What if you could decide exactly what mood you were going to be in and when? If you could fine tune your brainwaves so you could concentrate better at work or relax more on your day off? With brainwave synchronization, you can. But how does it work?
Neurons, or brain cells, send signals causing electrical activity to different parts of the brain. This electrical activity is what researchers have named brainwaves. Different waves are associated with different mental states and can be stimulated to change a person’s state of mind. Brainwave entrainment is the practice of changing one’s brainwave pattern to a specific frequency by stimulus with the corresponding frequency to adjust mood and concentration levels. This article will discuss and explore the history of brainwave entrainment and the different techniques.
In 1839 a man named Heinrich Wilhelm Dove noticed that if you play a different tone that blends naturally in each ear it creates a beat that is not actually there. Dove called these perceived beats “Binaural Beats”. When he discovered the beats, they were considered an oddity of the brain and nothing more. Research continued on the potential to use binaural beats as a diagnostic tool for finding auditory and general neurological problems but, because the brainwave wasn’t discovered yet, no one originally considered a side effect of these beats being mood and concentration enhancement.
Hans Berger discovered Alpha brainwaves in 1929 and researchers found the strength of brainwaves could be driven beyond normal frequency using flickering lights. This process is called “Photic Driving”. Less than twenty years later, in 1942, Dempsey and Morrison discovered that repetitive physical stimulation could also affect the brainwaves while in 1959 Dr. Chatrian noticed auditory entrainment in response to fifteen clicks per second administered to the subject.
In the 60s, brainwave synchronization became a tool rather than a strange phenomenon of the brain and in 1973 Dr. Gerald Oster wrote an article for Scientific American called “Auditory Beats in the Brain”. In his paper, Dr. Oster discussed the differences between binaural and monaural beats. He noticed that monaural beats got extremely strong cortical responses (electrical activity in the brain that is responsible for synchronization) though binaural beats produced very little neural response. In conclusion, Dr. Oster stated that binaural beats could be useful in diagnosing neurological disorders while monaural beats would be useful in entrainment of the brainwaves.
Brainwave synchronization, also known as brainwave entrainment, is a way to change one’s state of mind by adjusting the brainwave activity. Stimulus can be aural , visual, a combination of the two or electromagnetic radiation. They are a form of frequency-following response which is a naturally occurring phenomenon where the human brain has a tendency to change its dominant EEG frequency to match the dominant external stimuli applied to it. This can cause changes and, in most cases, improvement in mental state such as increased intelligence, creativity, relaxation, pure energy, temporary pain relief, temporary stress reduction, sleeping disorders and meditation.
So what are these beats? And how do they work?
Binaural beats are the perceived rhythm produced when a slightly different tone is played into each ear simultaneously. For example, if one were to emit a tone of 400 hertz into the subject’s right ear, and another tone of 410 hertz in the subject’s left ear at the same time, the brain produces a beating rhythm of 10 hertz. These beats are only heard if the tones mix naturally and the frequency must be below 1500 hertz. This rhythm causes a number of things to happen in the brain, not the least of which being a change in the frequency at which neurons function. This change in frequency, depending on the brainwave it corresponds with, can change anything in the person’s behavior and mood from how they sleep to how hard they concentrate on tasks given to them.
Binaural beats became of interest to neurophysiologists who were researching hearing and ways to diagnose hearing problems. Dr. Oster, in writing his article, discovered that binaural beats are an excellent tool for cognitive and neurological research. He studied how animals locate sounds and their ability to pick out and focus on specific sounds in the forest of noise. He also discovered that patients with Parkinson’s Disease couldn’t hear binaural beats at first but, with treatment, they eventually could hear them again. And finally, Dr. Oster discovered there was a difference in how men and women perceived the beats. Women have two peaks in perception which possibly coincide with different times in their cycle such as ovulation and menstruation.
Dr. Oster discovered that monaural beats have a higher neurological response than binaural beats do, which makes them better for brainwave synchronization. However, monaural beats, while considered better for entrainment than binaural beats, aren’t used that frequently. The two tones in monaural beats have to be at the exact same volume to work whereas the tones in binaural beats will have the same intensity regardless the amplitude. This makes binaural beats a better choice for someone with hearing loss in one or both ears. Though the tone is heard more quietly, the frequencies are still perceived and the desired result achieved.
Some people find the tones and the beats effective but annoying. With binaural beats, you can mask the tones with white or pink noise. This does not decrease the effectiveness. With monaural beats, however, masking the tones eliminates the perception of beating and does away with the frequency-following response.
Binaural beats are believed to originate in the superior olivary nucleus, a part of the brain stem that responds to input from both ears and makes it possible for animals and humans alike to locate sources of sound and track moving sounds. However, researchers began to notice that these sounds influenced the patient’s brain in ways other than just auditory. When the perceived beat frequency corresponds to delta, theta, alpha, beta or gamma brainwave frequencies, it becomes possible to train the brainwaves to a higher or lower frequency which results in a change in mood or concentration level. This change depends on which wave the frequency is closest to.
In deciding which state of mind you’re trying to alter, you must first know which waves affect each mood. Gamma waves are associated with higher mental activity, including perception, problem solving, fear and consciousness and are perceived at frequencies greater than 40 hertz. Beta waves are usually higher in active people. They are related to busy or anxious thinking, active concentration, arousal and cognition. They are usually at a frequency between 13 and 40 hertz. Alpha waves are correlated with relaxation while awake as well as pre-sleep and pre-waking drowsiness and are measured between 7 and 13 hertz. Theta waves usually control dreams, deep meditation and REM sleep and are perceived between four and seven hertz. Delta waves are associated with deep, dreamless sleep and loss of body awareness and are measured at less than four hertz.
A third method of brainwave entrainment was discovered and studied beginning around 1981 by Arturo Manns. Before this method was discovered, most studies were done on light stimulus rather than auditory. The method was found to be more effective than both binaural and monaural beats and is comprised of a series of evenly spaced tones. It does not require the use of headphones and falls under the category of brainwave entrainment rather than cortical evoked response. This method is known as “Isochronic Tones” or “Isochronic Beats”.
Isochronic tones have been used to treat TMJ and insomnia, among other things. Dentists have found that isochronic beats can be used to prevent a patient from getting TMJ during dental procedures also.
Isochronic tones also have their own shortcomings. Both tones must be the same volume and the volume must be loud enough to detect the difference in tone. But because one can use them without headphones they are found to be easier and more effective.
There are new technologies combining isochronic beats with photic stimulation. This is known as audio-video entrainment. It appears to be more effective because there is more than one source of stimulation to the brain.
In the 80s, Dr. Norman Shealy and Dr. Glen Solomon researched entrainment for headache relief, serotonin and HGH release as well as relaxation and found it to be effective. In 1980 Tsuyoshi Inouye and associates at the Department of Neuropsychiatry at Osaka University Medical School in Japan found photic stimulation produced “cerebral synchronization” in more than five thousand patients. In 1981, Michael Hutchison wrote a book called MegaBrain outlining the possible uses of brainwave entrainment while Arturo Manns published a study showing the effectiveness of isochronic tones which was later confirmed by David Siever.
During the 90s Dr. Russell and Dr. Carter studied the potential use of brainwave entrainment with Attention Deficit Disorder and other learning disorders. They researched its effectiveness on PMS, chronic pain, chronic fatigue, depression and hypertension.
Today there are machines, like the Dream Machine, and computer programs, such as SBaGen, that allow you to build your own entrainment sequence based on what you feel needs to be changed in your own brain. By listening to the beats it’s possible to change your state of mind completely from making it easier for you to concentrate at work to allowing you to calm yourself in periods of high stress. In short, brainwave entrainment can give you a better outlook on life.