A Brief History of Brainwave Entrainment
This article provides a brief history of brainwave entrainment.
Brainwave entrainment was first identified in 1934, although its effects had been noted as early as Ptolemy.
Not long after the discovery of the Alpha brainwave by Hans Berger in 1929, researchers found that the strength of the wave could be "driven" beyond its natural frequency using flickering lights. This is called "Photic Driving," which is another word for brainwave entrainment using photic (light) stimulation. In 1942, Dempsey and Morison discovered that repetitive tactile stimulation could also produce entrainment and in 1959, Dr. Chatrian observed auditory entrainment in response to clicks at a frequency of 15 per second.
By the 1960s, entrainment started to become a tool rather than a phenomenon of the brain. Anesthesiologist M.S. Sadove, MD, used photic stimulation to reduce the amount of anesthesia needed for surgery. Bernard Margolis published an article on brainwave entrainment used during dental procedures, noting less anesthesia required, less gagging, less bleeding and a general reduction in anxiety.
In a 1973 issue of Scientific American, Dr. Gerald Oster examined how combining 2 pure tones resulted in a rhythmic beat which he called Binaural and Monaural beats. In comparing Binaural beats against Monaural beats, Oster noted that Monaural beats were shown to elicit extremely strong cortical responses, which is the electrical activity responsible for entrainment. Oster concluded that while Binaural Beats produced lesser neural response (because the depth of a Binaural Beat is only 3db or 1/10 the volume of a whisper), they could be useful in diagnosing certain neurological disorders.
In the 1980s, studies continued with Dr. Norman Shealy, Dr. Glen Solomon and others researching entrainment for headache relief, serotonin and HGH release, as well as general relaxation. Michael Hutchison wrote his landmark book MegaBrain in 1981, outlining the many possible uses of entrainment from meditation to super-learning. In 1980, Tsuyoshi Inouye and associates at the Department of Neuropsychiatry at Osaka University Medical School in Japan found that photic stimulation produced "cerebral synchronization." Dr. Norman Shealy later confirmed the effect, finding that photic stimulation produced synchronization in more than 5,000 patients. In 1984, Dr. Brockopp analyzed audio-visual brain stimulation and in particular hemispheric synchronization during EEG monitoring. He said "By inducing hemispheric coherence the machine can contribute to improved intellectual functioning of the brain."
In 1981, Arturo Manns published a study showing the effectiveness of Isochronic Tones. This was later confirmed by others such as David Siever. This entrainment method was perceived to be more effective than Binaural and even Monaural beats, and combined use of the methods was found to bring about greater results.
Studies continued into the 90's with researchers such as Dr. Russell, Dr. Carter and others who explored the vast potential of using entrainment with ADD and learning disorders. Research has also been conducted into PMS, Chronic Fatigue, Chronic Pain, Depression, Hypertension and a number of other disorders. Steady research continues today with the work of Dr. Thomas Budzynski, David Siever, psychologist Michael Joyce and many others. The results of entrainment have been so promising that many modern clinical EEG units come with entrainment devices.
In total, there are over 75 years of solid research behind brainwave entrainment.
Despite this, the average individual still has little idea that this branch of science even exists. Perhaps this is down to the almost unbelievable idea that music can affect the brain so dramatically. It's common for most people to be skeptical about brainwave entrainment until they experience it for themselves.
Yet still, the word about brainwave entrainment is spreading - and every day, more psychologists, mental health clinics, coaches, teachers and professionals are discovering entrainment, and uncovering the powerful impact it can have for both themselves and their clients.
Responses to Clicks from the Human Brain: Some Depth Electrographic Observations, Gian Emilio Chatrian, M.D., Magnus C. Petersen, M.D., and Jorge A. Lazarte, M.D. - Rochester State Hospital (1959).
Academic Performance Enhancement with Photic Stimulation and EDR Feedback, Thomas Budzynski, Ph.D., John Jordy, M.Ed., Helen Kogan Budzynski, Ph.D., Hsin-Yi Tang, M.S., and Keith Claypoole, Ph.D., Journal of Neurotherapy
Repeated stimulation induced neuronal activation (SINA), with cognitive and behavioral functioning changes in ADHD children., Harold Russell, Ph.D., Journal of Neurotherapy
A Comparison of Depths of Relaxation Produced by Various Techniques and Neurotransmitters by Brainwave Entrainment, Shealy, N., Cady, R., Cox, R., Liss, S., Clossen, W., Veehoff, D., Shealy and Forest Institute of Professional Psychology A study done for Comprehensive Health Care.
Auditory beats in the brain., Oster, G., Scientific American, 229, 94-102.
Isochronic Tones and Brainwave Entrainment, David Siever, C.E.T.
The central effects of rhythmic sensory stimulation., Walter, V. J. & Walter, W. G., Electroencephalography and Clinical Neurophysiology, 1, 57-86
Visual Evoked Responses Elicited by Rapid Stimulation, Kinney, J.A., McKay, C., Mensch, Lurisa, Encephalography and Clinical Neurophysiology, Vol 34: 7-13
The Interaction of Certain Spontaneous and Induced Cortical Potentials, Dempsey, E., Morison, R., American Journal of Physiology, 135, 310-307
Neurochemical Responses to Cranial Electrical Stimulation and Photo-Stimulation via Brain Wave Synchronization., Dr. Roger K. Cady, Dr. Norman Shealy, Study performed by the Shealy Institute of Comprehensive Health Care, Springfield, Missouri, 1990
The Application of Audiostimulation and Electromyographic Biofeedback to Bruxism and Myofascial Pain-Dysfunction Syndrome, Dr. Arturo Manns, Miralles, R., Adrian, H., Oral Surgery, 1981, Vol. 52