Page 42 - Fall2021

WHY WAS YOUR HEARING TESTED?
loss. If a child was found to have a hearing deficit, provi- sion was made for the child to be positioned within the classroom so as to optimize his/her ability to hear what transpired. The child would also be seen by a competent medical person for care. This semiquantitative technique was only occasionally adopted during the next 45 years but was used for a time in Boston and New York City schools.
The need to identify the hearing-impaired school child was recognized in the United Kingdom in a report of the Chief Medical Officer to the Board of Education (1910) of London, UK The report noted that 3-8% of all the elementary school children in England and Wales had some form of defec- tive hearing, noted the need for the testing of children, and stated that there was a lack of precise and consistent means to accomplish this. The report used a variety of different tests and felt that the best was the use of whispered speech for which there was no control of amplitude or content and consequently varied within and between tests.
Medical
During the first half the nineteenth century, children had their hearing assessed by asking them to listen to speech or the ticking of a watch. This was carried out primar- ily when the physician thought there could be occlusion of the external auditory canal by cerumen (ear wax) or foreign bodies or exudate (fluid) in the middle ear and then to determine the amount of hearing remaining in children who were considered “deaf and dumb” (Toynbee, 1860). The hearing assessment for occlusion of the exter- nal auditory canal was used to document the success of the intervention, that is, removal of the wax. One study of 411 children examined at the Deaf and Dumb Asylum found that three-fifths did not hear any sound, whereas the remaining children heard certain sounds such as repeating short words or the clapping of hands.
Tuning forks became part of the diagnostic pediatric arma- mentarium in the 1870s to differentiate between hearing loss from a conductive defect in the transmission of sound to the inner ear and a sensory hearing defect in the trans- duction of sound by the inner ear to the central nervous system. The knowledge of various tests for conductive and sensory hearing loss was well-known and extensively uti- lized by the beginning of the twentieth century.
Using tuning forks testing for children was challenging. Politzer (1902a) developed a very simple instrument called
the acoumeter (Figure 3) that allowed for diagnosing a qualitative type of hearing loss as conductive or sensory loss and allowed for differentiation of diseases of the external or middle ear and, to a much lesser extent, of sen- sorineural loss. The testing allowed for the application of the then known effective medical or surgical interventions.
Figure 3. A: Politzer acoumeter consisted of a horizontal steel cylinder (c) 28 mm long and 4.5 mm thick, connected with a perpendicular vulcanite column (h, f) by means of a tight screw. A percussion hammer (k, d) is attached above the place of attachment of the steel cylinder. This is movable on its long axis and produces the tone by falling on the steel cylinder. The device is rotated, h, so that the circular piece, i, is placed perpendicularly on the head and k, d is dropped against c which creates a sound that can be heard through air and bone conduction (Politzer et al., 1903). From the author’s collection. B: application of the Politzer acoumeter in a subject (Winslow, 1882).
42 Acoustics Today • Fall 2021