An Abbreviated History of Syntonics and Phototherapy

Light has been used as medicine from ancient times. Egyptians filtered sunlight light through precious gems, Greeks built solarium cities in high mountains to harness ultra-violet light for healing tuberculosis, and red light was used to quell the effects of smallpox virus.

The second Nobel Prize in Physiology of Medicine was awarded in 1903 to Niels Ryberg Finsen, M.D., “in recognition of his contribution to the treatment of diseases, especially lupus vulgaris, with concentrated light radiation, whereby he opened a whole new avenue for medical science.”

Other practitioners in the late 19th and early 20th centuries such as Babbitt, Pleasanton, Pancoast, Loeb and Dinshah also applied color on the skin as a non-intrusive treatment for health problems. Also, at that time, it was first discovered that light entering the eyes not only served vision but also traveled to brain regions not related to eyesight.

Use of selected light frequencies in optometric practice began in the early 1920’s when H. Riley Spitler, D.O.S., M.D., M.S., Ph.D., discovered that light and color delivered through the eyes played a key role in controlling biological development and function. Spitler concluded that many systemic, mental, emotional and visual ailments were due to imbalances in the autonomic nervous and endocrine systems.

He named this new clinical science Syntonics – from “syntony”, to bring into balance – wherein frequencies of light applied through the eyes are used to rebalance the body’s regulatory centers thereby correcting visual dysfunctions at their source. His model suggests that red (low energy, long wavelength) at one end of the visible spectrum stimulates the sympathetic nervous system, green (middle frequencies) yields physiological balance, and blue/indigo (high energy, fast frequencies) activates the parasympathetic nervous system.

In 1933 Spitler, a past president of the Ohio State Board of Optometry and past first vice-president of the American Optometric Association, established the College of Syntonic Optometry to encourage education and research related to the therapeutic application of light and color to the visual system.

In 1941 he published his thesis: THE SYNTONIC PRINCIPLE: Its Relation to Health and Ocular Problems. This included a survey of clinical results from syntonic practitioners: Syntonic Effectivity: A Statistical Compilation of Ocular Anomalies Handled by Applying the Syntonic Principle. This study showed that of 3067 individuals, 2791 (90.7%) taking syntonic treatment responded positively.

After Spitler’s death in the 1960’s, Charles Butts developed the BASIC SYNTONIC COURSE, an optometric diagnostic workup and treatment regimen in which patients were diagnosed according to symptoms using a specific case history, the O.E.P. “21 points,” pupil responses, central visual fields and other tests of eye teaming and motility.

Advanced approaches based on earlier descriptions of syntonic applications, current scientific research and modern technology encourage an evolving phototherapy and a wider range of clinical application.


THE SYNTONIC PRINCIPLE: Its Relation to Health and Ocular Problems, by Harry Reily Spitler was published by the College of Syntonic Optometry in 1941. Covers the thesis from which the practice of syntonic phototherapy was established. Available through the College Of Syntonic Optometry.

LIGHT MEDICINE OF THE FUTURE, by Jacob Liberman, Bear and Co., Santa Fe, NM, 1991, covers medical and psychological uses of light and contains an extensive bibliography. It is a must-read for anyone interested in the subject.

LIGHT YEARS AHEAD: The Illustrated Guide to Full Spectrum and Colored Light in Mindbody Healing, Brian Breiling and Bethany ArgIsle, editors, Celestial Press, Berkeley, CA, 1996, is a compilation of the Light Years Ahead conference held in 1992 in San Jose, California. With chapters written by leading practioners, it is one of the best texts to get an overview of light therapies and light technologies in use at that time.

Tribute to Dr. Stanley Levine, CSO Trustee, A Man of Action A scholarship is being established for a fourth year Optometry student in Dr. Levine’s honor.  Details to be announced soon

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