05/16/2013 12:27 pm ET Updated Jul 16, 2013

NIMH: Neurology Trumps Psychiatry

There's a battle brewing over the future of mental illness. In one corner is the American Psychiatric Association (APA) defending their new release of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) as the best way to define who has a mental illness and who doesn't. In the other corner is Dr. Thomas Insel, director of the National Institute of Mental Health (NIMH), claiming it "lacks validity."

They are both right. Perhaps Dr. Insel more than the APA.

DSM catalogues symptoms and classifies certain constellations of symptoms as indicating the presence of a disorder. That works when only extreme symptoms are considered as indicative of mental illness. The extreme symptoms of schizophrenia and bipolar -- hallucinations, delusions, and cognitive impairments -- are enough to tell us something is wrong, even if we don't know what it is. But with each iteration of DSM, the APA has gathered less extreme symptoms together and decided they also indicate the presence of illness. The number of diagnoses exploded and normality -- like having too much grief when someone dies -- has now gained a label and a billing code.

Perhaps nowhere is this trend more hurtful than in children. Kids no longer grow out of anything anymore. The Onion captured it best: "More U.S. Children Being Diagnosed With Youthful Tendency Disorder."

This medicalization of normality may be good for business, but not our public policy or pocketbooks. Politicians have uncritically followed the APA lead and now fund a whole host of "mental illnesses" that may exist more in the minds of APA members than the patients they serve. Mental health is now a $100 billion industry that is largely publicly funded. Serious mental illnesses continue to lose funding to "all other."

Enter Dr. Thomas Insel. He argues for a neurological approach by pointing out:

Unlike our definitions of ischemic heart disease, lymphoma, or AIDS, the DSM diagnoses are based on a consensus about clusters of clinical symptoms, not any objective laboratory measure. In the rest of medicine, this would be equivalent to creating diagnostic systems based on the nature of chest pain or the quality of fever. Indeed, symptom-based diagnosis, once common in other areas of medicine, has been largely replaced in the past half century, as we have understood that symptoms alone rarely indicate the best choice of treatment.

His goal is to "transform diagnosis by incorporating genetics, imaging, cognitive science, and other levels of information" based on the premise that "mental disorders are biological disorders involving brain circuits ... and mapping the cognitive, circuit, and genetic aspects of mental disorders will yield new and better targets for treatment." Neurology, not psychiatry.

But we're a a long way from being able to do that. There's not enough money, and brain imaging technology and algorithms have progressed but are not yet well-enough developed. So where does that leave us? We still have to rely on DSM to diagnose illness, but thanks to Dr. Insel the end of that state of affairs is a step closer. The identification and treatment of mental illness is about to leave the realm of psychiatry and enter the science of neurology. That should benefit everyone.

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