With mammals and humans, listening is classified under communication. In principle, the hearing process is as follows: sound waves are intercepted by the ear canals and directed towards the eardrum. The eardrum with the periotic bone (composed of three bones) is part of the air-filled middle ear. These three bones transfer pressure waves to the inner ear through a small membrane. The salty liquid in the snail-shaped inner ear that makes 2.5 turns contains hair cells. The pressure wave passes through the inner ear and bounces on to the hair cells. The hair cell responds to this wave with an electric discharge that is transmitted to the brain through the auditory nerve. In the middle ear, there are two middle ear muscles (already mentioned before): the tensor tympani muscle and the stapedius muscle. The middle ear is a kind of lever mechanism, which increases the sound pressure level approximately thirty times. It is regulated by these 6 two muscles. When they tense, especially the stapedius muscle, they protect the inner ear and hair cells from excessive volume, mostly from deeper tones (called the stapedius or acoustic reflex). The tensor tympani muscle sensitizes the sound conduction by tautening the eardrum.
In the classical view of ear, nose and throat medicine, the regulation of these muscles is mostly the result of a reflex, like if you put your hand on a hot stove and it withdraws reflexively, even before you realize that the stove was hot. According to Tomatis, muscles are also significantly influenced by emotional processes [1, 12]. If our emotions in the brain say “I want to hear this voice because it sounds so melodious and warm”, the middle ear muscles unconsciously contract. The frequency components of the human voice lie in the middle and higher tonal range. Tensing the middle ear muscles and eardrum amplifies and transmits these medium and high tones to the inner ear. The voice stands out amongst deeper ambient noise. (This explains our capacity to hear (when our hearing ability is normal) the voice of our interlocutor despite a wild babble of voices. Our stomach and brain say “yes” to the other person’s voice and our middle ear muscles tense correctly.)
Stephen Porges explicitly assigns the function of the middle ear muscles in this connection. They are part of the SES. Together with the ventral branch, they always tense when our brain feels that we are in a state of security and well-being. Related to the child’s development, this means that the tensing of our middle ear muscles is most likely associated with an experience of secure attachment. In this sense, Caruso’s voice touches us not only because of its richness and exceptional timbre, but also because our ANS assigns it to a state of comforting safety and ebullient joy, qualities of the ventral branch.
In the systemic listening therapy, based on Dr. Tomatis’ research, we conduct special hearing tests, a special type of audiogram. In these hearing tests, the sensitivity of a person’s hearing is determined for a variety of tones. If the hearing test shows a special emphasis on the medium and high tones described above, it is a sign of a good voice command as well as good interpersonal skills and a secure attachment. During the listening therapy adapted to their hearing tests, clients listen to Mozart’s music through special headphones. The music is altered by a sound converter. A fundamental principle of the listening therapy is that the socalled “noise gate” generates a sort of “musical micro-gymnastics” for the middle ear muscles. Thus, the emphasis of the music is constantly either on low frequencies or on high frequencies. The emphasis on low frequencies is relaxing for the middle ear muscles. When the eardrum is somewhat relaxed, deep tones are better perceived. Patients usually react to this change by relaxing deeply. The music then switches again, which stimulates the tautening of the middle ear muscles. High notes are better transmitted; the patients typically become more alert.
Based on the Polyvagal Theory, it can be assumed that the noise gate generates a pulsating activation, especially of the ventral branch. The noise gate’s emphasis on low frequencies thus activates the ventral, social branch. The emphasis on low frequencies stimulates the “good” dorsal nucleus, which mediates a sense of security and “loving peace”. This statement is very important because many other recent studies indicate that an activation of the vagus, in particular the ventral branch, enhances an attitude of attentiveness and meditation. The “musical micro-gymnastics” of the noise gate is so much more than just a muscular training. It acts on the ANS and can lead to an experience of peace, letting go and well-being. This can be used, very successfully so, with patients experiencing a burnout, anxiety, depression or tinnitus, precisely on the physical aspects of these disorders. For example: the heart’s “reins”, too tight during a depression, that can be relaxed through the listening therapy. If these reins are loosened again and recover an individual rhythm of activity and rest, then force, timbre and joy can reenter a tense or fragile voice. By finding oneself again, it is also possible to find others.
1 Tomatis A.A.: L’oreille et la vie. Itinéraire d’une recherche sur l’audition, la langue et la communication. Paris, Robert Laffon, 1977. (English: The Ear and the Voice. Scarecrow Press, 2004.)
2 Dieroff H.G.: Lärmschwerhörigkeit. (Noise-induced hearing loss) Jena, Gustav Fischer, 1994, p 46.
3 Porges S: Die Polyvagal-Theorie: Neurophysiologische Grundlagen der Therapie. (The Polyvagal Theory: Neurophysiological Foundations of Therapy) Paderborn, Junfermann Verlag, 2010.
4 Sympathetic nervous system. http://en.wikipedia.org/wiki/Sympathetic_nervous_system
5 Cannon W.B.: The mechanism of emotional disturbance of bodily functions. The New England Journal of Medicine 1928;198:877-884.
6 Darwin C.R.: The Expression of the Emotions in Man and Animals. London, John Murray, 1872.
7 Schnack G.: Der Grosse Ruhe-Nerv. 7 Sofort-Hilfen gegen Stress und Burnout. (The calming parasympathetic nervous system. 7 immediate tips against stress and burnout.) Freiburg i.Br., Kreuz, 2012.
8 Bauer J.: Das Gedächtnis des Körpers. Wie Beziehungen und Lebensstile unsere Gene steuern. (Body memory. How relationships and lifestyles control our genes.) München, Piper, 2008.
9 Kreuzer P.M., Vielsmeier V., Langguth B.: Chronic tinnitus: an interdisciplinary challenge. Dtsch Arztebl Int. 2013;110(16):278–284.
10 Levine P.A.: Waking the Tiger: Healing Trauma. Berkeley, CA, North Atlantic Books, 1997.
11 Jackson J.H.: Evolution and dissolution of the nervous system; in Taylor J (ed): Selected Writings of John Hughlings Jackson, vol 2. New York, Basic Books, 1958, pp 45–75.
12 Tomatis A.A.: La nuit utérine. Paris, Editions Stock, 1981.