Can Technology Help Treat Depression?
Sonya Collins | WebMD Health News | Wednesday, April 29, 2015
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What are we learning about our brain and mental health? Amit Etkin, MD, PhD, assistant professor of psychiatry and behavioral sciences at Stanford University, spoke on that topic as part of an expert panel at the Association of Health Care Journalists annual conference last week. WebMD spoke to Etkin about how technology is helping us learn more about the causes and treatment of depression and other mental illness.
Q: What can brain imaging tell us about depression, anxiety, and PTSD?
A: Imaging can tell us how similar a person with any one diagnosis is to another and how similar or different people are who have the same diagnosis. It can also help us predict who will respond to what kind of treatment.
There are cases where you see similarities in brains across two similar disorders, or you can see differences between similar disorders. But the really surprising thing is actually the similarities across disorders that aren’t symptomatically that similar. The checklist of symptoms that we use to make diagnoses suggests that diagnoses like drug abuse or schizophrenia or depression are actually separate disorders, but imaging shows that they still share some common biology. That speaks to the limited nature of our diagnostic checklists to begin with and how much the brain can tell us.
Mental illnesses have always been defined by their symptoms. But symptoms are just external cues that something is going on. If a person doesn’t report symptoms or no longer has the behavior, it doesn’t seem logical to conclude that there’s not something still going on in their brain. For example, with drug addiction, you can stop using drugs, but there’s a major risk of relapse, and that has to do with something continuing in the brain even after you stop using. Ultimately imaging is our only measure of the brain itself. Psychiatry has to be grounded in the biology of the brain as the organ that underlies mental illnesses. As such, having a tool that tells us something about the brain, however precise, is already an important step forward.
Q: What is transcranial magnetic stimulation (TMS), and how might it help people with depression?
A: TMS is a non-invasive way of stimulating the brain. It uses a powerful electromagnet that you place outside of the head, targeted at one specific part of the brain. It turns on a magnetic field that’s as strong as a regular MRI but lasts less than half of a millisecond. This magnetic field turns on or off neurons in the brain, such as those that contribute to depression. If you then do this repeatedly over time, you end up retraining the particular circuits that you’re targeting to function correctly on their own.
The FDA approved it to treat depression, and it’s being studied in a range of other conditions. It’s the first treatment approach that takes particular circuits in the brain as a primary target and affects them directly to treat depression.
Q: Can we expect to see TMS emerging to address other psychiatric issues?
A: People are using TMS in any number of conditions, whether it’s chronic pain, schizophrenia, OCD (obsessive-compulsive disorder), PTSD, or others. For the most part, those TMS interventions are essentially very similar to the one for depression. Research is exploring which circuits in the brain we should target with TMS. Ultimately, we cannot target the same one area that we have targeted with TMS for depression over the last 20 years, but have to find the ones that are right for the individual person and their illness.