April 12, 2008

Brainwave Entrainment And Depression

Depression is one of the main reasons I became interested in developing brainwave entrainment software. The first system I designed had a depression session I used to wean off of high doses of antidepressants. So, when new depression research surfaces, as it did late last year, I just can’t wait to get my hands on it.

First, some thoughts on depression and BWE.

Many BWE sessions for depression owe their success to the studies on Neurofeedback, which has identified some key neural characteristics of chronically depressed people. The depressed brain seems to exhibit lower overall brainwave amplitudes, and seems particularly deficient in the beta range. Alpha also seems overly abundant frontally, in the left hemisphere, and deficient in the right. You could say that the right hemisphere, which tends to be loosely associated with emotions, needs to be calmed down, while the left hemisphere, loosely associated with logic and rational thinking, needs to be stimulated into taking a more dominant role.

For people who are or have been chronically depressed, this may sound more than a little bit familiar. Rational thoughts play no part in depression. When asked why you are depressed, there really is no good excuse.

Based on the results of these EEG tests, brainwave entrainment sessions for depression were developed to stimulate beta. In some cases, alpha is sent to the right hemisphere to calm it down, while beta is sent to the left to perk it up. This is the type of session I used for myself.

In a study on Seasonal Affective Disorder (essentially, seasonal depression), Kathy Berg and David Siever used beta stimulation to raise 85% of the subjects out of depression. Anxiety and over-eating decreased. Motivation even increased. Siever has told me that more studies on depression are in the pipeline, waiting to be published.

I’ve also seen Gamma sessions used successfully for this purpose. The energizing effect alone is very beneficial to depressed individuals, who often feel as though they are “sleep walking” through life.

The latest study, which I’m going to discuss in a moment, also used beta, and reported some really extraordinary results as well.

However, depression is a broad topic. It obviously isn’t limited to people with low beta waves or frontal alpha asymmetries. Everyone gets depressed. Every few weeks I get an email from a user who used the depression session after having a bad day, or a bad week, and unfortunately most of the time a beta session just doesn’t work for them. This is not unexpected, since depression sessions are designed for the chronically depressed, not to help lighten the mood on a dreary day.

For melancholy caused by the everyday trials of human life, a pleasant relaxation session tends to work better. And there is some research to support this as well. Dr. Norman Shealy examined the effect of 30 minutes of 10 Hz stimulation, and found that it was enough to lift 60% of his subjects out of depression. He also noted an increase in serotonin levels.

High stress levels, anxiety and insomnia can also be the cause of depression. For these causes, even theta can be very helpful. But be cautious when dealing with slower frequencies, particularly theta and delta. Two separate studies (Lane, 1998, Wahbeh, 2007) found that theta and/or delta could actually increase depression scores (using the POMS, Profile of Mood States, test). Interestingly, the Lane study also showed that beta decreased those same depression scores.

Now to the new research.

Late last year,David Cantor, Ph.D. released some of the details of a new brainwave entrainment study on depression at the annual conference of the EEG and Clinical Neuroscience Society.

He used 14 Hz stimulation daily for 4 weeks, using pulsing tones and LED glasses.

Here are the results:

After 4 weeks, [Beck Depression Inventory] testing revealed “a huge drop” in self-reported depression scores in the treatment group, compared with no change in the untreated group, said Dr. Cantor.

QEEG testing also showed neurophysiologic changes in the treated patients (but not the untreated group) that corresponded to their reports of improved mood. “The QEEG changes we saw were noted in the frontal regions of the brain that have been shown by other studies to be involved in mood regulation,” he said.

The groups were then crossed over, so that the untreated group received treatment and vice versa for another 4 weeks. Similar results were noted in the newly treated group, but the group that had received the first phase of treatment showed a sustained effect of treatment, both behaviorally and neurophysiologically, even after 4 weeks of discontinuation. “That is suggestive of an enduring effect of the therapy,” Dr. Cantor said.

“To our knowledge, this may be one of the first studies that shows, in a crossover design, that audiovisual entrainment produces changes in brain function in particular regions that are involved in mood regulation,”

I find it particularly exciting that the effect lasted even after stimulation was discontinued. I can relate this to my own experience. I haven’t had to use the depression session hardly at all after the initial couple months of daily training.

There has been some debate over the years about whether the results of entrainment can become permanent. Some neurofeedback books I’ve read have adamantly claimed that it can’t, yet a growing body of evidence and follow-ups are starting to prove otherwise. Brainwave entrainment seems to increase the “flexibility” of the brain, or the ability to switch between one state and the next. For ADD and general cognition, research has shown the effects to be very long-lasting, and now perhaps we will start seeing similar results for other problems such as depression.

Here is an article on Cantor’s work if you’re interested: http://www.entrepreneur.com/tradejournals/article/172316583.html

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