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FEATURED ARTICLE
Why Was Your Hearing Tested: Two Centuries of Progress
Robert Ruben
Introduction
Today, almost every human being in the developed world and many in the rest of the world will have the opportu- nity to have their hearing tested from birth until old age. Testing, however, depends on interrelated factors includ- ing (1) the awareness of hearing loss; (2) the development of tools to test hearing; (3) knowledge of the causes of hearing loss; (4) the ability to intervene to restore or prevent further hearing loss; and (5) the development of devices to compensate for hearing loss.
Individuals undergo a hearing evaluation to determine whether a hearing loss is present and, if so, how great a loss; to determine the nature of the disease causing the hearing loss; and to provide a basis for determining whether there was further hearing loss due to environmental noise.
Although hearing loss has no doubt been ubiquitous in human populations, particularly with aging, testing for hearing loss and efforts to mitigate these losses are rela- tively recent. Indeed, the assessment of loss is only a few centuries old. The purpose of this article is to share some of the history of the evaluation of hearing loss, demon- strating that doing so is complex, but it has involved some of the leading “stars” among hearing researchers.
Before 1801: Qualitative and Subjective Assessments of Hearing Using the Human Voice
Anatomical and clinical writings that concerned the
ear and hearing before the beginning of the nineteenth century did not address evaluating the hearing of most individuals. There was the awareness that hearing could come through bone conduction (the conduction of sound to the inner ear through the bones of the skull) that had been known since the sixteenth century as illustrated in the frontispiece of Bulwer’s Philocophus (1648) (Figure 1).
Bone conduction was observed in patients by Du Verney (1683), who noted that some hearing-impaired people would hear much better when the end of the vibrating instrument was held in the teeth and did not depend on hearing coming through the external auditory canal. He also diagnosed the blockage/closure of the external auditory canal as an anatomical site of the hearing loss.
As late as 1801, hearing ability was assessed by the sub- jective and qualitative perceptions of the patient and the physician as noted by Cooper in evaluating the results of his surgical intervention.
“A woman about thirty-six years of age consulted me, in December last, respecting some disorder in her child. In attempting to converse with her, I found her so extremely deaf that it was with difficulty I could make her hear me... I immediately punctured the membrane of the left ear, being that in which the hear- ing was most defective. The operation was no sooner performed, than, to my great joy, and of course to hers, I found that, in that ear, she could hear what 1 said to her, without any particular exertion on my part to speak loud. She staid with me about half an hour; and, when she left me, was capable of hearing every thing that was said in the ordinary tone of conversation” (Cooper, 1801, p. 441).
1802 to 1921: Quantitative Measures of Hearing Ability Using the Human Voice and Physically Generated Sounds Children
The earliest quantitative assessment of hearing was car- ried out in deaf children to determine if therapy improved their hearing. The first was by Wolke (1802), who devel- oped an instrument to ascertain whether there was any improvement in the hearing of deaf children after they
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40 Acoustics Today • Fall 2021 | Volume 17, issue 3
https://doi.org/10.1121/AT.2021.17.3.40