlying pathophysiological mechanisms.
Accordingly, they believe that
. . . the question now becomes one of when and how to build a long-term framework for research that can yield classification based on discoveries in genomics and neuroscience . . . the time has arrived to begin moving (toward a) . . . Research Domain Criteria (RD°C) project to create a framework for research on pathophysiology, especially for genomics and neuroscience, which ultimately will inform future classification schemes.
The underlying assumptions are then rendered explicit:
First, the RD°C framework conceptualizes mental illnesses as brain disorders . . . mental disorders can be addressed as disorders of brain circuits. Second, RD°C classification assumes that the dysfunction in neural circuits can be identified with the tools of clinical neuroscience, including electrophysiology, functional neuroimaging, and new methods for quantifying connections in vivo. Third, the RD°C framework assumes that data from genetics and clinical neuroscience will yield biosignatures that will augment clinical symptoms and signs for clinical management.
They warn, however, that
. . . given the rudimentary nature of data relating measures of brain function to clinically relevant individual differences in genomics, pathophysiology, and behavior . . . In the near term, RD°C may be most useful for researchers mapping brain-behavior relationships as well as genomic discoveries in human and nonhuman animal studies . . . RD°Cs are intended to ultimately provide a framework for classification based on empirical data from genetics and neuroscience.
Nonetheless, "Our expectation, based on experience in cancer, heart disease, and infectious diseases, is that identifying syndromes based on pathophysiology will eventually be able to improve outcomes."
At this point, the authors indicate the nature of their research program:
The primary focus for RD°C is on neural circuitry, with levels of analysis progressing in one of two directions: upward from measures of circuitry function to clinically relevant variation or downward to the genetic and molecular/cellular factors that ultimately influence such function. …