Biomarkers – ‘Precision Medicine’ for the Brain

From the time of the ancient Greeks, medical practitioners have searched for biomarkers for physical illnesses. Hippocrates tasted patients’ urine for sweetness (he is thought to have been the first to diagnose diabetes mellitus).  More recently, doctors relied on patients’ complaints about the severity of their chest pains in order to diagnose a heart attack. Today, they measure cardiac enzymes in the bloodstream.

Think of it this way: Cancer treatment doesn’t treat the symptoms of cancer.  You don’t want the swelling to go down or the pain to disappear; you want to get rid of the cancer.  But that’s the protocol clinicians and researchers have used for years – the cataloging of symptoms such as sadness, fatigue and loss of appetite, rather than looking for biological clues associated with the symptoms in a blood test, a brain image or a saliva sample. The focus was treating the symptoms of mental disorders, not the causes.

Neuroscience’s inroads have emboldened a small but growing number of clinicians and researchers to reject diagnostic protocols on which mental health practitioners have relied for years and instead focus on finding the biomarkers, the concrete measurements of mental illness.

There was a huge shift in the approach to diagnose and treat mental illnesses beginning in 2013, when the National Institute of Mental Health announced that the government, the largest funder of mental health research in the world, drastically shifted its priorities.  Research based solely on the Diagnostic and Statistical Manual of Mental Disorders, the chief tool of mental health professionals, would no longer be funded.  The reason was “its lack of validity.”   First published in 1952, the manual has changed over the years, but its categorization of mental illnesses was based nearly entirely on symptoms either reported by the patient or observed by the clinician.  New funding is based on the premise that mental disorders are biological disorders involving brain circuits. Research into diagnosis and treatments such as talk therapy became relegated to the bottom rung of the research ladder.

New psychiatric methods visualize the nervous system and its activities, monitoring the physiological dynamics of mental health.  Rather than targeting brain chemistry to reduce symptoms, researchers now want to focus on brain circuitry.  Their efforts have been bolstered by advances in technology and imaging that now allow scientists not only to see deeper into the brain, but also to study single brain cells to determine which circuits and neurons underlie specific mental and emotional states.

Because of this huge shift from ‘brain chemistry’ to ‘brain circuitry’ some traditional psychotherapists are evolving onto “neurotherapists,” someone who first tries to understand a patient’s brain circuitry, then combines that with both psychological and physiological information to create a treatment plan.

While traditional psychotherapists might begin sessions by asking patients about their thoughts, feelings and problems, new diagnostic protocols might have patients fill out a color-coded form that matches statements about their thoughts and feelings with the parts of the brain most likely involved. Then patients undergo a quantitative electroencephalograph, or qEEG.

The EEG is a map of the brain’s electrical activity and reflects a patient’s emotional and cognitive states. The qEEG compares that information, in real time, to a digital database of hundreds of EEGs of healthy subjects. A patient’s brain map will pulse with red or blue if it is either overactive or under-active, compared with the norm.

Patient treatment plans can include psychotherapy and medication as well as neurofeedback, a technique in which patients are trained to increase or decrease brain-wave activity in the parts of the brain related to their complaints. Another tool is transcranial magnetic stimulation, a noninvasive method of delivering pulses of energy to the head, which has been approved by the Food and Drug Administration for the treatment of depression.

A person’s mental makeup is a kind of hierarchy, with personality on top, which is created by brain states that arise from circuits firing in a certain pattern below. With psychotherapy, you tweak the brain from the top down, dealing first with a patient’s personality and temperament. But with neurofeedback, combined with qEEG, patients are tweaked his from the bottom up, identifying the brain areas involved and then retraining those circuits to fire differently, resulting in changed moods or mental outlooks.

It’s a more precise way to  and it sure beats trial and error.

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