The brains of people with major depression, when monitored with electro-imaging technology, appear to function differently from those who don't have the disorder, researchers say.
A recent study conducted at the University of California, Los Angeles monitored brain function using electroencephalography, a technique that measures electrical activity of the brain.
The study of 158 participants, aged 21-70, was published Feb. 24 by the Public Library of Science, in the journal Plos One.
Of all the participants, 121 had a diagnosis of major depressive disorder, which is characterized by restless and anxious mood, difficulties in concentration and a lack of motivation. The remaining 37 participants were considered to be healthy, which meant they were free of depressive symptoms.
"We know that depression is not simply a feeling state, it is actually marked by changes in brain function," said Andrew Leuchter, a professor of psychiatry and biobehavioral sciences at UCLA. Leuchter was lead author of the study.
The study found greatly increased connectivity, or hyper connectivity, in specific brain regions in the depressed patients. Leuchter said this indicates the brain is losing its ability to selectively transmit information. A normal brain can actively turn connections on and off, but the observed depressed brain seemed to have lost that ability.
In addition, the tightly linked connections of the depressed brain make it less flexible, creating difficulty in the person's ability to react appropriately to certain events. Those with depression can tend to make catastrophes of situations that healthy individuals can deal with in a calm and rational manner.
Ian Cook, an author of the study and professor of psychiatry and biobehavioral sciences at the David Geffen School of Medicine at UCLA said, "Our hope is that this line of work will open up a new perspective on what is going wrong in the brain when a person is depressed. We really do need to look at the network within the brain, not just the specific areas in isolation."
Depression costs the U.S. economy an estimated $51 billion in missed work or lost productivity, and an additional $26 million in treatment costs each year, according to Mental Health America.
New types of brain stimulations, which can alter brain functions in targeted areas are being researched and used as treatment for depression. Transcranial magnetic stimulation, or TMS, in which a magnetic field is used to stimulate one specific part of the brain, is one non-invasive alternative treatment. The therapy was approved by the Food and Drug Administration in 2008, and is now offered in hundreds of clinics around the country.
Cook runs the TMS program at UCLA and currently researches other methods of brain stimulation treatment as well.
Neil Bockian, professor of clinical psychology at the Adler School of Professional Psychology in Chicago is a specialist in brain-wave therapy treatments for depression. Bockian has long used quantitative EEG, the same technique used in the study to measure the electrical impulses in the brain, in treating depression. He also utilizes neurofeedback, in which the patient learns to balance the level of brain wave activity between the two sides of the brain.
"Having another avenue to treat it is very encouraging," Bockian said. These types of treatments hold promise in helping those with depression. "This is a step forward in something that is affecting tens of millions of people," he said.