So why does the treatment work for some children and does not work or even harm the others? As there is no definite answer to the question at present, we may suggest the following hypothesis. We know that many people with autism do suffer from auditory problems (especially, hypersensitivity to certain sounds). AIT is aimed to reduce this hypersensitivity by retraining the ear to tolerate certain frequencies and pitches. However, we always should address the causes of auditory hypersensitivity and not the symptoms per se. Very often hypersensitivity is caused not by certain frequencies or certain sounds but by the number of auditory stimuli, the rate of auditory processing the person has to cope with and even other 'non-auditory' stimuli (lights, movements, etc.) that can contribute to sensory overload and result in auditory hypersensitivity. Training the ear to tolerate certain frequencies may bring improvement in short term but as it does not address the improvement of sensory processing of other channels that may be the main source of the person's overload, it is short-lived. AIT administered to the person whose main difficulties are rooted in auditory problems (i.e. they are the causes and not the symptoms) may produce 'miraculous' results, as it happened to Georgiana Stehli. When the primary problem is addressed and eliminated (or lessened), we can see immediate improvements in other systems as well, as they do not need to compensate for impaired auditory channel any more and may 'do their own job'. On the other hand, if auditory problems result from the auditory system being just compensation for other sensory systems with primary impairments, AIT does little to 'cure' the condition.
References:
Berard, G. (1993). Hearing Equals Behavior. New Canaan, CT: Keats.
Stehli, A. (1991). Sound of a Miracle. New York: Avon Books.
Tomatis, A. (1991). The Conscious Ear. New York: Station Hill Press.
