At the Laboratory of Auditory Neurophysiology in the Johns Hopkins University School of Medicine they have been studying the effect of moderate but continuous noise on rats during the early stage of their development. They found that this distorted the rat’s tonotopic map. Crucially they found that the problem could be corrected after the rat had matured by exposing the rat to 7 kHz tones. This may point towards both a cause of some phonic dyslexia and why the Bernard Audio Integration Technique works.
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