Brain Stimulation Is a New Frontier for Treating Psychiatric Disorders

Dr. Flavio Frohlich is a scientist on a mission. The University of North Carolina at Chapel Hill researcher is working to establish a new field he calls network neuroscience – the use of gentle, non-invasive electrical brain stimulation to help treat psychiatric illnesses such as mood disorders and even schizophrenia.

The goal of the research is to shape, reshape and normalize brain activity patterns called alpha oscillations when they are abnormal. Alpha oscillations are rhythmic activity patterns that arise when the brain is in a state that is relatively disconnected from the environment, such as when you have your eyes closed. “We know that in depression and other mood disorders, there is a selective impairment of that type of activity pattern,” said Frohlich.

By applying transcranial alternating current stimulation (tACS), which sends a very weak (10 Hz) electric signal to the scalp via electrodes, Frohlich is able to join the conversation going on in the brain.“ We’re not overriding brain activity, we’re trying to collaborate and interact,” he observed. “The brain speaks electricity, we speak electricity, and together we can augment what is already naturally there.”

Frohlich and his team have already completed an intriguing study that showed that tACS can actually enhance a person’s creativity. In a carefully conducted, randomized, double-blind, placebo-controlled investigation involving 20 healthy volunteers, stimulation at the 10 Hz frequency boosted the participants’ creativity (as measured by a validated test) an average of 7.4 percent, with some individuals exhibiting dramatic creativity score increases. Stimulation in another group at a higher frequency, 40 Hz, had no such effect, showing that the improvements were specific to the alpha oscillation frequency, and not simply a generalized result of brain stimulation itself.

Mood disorder studies

The same stimulation method is being used in two clinical trials currently being conducted by Frohlich and colleagues, including UNC Psychiatry Department chair Dr. David Rubinow, exploring whether tACS may be useful in treating major depressive disorder (MDD) and premenstrual dysphoric disorder (PMDD), a severe form of PMS that affects 6-8 percent of women of child-bearing age. He says there is strong evidence that people with depression and other mood disorders have impaired alpha oscillations.

“In terms of how brain activity is organized, MDD and PMDD look very similar, with the same type of alpha oscillation impairment,” Frohlich noted. “So the vision is to take this shortcut and go after network activity patterns, and ignore some of the underlying cellular complexity.”

The theory is that by normalizing alpha oscillation patterns, a patient can much more flexibly engage and disengage from internal thought processes. “We want to help these patients by giving their brains this extra flexibility – that’s what we are trying to achieve with alpha stimulation in these mood disorders,” he said.

Quelling the voices

Frohlich’s group is also enrolling patients in a study to test the potential of tACS to treat auditory hallucinations associated with schizophrenia. The idea is that the part of the brain that processes sounds mistakes internal activity for actually hearing external sounds, and that brain stimulation may be effective in correcting that signal misinterpretation. He hopes to have results of the federally funded study in about two years.

Frohlich speculates that at some point, brain stimulation and psychotropic medicines will complement each other to optimize treatment of some mental illnesses.

Not so fast

Frohlich cautioned that although he has a high degree of confidence that his research is on the right track, it’s still early days, and there is much more work to be done in the laboratory before the technology is ready to be deployed in clinical settings. “We don’t yet have the evidence, that’s why we do the studies,” he said.

“Just because we’re testing this in clinical populations doesn’t mean it works,” he added. “Just because it’s overall very safe doesn’t mean that it doesn’t have detrimental side effects.”

But – “every single study is going to take us one step closer to these new, very safe and effective treatments for these devastating disorders.”