Presentation on theme: "A brief history of hearing aids and tinnitus sound enrichment devices. By James Stibbards Audiologist Aintree Tinnitus Support Group 3 rd March 2010."— Presentation transcript:
A brief history of hearing aids and tinnitus sound enrichment devices. By James Stibbards Audiologist Aintree Tinnitus Support Group 3 rd March 2010
Early days The 1 st written account of medical treatment of tinnitus is all the way back to the Egyptians. For the “Bewitched ear and humming in the ears” they would infuse oil, frankincense, tree sap, herbs and soil; and they would administer it using a reed stalk placed in the external ear.
This is Enki, the god of water. The Mesopotaminans used to chant to get rid of the whispering or singing in their ears. “Whoever thou may be, may Enki restrain me” Another incantation was “It hath flown against me. It hath attacked me. O seven heavens, seven earths, seven winds, seven fires, by heaven be ye exorcised
The Greeks and Romans Early Greco-Roman medicine defined the treatment of tinnitus based on the cause of the disease. Later, the works of Hippocrates and Aristotle really were the first to introduce the idea of masking. They were fond of saying, "Why is it that buzzing in the ear ceases if one makes a sound. Is it because a greater sound drives out the less?"
Middle ages Welsh treatment recommended to take a loaf of hot bread, divide it in two, and put it in each ear as hot as you could take it and thus perspire and by the help of God you would be cured.
The Renaissance They thought that wind would become entrapped in the ear and circle around inside it, and so they would trephinate the mastoid to allow the wind to escape.
19 th Century The French physician, Itard, is widely recognized as the father of audiology. He argued that the role of the physician was to make the tinnitus bearable. A technique that rarely failed was to cover the internal sound by an external one. The sound should be matched as far as possible to the tinnitus. For example, a roaring fire should mask a roaring tinnitus
The 20 th Century In 1903 a doctor named Spaulding used a piano to match the frequency of tinnitus. He would increase the volume of the note until the tinnitus became inaudible for his patient.
The 20 th Century In 1928, two researchers, Jones and Knudsen bombarded the auditory system with an outside sound similar to tinnitus but louder. They developed a large instrument that could be placed on a bedside table for patients experiencing difficulty sleeping. This became the very first bedside masker.
The 1 st wearable devices In 1973, Jack Vernon, Ph.D. led a research group that was the only group in the US formally studying tinnitus. One day he received a visitor, Dr. Charles Unice, who travelled from California to visit him regarding his severe tinnitus.
As they passed an outdoor fountain, Dr. Unice came to an abrupt stop. Reluctant to leave the soothing sounds of the fountain he told Dr. Vernon, “Standing right here I cannot hear my tinnitus. It’s the first time I’ve been unable to hear that unconscionably wretched sound since it began over two years ago. This is wonderful!” After several more discussions, Dr. Vernon formed the idea of using a wearable masking device as a method of providing relief from tinnitus. The rest, as they say, is history.
Wearable Sound Generators WSG may be prescribed to patients who do not have significant hearing loss. The devices are similar to hearing aids except that they do not amplify sound; they produce white noise The brain can very easily learn to ignore external sound, especially if it’s at a constant level and frequency
Desk top devices Produce a variety of environmental sounds Can be linked to a “pillow speaker” Should be switched on all day
Benefits of sound enrichment Weakens the tinnitus signal by decreasing the difference between tinnitus and the background sound The sounds should be non-intrusive, pleasant and relaxing to listen to They should not cover the tinnitus (i.e. they must not mask the tinnitus sound)
Hearing aids Hearing aids can help people with hearing loss and in many cases they also reduce tinnitus symptoms. First, tinnitus is exacerbated by silence because the brain turns up its sensitivity by seeking the neural stimulation it’s being deprived of due to hearing loss. Second, hearing aids amplify enough background noise to partially mask tinnitus sounds for many people.
The 1 st hearing aids
Concealed Hearing Devices of the 19th Century
Acoustic chairs Acoustic Chairs were a clever example of incorporating a hearing device within an everyday object Perhaps the most ingenious design of an acoustic throne was created by F. C. Rein for King John VI of Portugal
Electrical devices During the 20th century, aids for hearing evolved from mechanical to electrical devices. Using an external power source, sounds could now be made louder than was possible with earlier mechanical designs Early Electrical Hearing Aids were based on telephone technology invented by Alexander Graham Bell in the late 19th century
Acousticon Model 28, 1927 This hearing aid is typical of early electrical hearing aids. It was large and not easily transportable – the batteries were cumbersome and the carbon components were highly sensitive to heat and cold.
Hearing aid glasses
Internal workings of an analogue BTE hearing aid.
Digital hearing aids
In the ear aids Otarion ECA (ear canal aid) 1961 Oticon 1978 Oticon 1987 Bernafon ITC (in the canal) 1997
The future Who knows!
Main References Tinnitus Retraining Therapy. Jastreboff PJ, Hazell JWP. Cambridge University Press 2004 Subjective Tinnitus Jayson S. Greenberg, M.D. March 12, 1998 Baylor College of Medicine Bobby R. Alford Department of Otolaryngology-Head and Neck Surgery Tinnitus Elizabeth Willingham, M.D July 22, 2004 Baylor College of Medicine Bobby R. Alford Department of Otolaryngology-Head and Neck Surgery Tinnitus Masking by Barry Keate How Hearing Aids Work by Stephanie Watson
References cont. The History of Hearing Aids – From Seashells to Mini-computers 09/11/2008 Matt thehistoryof.net Looking at the History of Hearing Aids: The Past, Present, and Future of Hearing Aid Technology Speech-Language Pathology and Audiology at Kent State University Hearing Aid Museum Online Deafness in Disguise: Concealed Hearing Devices of the 19th and 20th Centuries Washington University School of Medicine, St. Louis, Missouri Published by the Bernard Becker Medical Library Google images