new book coming by Valerie Dejean
Tomatis, Autism and Sensory Integration

.Tomatis With the right ear eliminated, (the left ear leading) the voice was flat full blown stuttering resulted the same thing with other musicians, for example the violinist could no-longer control his fingers. (Ear not only controlled the voice but it influenced the motor functions)

W ith the left ear suppressed, (the right ear leading) the voice became lighter, more timbre and higher pitched. With the right ear eliminated, (the left ear leading) the voice was flat, without tone or timbre and badly produced, it became filled with hesitations, with "ah's" and more prolonged. Even full blown stuttering resulted.

He also found the same thing with other musicians, for example the violinist could no-longer control his fingers. (Ear not only controlled the voice but it influenced the motor functions) In other words Tomatis observed that in terms of audio-vocal control the two ears were not being used in the same way. He found that the right ear "measures the higher frequencies," while the left ear is more attuned to the lower pitched frequencies. (P 52) This phenomenon is fraught with consequences. The right ear may process wavelengths from 35 to 70 centimeters, while the left ear the wavelength may range from 35 to 140 meters. The larynx is really two organs and they are not symmetrical.

The passage of nerve impulses from the cortex (via the vagus nerve) to the lining of the left larynx has a longer route than the pathway from the cortex to the right larynx. This corresponds to the right ear is closer to the organ of speech than the left ear. Vagus is the wanderer, wanders more on the left side. There are fewer stages involved from the right ear Sound travels from the Right ear to the Left Hemisphere Auditory Center - then to the Left Hemisphere laryngeal motor area - speech muscles - mouth and back to right ear.

Left ear - Right Hemisphere Auditory Center - crosses the corpus collusum to the Left Hemispheres laryngeal motor area - speech muscles - mouth to left ear. These differences (length of the pathway and crossing over at the corpus collusum) represent a delay of many milliseconds. Tomatis saw this as an absolute; all great singer and musicians were "right eared" p51. The right ear has an advantage in that it receives its information more rapidly.

T omatis concluded that "we listen with both ears - the lead ear (right) focuses on the precise sounds, while the other provides the general picture of the sonic background. Much like with vision. When the eye focuses on the distant landscape without focusing on anything in particular the dominant eye doesn't enter the picture. Yet when we read the dominant eye takes a central control role.

The conclusions that Tomatis drew were that there is a preferential ear, designated to execute the more special and more precise control functions. He call this the Leading ear and using the analogy of the leading eye, it was the one that took aim, in that the speaker takes aim at the sounds he emits. 1954 Tomatis developed the gate for the electronic ear and he developed a mechanism of right ear control, which was called the balance. The electronic ear now included these principles of audio-vocal control via the gate and right-ear balance.

Research on Stuttering - delayed feedback

Tomatis noticed in his work with singers and actors in particular that if he interrupted the feedback of the audio-vocal control of their right ear, they would often develop dysfluency or stuttering. He speculated as why interrupting this control would create stuttering and if a similar phenomenon existed in the true stutter. He started to explore the relationship of the loss of a controlling ear with stuttering. The way this is researched is that a speaker listens to himself through headphones while simultaneously he speaks into a microphone. It is possible to manipulate the feedback of the voice by lengthening the time it comes back to the ear. This created a time lag between the utterance and the feedback.

The difference between a well lateralized Audio-phonatory circuit and a poorly lateralized one is that a delay is introduced by the extra transfer of information. Transfer of information across the cerebral hemispheres can be .05 seconds. When you add an extra step in the equation you increase the time for this transfer. He observed that there were periods of latency before stuttering was induced and that this latency period differed between languages. For example French was .15 while English was .20. This also coincided with the length of time it takes to pronounce a vocal unit (syllable) with the language. Tomatis started to evaluate all the stutters his colleagues could refer to him and what he observed was that the stutterers had not established a directing ear. They were in effect creating a delay because of a lack of auditory lateralization. If he could help these individuals to establish a directing ear and it could be either ear, then their stuttering would improve.

Language and Laterality

Tomatis' discoveries about the directing role of the right ear lead him to research the laterization of auditory function. We need two ears to locate the direction of sound but why the need to lateralized control as he observed in the leading ear? Animals are not lateralized so to speak, yet man seems to have been lateralized since the earliest times. Wherever man has arisen as a rule his laterality has been largely right handed. No nation or culture of left-handed humans has evolved. On a more lofty scale Tomatis came to believe that laterality was a key to man's humanization and that without it there would be no language. What was undetermined was did laterality shape language or whether language is at the origin of laterality. Tomatis felt that one couldn't exist without the other. He felt that it was probably a parallel evolution that was most likely.

A lot of the language research of the day was on deaf mutes, particularly those of the 19th century before the advent of sign language. So these individuals not only didn't hear or speak, but they had no language structure so to speak. There is a very high degree of manual ambidexterity in deaf-mutes and this was more so before the advent of sign language. In studies of deaf-mutes before the era of sign language and specialized schools, (19th century) 100% of them were ambidextrous.

There is a greater degree of poor laterization in developmental and language delays. Tomatis felt that language and laterality went hand in hand. The development of language imposed laterality as observed in the deaf-mutes. And the interruption of laterality dissolved language as he observed in his singers. In his experiments with the singers Tomatis noticed that when he suppressed the leading ear, he observed not only dissolution in their language but also in their rhythm and the spatial organization of language. Laterality was a hotly debated topic in the times leading to Tomatis' theories as well as after.

Much of the research on laterality was between the theories of localization and theories of association. (Broca and Wernicke). It was the work of Jackson and Henry Head that explained "disorders of the nervous system have to be considered as reversals of evolution, that is, as dissolutions" Our modern human scaffolding appears to be a secondary acquisition built upon an ancient structure, This more modern piece while prodigious, is yet more fragile and ready to collapse.

The evolution of the nervous system moves from

  • Automatism toward voluntary action

  • Simple to complex

  • Rigidly organized toward the more flexible

    • Laterality and Language being our newest to evolve are most vulnerable yet enable us to makes our most automatic acts, the most faithful executors of our will.

    Laterality and Language

    Language and the need to control it created the need to construct laterality. Lateralization, via a leading ear, gives us the ability - the first sensory control of our self-listening. Therefore it makes us conscious of our language and breaks us away from a purely automatic process and therefore can only lead to a purely expressive language (P 143 E and L)

    Laterality and Control

    This control occurs at the first level of our sensory awareness and is known as gnosis, as distinct from unconscious or, to some extent, automatic perception. Any act cybernetically dependent on this control is designated praxis, or acquired act, as distinct from instinctive, involuntary acts. We can start to hear ourselves speak. Birds do not hear themselves sing. They have no relationship to their voice. It is this audio-vocal control, this self-listening loop, which allows us to form a relationship to our own voices and allow us to develop the type of control that is needed to use our voice as a tool to communicate symbolic information.

    The interaction between thought and language is mediated through this audio-vocal mechanism and laterality is what allows us the control over it. It creates the possibility to be symbolic. Therefore, both knowledge and conscious gesture must be distinguished, and they depend upon unilateral control. Tomatis explains this functional asymmetry as a question of control rather than dominance.

    Tomatis would say that the dominant side should more correctly be called the executor while the opposite side should be called the integrator. They have different activities. The dominant side is organized out of the non-dominant sides integrating response. Tomatis defines a gnosial (knowing) and praxial (acting), the left, and a referential brain, the right, whose main role is to allow us to work out that gnosis and praxis. Thus a right-hander, for example, executes all his praxial, learned acts under the control of his right gnosis, including in this regulation the gestures of the left side of the body. So language, knowing, and action all come under unilateral control, in order to allow us consciousness, awareness, and control about what we are doing. Tomatis identified that it was a control mechanism that was lateralized. Not the functions themselves. For example by challenging the control of the right ear (left praxial) in a violin he would affect the fingering of the left hand yet for another instrument it could be the right hand. Relationship between Listening and the Body Concurrent with all this, Tomatis started to notice physical behavior of patients varied according to type of listening. Violinist- cut high frequencies and he had difficulty shifting his fingering while by adding high frequencies his playing improved. Motor Control. By altering a singer's audio-vocal control, it actually transformed his way of breathing and his physical make-up. He observed postural changes. Held their head differently. Stood straighter.

    With the feedback of the Electronic Ear these changes became long lasting in many cases permanent. He saw clients increase 4-5 inches in the measurement around their thorax. He started to investigate the concept that listening controlled more functions than just the voice and this eventually lead him to evaluating the vestibular functions of the inner ear. This part of the work took him twenty years and eventually leads to the concept of the integrators.

    E ar and the Skin: In 1950 Tomatis treated 70 stutters by training them for right ear dominance. He had very good success with some responding with only a few sessions and others requiring up to a years treatment. All maintained their progress in follow-up evaluations. He would have thought he had the whole answer in the hypothesis of the directing right ear if it wasn't for two clients who failed to respond to treatment.

    The only difference he could find was in the color of their hair and skin. These unsuccessful clients had blond hair and blue eyes where as the successful clients were all darker! He pondered this wondering if it was a particular sensitivity in play. It was not an auditory sensitivity, as he hadn't recorded it on the audiogram, so he contemplated skin sensitivity. Tomatis has always contemplated the relationship between the skin and the ear so this wasn't a funny place for him to look. He contends that the skin is a piece of undifferentiated ear. In Vers L'Ecoute Humaine which hasn't been translated he contends that phylogenticaly the ear preceded the nervous system and further that he sensory cells found in the skin (Meissner's Pacinian, Krause, Merkel's) are differentiated cells of corti and through this evolution (sensory cells of corti towards cutaneous hair cells of the skin) that he developed the hypothesis the we listen with our skin.

    So he created a type of cutaneous audiogram, which he called a dermogram. He found that with the darker skinned individuals that they registered sounds at 10-15 decibels, while the two fair skinned individuals registered sounds at 80-100 decibels. There wouldn't perceive until a higher level of stimulation and then they would over-react. When we speak, we also have to listen to ourselves. This is part of the audio-vocal feedback loop that is controlled by the directing ear. The ear regulates the intensity, volume, duration, however it doesn't control the flow.

    When we talk an acoustic stream comes out of our bodies in successive waves, shaped in its form and volume by our articulation and poured over us. Cutaneous sensitivity and the quality of phonatory control are in constant relation to one another. So if the skin lacks sensitivity the whole process of audio-vocal control is endangered. If you isolate the body, by putting the head in a baffle for example, you immediately disturb the whole regulation. The most persistent stutters were particularly deprived of the dermal control mechanism. The treatment of these kinds of stutters required helping them to learn to sense the flow of sound over their skin.

    As Tomatis more eloquently put it "the person must learn to use his body like a musical instrument.... a cutaneous keyboard. He also made another interesting observation about these "recalcitrant stutters". He didn't feel that it was that they couldn't hear the sounds but rather they couldn't defend against them and would therefore shut down until they were overwhelmed and presented with a negative reaction. "Their ear and by extension the skin had an all or nothing perception. They experience the sound as an attack and the speech flow pouring over their bodies caused stress" (109CE)

    Where on the other hand people with sensitivity in the 5-10db range were able to adapt and defend against sound better. They had a bettor control mechanism. They could regulate between their skin and their ear in a more adaptive fashion. He described the reaction in the fair skinned people "as a timidity which to be strictly accurate, has no relationship to a person's emotional nature." Sound like anything familiar? Now to be clear, Tomatis isn't saying that fair skinned people who stutter have more difficulty listening than dark skinned people, I believe it was an observation that lead him to look at the role of the skin in the mechanism of the control speech.