The Clinical Use of Sound

Dr. Jeffrey D. Thompson, D.C., B.F.A.

 Human beings have been using sound to access deeper states of consciousness, expanded awareness and heal the body for thousands of years. Chanting, toning, Tibetan singing bowls, Chinese meditation gongs and the use of mantras are just a few examples. 

Today, with highly sophisticated technological equipment, we can observe the functioning of the body and the brain in unprecedented detail. 

Research projects in major universities across the country have explored the neurophysiology of meditation, deep relaxation states and mind/body interactions during healing. In one study a simple meditation technique used for 20 minutes a day caused profound changes in blood pressure, stress handling ability, immune response and feelings of well being - never mind using any kind of high-tech approach which could bring consciousness to very deep levels of relaxation. Using this technology as a daily tool for mind/body integration and stress reduction can have many positive benefits. 

Brainwave Entrainment

The definitive work on the discovery of the phenomenon of acoustic brainwave entrainment - the ability to change brainwaves and states of consciousness with sound - was done by a medical researcher at Mount Sinai Hospital and published in the Oct 1973 issue of Scientific American entitled "Auditory Beats in the Brain". In this article, he outlined the research he had conducted which showed a brainwave entrainment response to something he called "Binaural Beats". These beats occurred when two separate tones were tuned slightly differently from one another - to be precise: within 18% of one another - a range called the "Critical Bandwidth". The speed of the beats is governed by the difference in the frequency of the two notes: a left channel tone of 100 cycles per second (Hz) and a right channel tone of 105 Hz would cause a 5 Hz pulse to arise as an interference pattern. The brain would entrain and slow its function to this 5 Hz speed and therefore an altered state of consciousness would result. He also found, that listening to these two frequencies through headphones caused not only the brainwave entrainment phenomenon, but a synchronicity of the electrical activity of the right/left hemispheres as well.

Hemisphere Synchronicity

This phenomenon of hemisphere synchronicity is due a quirk in how the brain processes information and the physics phenomenon of the Critical bandwidth. When two tones are tuned within 18% of one another (or within the critical bandwidth) the brain cannot distinguish two separate tones, it hear one single tone with a pulse within it. The speed of the pulse it hears is the difference between the two tones. Through headphones, however, the opposite hemispheres, which process sound information from each opposite ear, have to compare information in order to hear the pulse. Actually the brain is manufacturing the pulse out of thin air, moment by moment. When the hemispheres compare information, they synchronize their activity: thus hemisphere synchronicity. 

We know from other research efforts that brainwave synchronicity does not happen often and when it does it is only for an instant. We know it is associated with the "aha" moment, the moment when the answer to a problem pops into the mind, in times of great inspiration, and certain high states of revelry and meditation. With this new technological method of entraining brainwaves with binaural beats using headphones, however, it is possible to float the brain in this hemisphere synchronicity state for prolonged periods of time. Each time we do this, it is like exercising a new brain function - which makes the brain more able to engage this function as its normal repertoire of behavior. It is like going to a gym on the inside and working the "muscle" of your brain. 

Using sound in these ways, it is possible to make profound changes in brainwave patterns and states of consciousness, observable on brainwave mapping equipment (EEG), as well as positive changes in the body, measurable with blood tests, bio-feedback equipment and other sophisticated procedures. We are also able to influence the core balance and functioning of the brain and central nervous system as a whole. 

In a series of recordings based on these principles I have used sound frequency patterns built into the music that have been shown clinically to cause positive changes in consciousness, brainwave and body function.

This process involves the use of digital technology, electronic keyboards and computer programs which make it possible to take any recorded sound - instrument sounds, nature sounds, human voice sounds, etc. - and precisely alter the tuning of the right/left channels of these sounds (a precision of 100 steps of tuning between two notes on a piano) which causes an interference pattern of pulses to arise by the difference of tuning. If the speed of these pulses is calibrated to a brainwave speed (Beta, Alpha, Theta, Delta), then the brainwaves will follow the speed of these pulses and brainwave entrainment will occur. 

There are other methods for building pulse rates into soundtracks that cause brainwave entrainment, but are not based on the idea of binaural beats. We can modulate the amplitude, filters and pitch of the sounds as well. This means we can build a pulsing loudness level, a pulsing bass/treble level and a pulsing sharp/flat level in the sounds. All of these systems work to cause the entrainment response, but only the binaural beat through headphones technique causes the hemisphere synchronicity response in the brain. 

A good part of the stress we all experience in the twentieth century is due to the advancements of our own technology. This same technology, combined with our traditional techniques for healing and achieving balance, may help neutralize the stress we created.