Tomatis looked at the role of the leading ear in stuttering. This was from his finding that when he masked the leading ear some people with normal phonation they actually started to stutter. This result was not found in all subjects however. He started with the premise the "It was the right ear that controlled speech and stuttering was bound up with the loss of this controlling ear. This lead him to theories of laterality and control of listening that was relevant to stutters but applicable to many other listening disorders. At the same time he became aware of research being done in the United States at Georgetown University by John Lee and John Black. They found by delaying the feedback that someone received from their own voice, by speaking into a microphone, taping the voice, and delaying the feedback, they would elicit stuttering and that this stuttering occurred when the delay reached a specific threshold. Tomatis duplicated this experiment by using a long tube, making holes that corresponded to a one tenth of a second delay. Lee and Black had found that articulation difficulties occurred between one-tenth and two-tenth of a second. Tomatis found very similar results. He postulated that poor lateralization in contrast with good lateralization, introduces an element of delay caused by an extra step in the transfer of information

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STUTTERING

Valerie Dejean, Spectrum Center, Manhattan

THE LEADING EAR AND STUTTERING

As Tomatis continued his research he found that by establishing auto-control by a single ear in a voice that was either disorganized or not yet organized, always produced an improvement, no matter which ear was chosen. Remember his last research was on individuals with good ears, singers and actors. He determined that the coexistence of two auditory receivers can be a troublesome factor.

The next area that Tomatis looked at was the role of the leading ear in stuttering. This was from his finding that when he masked the leading ear some people with normal phonation they actually started to stutter. This result was not found in all subjects however. He started with the premise the "It was the right ear that controlled speech and stuttering was bound up with the loss of this controlling ear. This lead him to theories of laterality and control of listening that was relevant to stutters but applicable to many other listening disorders.

At the same time he became aware of research being done in the United States at Georgetown University by John Lee and John Black. They found by delaying the feedback that someone received from their own voice, by speaking into a microphone, taping the voice, and delaying the feedback, they would elicit stuttering and that this stuttering occurred when the delay reached a specific threshold. Tomatis duplicated this experiment by using a long tube, making holes that corresponded to a one tenth of a second delay. Lee and Black had found that articulation difficulties occurred between one-tenth and two-tenth of a second. Tomatis found very similar results. He postulated that poor lateralization in contrast with good lateralization, introduces an element of delay caused by an extra step in the transfer of information.

Instead of the faster passage from the right ear to the speech centers in the left hemisphere, information from the left ear went to the right hemisphere and then back to the left hemisphere. This transfer can take place between .05 seconds and .4 seconds but varies with the individual. So some people can lose their directing ear and still not stutter. Stuttering appears when it occurs within .1 seconds and .2 seconds with a peek at .15 seconds.

Tomatis also found that the average duration of physiological delay varied according to the language of origin. .15 for the French and .2 for English. Therefore many multilingual speaker can be fluent in English while stutter in French. 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. The 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 a 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'ecout 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 the evolution of the sensory cells of corti towards cutaneous hair cells of the skin support 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. 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 that they couldn't defend against them and would therefor shut down until they were overwhelmed and presented with a negative reaction. "The 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 better 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 as the mechanism to control speech. Tomatis finally came to the belief that ultimately the stutterer does not hear or listen to themselves, and this is because he is incapable of auditory awareness on the level of bone conduction. This doesn't mean that the individual cannot hear through bone conduction, it more that they don't process through bone conduction. When we speak the sound comes out, with the higher sounds thrown out in a straight line, and lower sounds spread out everywhere. (that's one of the reasons why our voice sounds funny in a tape recorder) At the same time the skill vibrates and transmits sound information directly in the ear and down the spinal column directly into the whole body.
Great singers control their voices through bone conduction. Tomatis found in stutters and this is especially true for autistic children that there was a lack of harmony between bone and air conduction, with the latter (bone conduction), always being more sensitive. So these four factors became very important in Tomatis' theories regarding the treatment of listening disorders. By the 1950's he had identified these following principals. The voice can only produce what the ear can hear The leading ear has a role in the establishment of audio-vocal control. The body has an important role in self-listening. Bone conduction plays an important role in self-listening. He called this "audiophonology" which means "to hear oneself speak" He then went on to call it Audio-Psycho-Phonology to include the influence of will. "To listen and to listen to one-self are voluntary acts, recent achievements of evolution, while to hear is purely automatic. Listening is quickly replaced by hearing if any unfortunate experience occurs to break up the marvelous but unsteady functional structure." And he felt that all of these were ultimately associated with laterality.

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Tomatis looked at the role of the leading ear in stuttering. This was from his finding that when he masked the leading ear some people with normal phonation they actually started to stutter. This result was not found in all subjects however. He started with the premise the "It was the right ear that controlled speech and stuttering was bound up with the loss of this controlling ear. This lead him to theories of laterality and control of listening that was relevant to stutters but applicable to many other listening disorders. At the same time he became aware of research being done in the United States at Georgetown University by John Lee and John Black. They found by delaying the feedback that someone received from their own voice, by speaking into a microphone, taping the voice, and delaying the feedback, they would elicit stuttering and that this stuttering occurred when the delay reached a specific threshold. Tomatis duplicated this experiment by using a long tube, making holes that corresponded to a one tenth of a second delay. Lee and Black had found that articulation difficulties occurred between one-tenth and two-tenth of a second. Tomatis found very similar results. He postulated that poor lateralization in contrast with good lateralization, introduces an element of delay caused by an extra step in the transfer of information

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