Auditory stimulation programs are alternative therapies which stimulate the brain by manipulating the sounds of music and/or voice.
The original auditory stimulation program was developed by Dr. Alfred Tomatis (M.D.-ENT) in the 1960s. He established a link between how we listen and how we speak which is now well-known as the auditory feedback loop.
Dr. Alfred Tomatis also pointed out a distinction between hearing, which is the passive reception of sounds, and listening, which involves active psychological and emotional processing of sounds . Alfred Tomatis developed a proprietary device called the “Electronic Ear.” This technology contains many parameters customized to each individual and specifically designed for the application of the Tomatis Method.
Dynamic Filter versus Regular Filter
The first main parameter of the Tomatis Method is “the dynamic filter” also called “electronic gating.” This filter creates sound contrast effects to stimulate the brain. The timbre and intensity of the sound message are modified alternately without affecting rhythm or melody. These contrasts are meant to surprise the brain, increasing attention and developing a state of optimal listening. The Listening Fitness Method (LIFT), developed by a student of Dr Alfred Tomatis, Paul Madaule, is also equipped with a similar filter. The Forbrain headset, is equipped with a similar dynamic effect to filter the user’s voice.
Finally, the Auditory Integration Training from Dr Guy Berard, uses a similar sound treatment, but with this method, the effect is recorded on a CD and does not involve active processing.
Listen to a piece of music treated with this dynamic effect: listen
Listen to a voice recording treated with this dynamic effect: listen
Many other auditory stimulation programs don’t provide dynamic filters which require specific proprietary equipment, but focus instead on music frequencies and rhythms. These include The Listening Program from Alex Doman (Advanced Brain Technology), whose father was trained by Dr. Tomatis. The Listening Program uses pre-filtered music with specific targeted frequency ranges to stimulate the brain. Another program called The Therapeutic listening (Vital Links) from Sheila Frick, focuses on the rhythm of the music.
Bone conduction
The second parameter of the Tomatis Method is the transmission of sound not only through air conduction but also through bone conduction. Bone conduction is the natural way of hearing our own voice. Just plug your ears and say “hello,” and you will feel your own voice vibrating through bone conduction. Alfred Tomatis discovered that transmitting the sound first by bone conduction, thanks to a special vibration at the top of the head, can better prepare the brain to receive information through the air canal. This process gives the brain time to anticipate the arrival of the message and thus facilitates its analysis. This trains the brain to correctly process auditory information.
Some other auditory stimulation programs such as the Integrated Listening System (ILS) from Dr. Ron Minson, are also using bone conduction. In the Tomatis Method, it is possible to individually set this parameter by transmitting the sound through the air canal with a few milliseconds of delay. The listening Program also provides bone conduction headphones as an option.
Forbrain is the only device using only bone conduction to transmit vocal sounds.
Some new tools are customized for specific situations and are now dedicated to transmit filtered music via bone conduction, such as the Dreampad from ILS.
Music vs Voice
A lot of auditory stimulation programs are filtering (with or without a dynamic effect) classical music such as Mozart (the well-known “Mozart Effect” developed by Don Campbell, comes from combining Mozart music with the Tomatis Method). This music is generally well appreciated and has a lot of harmonics, which are good for brain stimulation. Some approaches like the Tomatis Method, Forbrain or the Integrated Listening System, also use the voice of the user as part of the program. The user is asked to speak into a microphone and the voice is filtered and directly retransmitted to the ears. In such a situation, the brain is challenged due to the natural audio-vocal loop, which is modified. This gives the brain a sensory workout. Forbrain is the foremost device using this technique.
Professionals vs Consumers
Many auditory stimulation programs are designed to be implemented by Speech, Language and Occupational therapists. These programs can be customized to an individual’s needs and a professional can adjust the settings for each person accordingly. Once the settings have been established the program can now be used at home. Many of those professional programs also provide solutions for end-users, mainly in the form of preset programs.
Applications
There are numerous applications of these auditory stimulation programs. One of the most common uses is with Autistic children. Other applications include people who have Auditory Processing Disorders, ADD, ADHD, and learning difficulties.
Results
There is a lot of research on the impact of listening programs. For the Tomatis Method alone there are more than 40 studies, some published in peer-reviewed scientific journals, which show positive effects. The fact that protocols and even proprietary equipment differs might explain why there aren’t more scientific papers.
