Articles and Research on Rhythmic Entrainment Intervention (REI)

Blending Ancient Techniques with Modern Research Findings


By Jeff Strong Director, REI Institute

Published in Open Ear Journal, 10/02


From the shamans of Outer Mongolia to the Manbos of the Caribbean, rhythm has been used for thousands of years as a means to create and maintain health and well being. There is hardly a place on this planet where rhythm, usually in the form of drumming, hasn't embedded itself into the very fabric of society - often becoming an essential part of creating and maintaining spiritual, mental, and physical health. In spite of the many differences among ancient societies, very few differences emerged among their therapeutic rhythm techniques.


In fact, only three core approaches developed: Community drumming, shamanic drumming, and rhythm-healing. Community drumming focuses on shared rhythm-making and the effects of playing an instrument with other people, whereas shamanic drumming and rhythm-healing employ very specialized rhythmic techniques designed to have a prescribed effect on the listener.


Rhythm-healing is an ancient approach that uses complex rhythms that are designed to influence the internal rhythms of the individual. Rhythm-healing is based upon the theory that specialized rhythmic drumming patterns can influence the internal rhythmic patterns of the individual and correct those which are thought to be out of synch and causing illness.


Specific rhythms, when administered correctly, may be used to affect the emotions, pain levels, nervous system function, and organ function. This technique has been used for thousands of years to treat a variety of conditions. Rhythm-healing has been practiced by indigenous societies in West Africa, Central America, North America, South America, and the Caribbean. Rhythm-healing relies on a key part of our biology: External rhythms can influence the body's own internal rhythms.


This is technically called entrainment and is a basic part of our biological make-up. Entrainment is simply the synchronization of two or more rhythmic cycles and is a universal force in nature. All that is required are two rhythmic cycles that are similar. The easiest way to see entrainment is when traveling across several time zones in a day. This causes us to be out of synch with the day/night cycle where we experience fatigue, disorientation, irritability, and sleep problems. These symptoms disappear after a few days because we entrain to our new day/night cycle. There are many techniques available that employ entrainment as a means of altering our internal rhythms, from cranial-sacral therapy to "sound wave" and vibrational technologies. In fact, much of the "healing music" available today uses external rhythms to attempt to slow the heartbeat of the listener.


Like Rhythm-healing, Shamanic drumming is an ancient, almost universally used technique. This technique is part of the larger shamanic healing tradition. Shamanism is considered the world's oldest organized healing system - estimated to be between 20,000 and 30,000 years old - and can be found in nearly every pocket of the earth. In his book, The Way of the Shaman, Michael Harner writes that shamanic techniques are "strikingly similar the world over, even for peoples whose cultures are quite different in other respects, and who have been separated by oceans and continents for tens of thousands of years." The core aspect of shamanic drumming is the use of a repetitive rhythm to affect the listener's state of consciousness.


Traditionally, a four-beat-per-second rhythm is played on a drum in order to "drive" the listener's consciousness into the theta range (theta consciousness exists between 4 and 7 cycles per second and is associated with a meditative state). This approach relies on another form of entrainment and a core aspect of the human nervous system: An auditory stimulus can influence brain wave states. More specifically, a rhythm played at a specific tempo (frequency) can induce that same frequency in the brain. This is called auditory driving and is the basis for a myriad of consciousness-altering technologies available, from binaural beat technology to "brainwave suites".


After studying, first-hand, these two rhythmic techniques (first with a Shango Baptist healer and then a Celtic shaman), I became intrigued by the possibilities of integrating them into Western health-care practices. Because the traditional rituals associated with the Shamanic and Rhythm-healing techniques are so foreign to people in the West, they were removed leaving the core elements of the rhythms are their effects in the nervous system.


After much experimentation, we discovered that increasing the speed and complexity of the rhythms would calm people with severe anxiety within minutes and often facilitate overall changes in aberrant behaviors - such as those seen in people with autism, schizophrenia, and ADD - through repeated exposure to the rhythmic patterns. This experimentation - which lasted for several years - gave birth to the technique subsequently called Rhythmic Entrainment Intervention (REI).


REI is unique to traditional rhythmic approaches in two ways: First, rather than focusing primarily on the theta frequency rhythms, as nearly all traditional techniques do, most REI rhythms are played within the alpha frequency (alpha is a wakeful state of conscious associated with a relaxed state of mind). The second unique aspect of REI is that each of the specialized rhythms has been designed to stimulate the brain in positive ways.


The specialized rhythms are important in two ways: First, in order to induce an alpha state in the listener, the rhythms can't be predictable otherwise the nervous system becomes habituated to the rhythms and won't entrain to them (this isn't a problem for inducing theta states which is why the traditional techniques worked even though the rhythms were often very simple). The two ways around this include either constantly changing the rhythm or using rhythms that can't be figured out very easily (if at all). Even the most trained musicians have a difficult time counting a 21 beat rhythm going by at 8 beats per second. The second reason for these specialized, complex rhythms is that our research has shown that different rhythmic patterns effect different symptoms.


For example, we found that a rhythm in the time signature 21/16 works well to help reduce self-stimulatory behaviors in people with autism. With the development of REI came the formation of the REI Institute. The REI Institute's goal is to study rhythm and its effects on the human nervous system.

Our first formal study was conducted in 1994 in a public school outside of St. Paul, Minnesota. In this study 16 elementary-age children with autism spectrum disorder were each given a 20 minute recording of REI rhythms (each recording was created specifically for each child based upon observations of their responses to various rhythms).


Each subject listened to their recording depending on their daily schedule and each was assessed in two areas: immediate calming effects and long-term behavioral change. The results for immediate calming showed that 14 of 16 subjects were calmed most of the time within a couple of minutes. It didn't matter whether the listener liked the music or not, though nearly all did.


As far as long-term overall changes the results showed that the subjects that heard the recording at least three times per week over the course of the study had significant, observable improvements in a variety of behavioral and cognitive areas. These areas included aggression, anxiety, self-stimulating behaviors, language skills (both expressive and receptive), social interaction, and eye contact.


This study led to numerous double-blind, placebo-controlled studies, the results of which corresponded to the findings of the pilot study. Anxiety reduction was almost immediate and universal (about 90% effective). Long-term change varied from person to person with significant improvement in the same areas as seen in the original study - though often not as profound. The reason for the reduced overall improvement is due to the fact that the controlled studies used a generalized recording of REI Rhythms instead of the custom-made recording that was created for each subject in the original study. Subsequent client studies - ten years worth - have born out this theory.


Custom-made CDs with rhythms specifically chosen for the individual are more effective than a single recording created for a general condition. From this body of research the REI Institute offers both a custom CD program, called the REI Program, and several generalized CDs. The REI Program consists of two CDs of specific rhythmic patterns recorded for each client based on a comprehensive intake interview and questionnaire process.


The REI Institute staff currently performs this process, but beginning this year will be conducted by trained REI Therapy Program providers around the country. Once the custom-made CDs are created, the REI Program is then implemented in the family's home by the client's caregiver (or the client himself if he is capable - as with ADD adults). This recording is played once a day for 8-12 weeks.


This program often results in long-term behavior and cognitive change for people with autism, ADD, CAPD, and learning disabilities. The generalized CDs that we created include two basic lines: the Rhythmic Entrainment Intervention series and the Rhythms for Health series.


The Rhythmic Entrainment Intervention series CDs draws directly from the controlled studies on people with autism and ADD and include: Rhythms for Learning and Calming Rhythms 2. Rhythms for Learning is based on the finding from our ADD studies and is designed to increased the ability to focus attention. Calming Rhythms 2 was created from the results of our autism and ADD studies to help reduce anxiety.


The Rhythms for Health series was created for general stress reduction and energetic health. This series currently includes two CDs: Calm Your Mind and Revitalize Your Body. Calm Your Mind is as based on the approach used to make Calming Rhythms 2 as well as the traditional consciousness-altering effects of Shamanic drumming. This CD consists of 3 tracks the first of which uses alpha frequency rhythms to create a "relaxed alert" state in the listener. The second track uses alpha and theta frequency rhythms intended to help the listener shift their attention between alpha and theta. This often results in an increased ability to concentrate. The last track on this CD is intended to help with meditation and problem-solving. This track uses rhythms in the middle theta range combined with rhythms performed within upper delta to create a deeply relaxed state.


Revitalize Your Body is based on a separate line of study into the effects of musical rhythm on the Chinese acupuncture meridians. This CD is designed to stimulate and balance these energetic centers. The ancient rhythm techniques, with minor adjustments to account for our changing world, have held up well to modern research and continue to inform the development of new CDs and approaches. With all the high-tech health-care practices being developed in today's world, it can be comforting knowing that ancient, low-tech approaches can still find a place and be useful.

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