History of Auditory/Visual Stimulation
- Brainwave Entrainment -
The science of auditory and visual stimulation
AVS is related to the study and use of biofeedback; a training procedure that can enable a person to alter physiological responses to induce a desired state of mind. However, the application of AVS is quite distinct from biofeedback. In biofeedback, the object for the individual is to deliberately try to calm or train mental and physiological activity.
With AVS, passive inducement occurs without the conscious effort of the individual. The frequencies of light and sound can be utilized for relaxation or stimulation purposes without the side-effects associated with other common approaches.
How AVS works
The induction into higher arousal states induced by higher frequencies of our broad-spectrum white LED lights is theorized to provide enhanced mental activity, which can result in cognitive improvement. The induction to lower states of mental activity through specific lower frequency rates has been found to reduce feelings of anxiety and stress thereby promoting feelings of calmness and deep relaxation, allowing the mind to operate more efficiently with greater clarity.
How AVS technology is applied
Auditory and visual stimulation is introduced primarily through the optic nerve and ears by means of computerized technology. This technology is applied to the individual through the use of specially designed glasses inset with light-emitting diodes (LEDs) set at specific angles and distances from the eye to optimize desired effect.
These lights flash at predetermined frequencies, and are coupled with specific tones that are received through headphones. The light emitting from the glasses and rate of the flicker introduced by way of the optic nerve creates a matching effect, or induction, between the mind and the set rate of flickering, thereby moving the mind to either more energetic or into deeply relaxing states. Frequencies are determined by the preferred outcome.
Frequency Following Response
The induction method by which this occurs is known as Frequency Following Response (FFR). Through this natural response mechanism, the mind matches the corresponding visual and auditory stimulus. Two common examples demonstrating a typical relaxation response are when gazing into a gently flickering flame, or the effect of soothing music upon the listener.
The World’s First Commercial Brainwave Synchronizer, circa 1959-1974
The brain wave synchronizer pictured above (Model #4 out of about 7-8 models) was likely produced in the mid-sixties. Though crude by today’s standards, the effect of this device can still be felt today.
The Brain Wave Sychronizer Photic Stimulator in action
The Journal of the American Medical Association published an article for the first time on the Brain Wave Synchronizer in March, 1959.
A Brief Background of Photic Stimulation
The earliest mention of photic stimulation actually dates back many centuries with the mention of spinning light wheels. Early in the 20th century scientists developed the first EEG instruments sensitive enough to measure the minute electrical brainwave activity.
In 1924 German psychiatrist Hans Berger developed the first electroencephalography device (EEG) and was the first to identify the fact that the brain produces electrical output in a wave form we refer to as brainwaves. In 1929, he published the first of 23 research papers on his results much to the derision of the German medical community. At this time the idea that the brain produces electrical output was completely outside the boundaries of the believable.
However, soon after the discovery of brainwaves, early experiments determined that these wave form patterns could be altered by strobes of light blinking in the alpha brainwave frequency range. This became known as photic driving.
Dr. William Kroger was the first to publish results on photic stimulation. The US military in the 1950’s asked Dr. Kroger to study why servicemen staring at radar blips would go into trance. It turns out these blips were appearing at approximately 10 per second, or 10Hz, which is in the alpha brainwave range. Dr. Kroger teamed up with Sidney Schneider to produce devices as the one pictured above. These devices were manufactured from 1959 through 1974 at several times the expense of today’s modern devices.
In the journal Anesthesiology, Bause, 2010 reflects on the history of the Brain Wave Synchronizer:
After observing how some radar technicians had become “transfixed” by rhythmic flashing dots on their radar screens, inventor Sidney Schneider designed his Brain Wave Synchronizer (BWS) to hypnotize by visually stimulating subjects at frequencies mimicking those of their alpha, beta, or delta brainwaves. In 1959 Schneider and hypnotist-obstetrician William Kroger, M.D., published their use of the BWS in prenatal classes for thousands of women prior to its use as an “electronic aid for hypnotic induction” during labor and delivery [Kroger & Schneider, 1959]. Four years later, Chicago anesthesiologist Max S. Sadove, M.D., published his work on how BWS-induced hypnosis could reduce anesthetic agent requirements during general anesthesia [Sandove, 1963].