Key Concepts
• Plasticity: At a time when the idea of plasticity of the brain was in its infancy, Dr. Tomatis discovered that it was possible to retrain and improve the processing of sound by the brain stem and cortex using filtered music (music with certain frequency ranges removed or enhanced) and the sudden and random alteration to the pitch or tone of the music (gating).
• Ears and Eyes: The ears and the eyes work together more than most people realize: the vestibular system in the inner ear sends signals to the neural structures that control eye movement.
• Electrical Stimulation: Sound waves entering the outer ear are transformed into electrical impulses in the inner ear and sent to the brain; those impulses provide energy to the brain and influence our ability to focus and sustain attention. For example, brain scans show that children with ADD/ADHD lack “energy” in key parts of the brain that permit attention and focus.
• Relay stations to the brain: The vestibular and cochlear systems, located in the inner ear, work together to relay sensory input to the brain. They play a key role in our ability to integrate our senses, and their successful interaction is essential for language development, sensory processing and motor function. More specifically, once sound arrives at the brain stem from the cochlea, the special center in the inner ear where sound is transduced to nerve impulses, it passes upwards toward the speech center in the cortex via a number of relay stations or nuclei. The specially treated iLs music has been designed to influence the function of ear drum and adjacent bone, as well as improve the processing that occurs at these relay stations. In turn, there is an improvement in the ability to perceive where sound is coming from, thereby making it possible to perform tasks requiring convergence of information from both ears.
• Pitch discrimination or “selectivity”: In the part of the brain known as the colliculus, processing influences the ability to recognize the relationship between high and lower tones and the integration of sound with other sensory information (vision, touch…). This ability to differentiate a higher tone from a lower tone is critical because the meaning of what we are saying is often carried by tone of voice. Those with poor selectivity have difficulty with determining whether someone is angry or joking, or they have trouble distinguishing a question for a statement. They also can’t understand the “key” words of a conversation. Selectivity is also important in helping us distinguish between letters that sound alike. People who struggle with the difference between a “p” and “b”, or a “t” and “d” are at a disadvantage in reading, spelling and writing. Listening therapy improves the ability of the inner ear to differentiate similar tones, enabling increased selectivity.