Auditory Disabilities
Many developers don’t think about individuals who are deaf when they think of web accessibility. For too many developers, web accessibility consists of adhering to a few guidelines that ensure accessibility to screen readers for the blind. On one level, this is understandable. People who are blind will have the most trouble, since the web is a visual medium… or is it?
The web is information. That information can be presented visually or audibly. It can be presented in graphics, video, audio, animation, or in text. Our most common experience with web content is what we view through the portal of our web browser, which generally consists of text and graphics, but the web increasingly consists of video and multimedia content. Take a look at the homepage of most popular news sites and you’ll find numerous video clips.
Something to Consider About Auditory Disabilities
Many developers don’t think about individuals who are deaf when they think of web accessibility. For too many developers, web accessibility consists of adhering to a few guidelines that ensure accessibility to screen readers for the blind. On one level, this is understandable. People who are blind will have the most trouble, since the web is a visual medium… or is it?
The web is information. That information can be presented visually or audibly. It can be presented in graphics, video, audio, animation, or in text. Our most common experience with web content is what we view through the portal of our web browser, which generally consists of text and graphics, but the web increasingly consists of video and multimedia content. Take a look at the homepage of most popular news sites and you’ll find numerous video clips.
Types of Auditory Disabilities
In some ways, the content of this section is more than you need to know in order to make web content accessible to people who are deaf or hard of hearing, but it is included here in the hope that with increased understanding comes increased appreciation to such individuals, and an increased commitment to providing content that is accessible to them.
Important
The key principle of web accessibility for users with auditory disabilities is:
- Perceivable:because they cannot perceive (hear) auditory content
It should be noted that the use of the word “disabilities” in the title of this section is a controversial choice, considering the attitude of many people in the deaf community. More than any of the other groups of individuals commonly labeled as “disabled,” those who are deaf are much less inclined to think of their condition as a disability. We’ll read more about this in the last section of this article – Deaf Culture. Still, we have retained the word “disability” in this section, not to provoke controversy, but to underscore the fact that those who are deaf cannot hear audio content, and this is the critical point for web developers to remember.
Deafness is not an all-or-nothing condition. Although there are individuals who are completely deaf, there are also individuals with varying degrees of functional hearing loss. Degrees of hearing loss are often categorized as mild, moderate, severe, profound. Those who refer to themselves as deaf usually have either severe or profound hearing loss. Those with lesser degrees of hearing loss are commonly referred to as hard-of-hearing.
Degrees of Hearing Loss
Mild hearing loss:
The inability to hear sounds below about 30 decibels. Speech can be difficult to understand, especially if background noises are present.
Moderate hearing loss:
The inability to hear sounds below about 50 decibels. A hearing aid may be required.
Severe hearing loss:
The inability to hear sounds below about 80 decibels. Hearing aids are useful in some cases, but are inadequate in others. Some individuals with severe hearing loss communicate principally through sign language; others rely on lip-reading techniques.
Profound hearing loss:
The absence of the ability to hear, or the inability to hear sounds below about 95 decibels. Like those with severe hearing loss, some individuals with profound hearing loss communicate principally through sign language; others rely on lip-reading techniques.
Classifications of Hearing Loss
Conductive hearing loss:
is the result of damage or blockage of the moving parts of the ear. The bones of a healthy inner ear—the malleus (hammer), incus (anvil) and stapes (stirrup)—vibrate in response to sounds. Diseases or injury can lead to the inability of these bones to vibrate properly, preventing the proper detection of auditory information.
Neural hearing loss or nerve deafness:
occurs when the hair cells in the cochlea or the auditory nerve is damaged, thus preventing the auditory information from getting to the brain. The bones of the inner ear may vibrate correctly, but the nerves are unable to properly transmit this information for processing by the brain.
High tone hearing loss:
is, as its name implies, the loss of the ability to hear high tones. One of the most important social consequences is that women’s voices are more difficult to understand.
Low tone hearing loss:
is the inability to hear low tones. Male voices are difficult to hear and understand.
Deaf-blindness:
is the condition of being both deaf and blind. Individuals who are deaf-blind often communicate by sign language, but they must be able to feel the signs the other person is making, by essentially holding the hands of the other person while conversing. When accessing web content, they generally use refreshable Braille devices that allow them to access all of the textual content of the web page, including alternative text for images.
Causes of Hearing Loss
Most deafness occurs early in life, most often through genetic or perinatal causes. Deafness can also occur as a result of middle ear infections (otitis media), which are most common in young children. It is also possible to experience deafness later in life, though traumatic injury or diseases. Additionally, hearing loss is a common part of the aging process, especially in men.
Deafness as a Culture
Deafness is more than a medical condition. Individuals who are deaf do not simply have “diseased ears.” They belong to a community—a culture. In this sense, deafness is unique among disability types. The sense of culture is strongest among those for whom sign language is their primary language. It is this linguistic bond, perhaps more than other factors, that binds the community together. In many ways, the social character of the deaf culture can be compared to that of the African-American culture. Just as there is a strong sense of pride among African-Americans in their heritage and society, there is a sense of pride among the deaf, and they enjoy the status of cultural and linguistic minority. Deafness is much more than a physiological phenomenon. It is a way of life. In recent decades, sign language has played an increasingly central role in the cultural unification of the deaf community.
Sign Languages and “Lip Reading”
There are, however, deaf people who do not use sign language. These people have generally been raised in the oral tradition, meaning that they were taught to speak vocally, and to “read the lips” of others. This tradition was more common throughout most of the 20th century. It wasn’t until the 1970s that educators began to seriously question this approach, and to encourage the use of sign language as a primary means of communication. Sign language itself was not even recognized as a language by most people in the field, including many of the deaf who used it.
Sign language was often thought of as a system of gestures that did not fulfill the complete functionality of a true language. More recent studies have confirmed that not only does sign language have a complete syntax and grammar structure of a true language, but it also activates the same neural pathways and brain activities that all other languages do.
The result of these findings has sparked a heated controversy between the proponents of the oral tradition and the proponents of sign language immersion. Proponents of the oral tradition seek to encourage deaf individuals to be a part of mainstream society. The assumption is that deaf people will be more acceptable and accessible to people who are not deaf if the deaf can carry on “normal” conversations with them. To a certain extent this is true, but the biggest downside to this approach is that lip-reading is an inexact art of intuition and guesswork. Lip-readers are able to reliably understand about 40-60% of what others say, and must fill in the blanks for the rest of the conversation—even after years of training and practice.
When first pondering methods to make audio web content accessible to the deaf, some developers think that the best method would be to make a sign language version of the audio content. There are a couple of problems with this:
Important
- Not all deaf people understand sign language.
- Video on the web is often not large enough or clear enough to make sign language understandable.
- Not everyone speaks the same sign language.
The last point may not be one that you had considered. In the United States, for example, the most common sign language is American Sign Language, or ASL. In Britain, British Sign Language, or BSL, is the most common. In Australia, Australian Sign Language, or Auslan, is the most common. Signed English is another variation, although it is less of a full-featured language and more of a translation of spoken English into a system of signs.
When you branch out to France, Sweden, South America, and Asia, the differences are even more pronounced. Asian sign languages have almost nothing in common with American or European sign languages, and have no common linguistic root. There have been some attempts to make an international version of sign language, known as Gestuno, but this committee-developed system of signing is inferior to the world’s richer natural sign languages and has seen only limited use.
Now, the fact that there are many different sign languages around the world is not really a matter of disability access so much as it is a matter of internationalization, but the fact that there are vast differences between the sign languages of those who can read the same spoken language (e.g. English) is very much a matter of disability access. The common thread between those who speak ASL, BSL, and Auslan is not sign language, it is English—even when you take into consideration the regional differences of spelling and some vocabulary words.
Auditory Disability Solutions
The techniques for providing accessibility for users with disabilities are very straightforward – provide captions and transcripts for multimedia content (meaning video content that also has audio) and provide transcripts for audio-only content.
