South Africans won’t quickly forget controversial sign-language interpreter Thamsanqa Jantjie, who shot to infamy in December 2013 when he signed gibberish during former president Nelson Mandela’s memorial service.
The plight of deaf people
Despite the negative press around the incident and questions about security at the illustrious event, one positive spinoff was the way in which it drew the attention to the plight of hearing impaired people in South Africa and the rest of the world.
Read: Stem cells may cure deafness
If given a choice about which of their five senses they could do without, most people would choose taste, smell or touch – going through life without one of these three seems less daunting than losing one’s hearing or, heaven forbid, one’s sight.
Hearing loss means that your ability to hear sound is reduced and deafness is when you are completely unable to hear any sound.
There are many causes of hearing loss and deafness; some people are born deaf and others may gradually lose their hearing during the course of their life. It is safe to say that more than half of all people experience some hearing loss after the age of 65.
There are many reasons why people lose their hearing. A few examples are ear infections, exposure to loud noise, damage to the eardrum and old age (presbycusis). Deafness can also be caused by infectious diseases like meningitis, rubella, shingles and cytomegalovirus.
Social and professional impact
Hearing loss can have a profound impact on both your social and your working life. People might think you’re ignoring them, and because you cannot take part in conversations you may become socially isolated. You may develop low social confidence, which can lead to feelings of anger and even depression. Having understanding friends and family members can however go a long way to easing the problems associated with partial or total hearing loss.
We live in a technological age and there are many gadgets designed to assist the hearing impaired like telephones and cell phones with very loud ringtones or that emit flashes of light. The same applies to alarm clocks and doorbells, and nowadays many television programmes and films have subtitles.
Since time immemorial people have found creative ways to deal with the problem of hearing loss. One only has to think of the famous “ear trumpet” that was popular before the advent of electrical devices. (Ear trumpets are large, funnel-shaped “acoustic” devices that strengthen the sound to the eardrum.)
Most hearing impaired people are able to lip read to some degree. The main problem with lip reading, though, is that you have to be able to see the face of the person you are communicating with, which limits your ability to communicate with more than one person at a time.
Read: Computer being developed to read people's lips
Sign language has also been around for a long time and is a very effective way for deaf people to communicate. People who can hear, but are unable to speak also use sign language. Sign language is not universal and most countries have their own version. An advantage of sign language is that it can be used effectively in a group situation.
Advent of hearing aids
Acoustic devices like ear trumpets offered very modest amplification, but the advent of electricity improved matters considerably. The first wearable hearing aid was developed by Aurex Corp., an electronics company in Chicago. It consisted of an earpiece connected to an amplifier-receiver, which was in turn connected to a battery pack strapped to the wearer’s leg. It was cumbersome, but it worked.
In the 1940s further innovations followed where the amplifier, batteries and microphone were combined in one unit that was much less obtrusive.
In 1964, an American hearing-aid manufacturer, Zenith Radio, released a small, light behind-the-ear device with an integrated circuit amplifier and a small 1.2-volt battery. The microphone, placed inside the ear was connected to the unit which was attached behind the ear.
Read: Hear, hear!
Behind the ear aids (BTE) can be used for mild to severe hearing loss and because the electrical components are not located inside the ear, there is less chance of damage.
Currently there are many types of hearing aids available, tailored to suit people’s individual needs.
The older types of hearing aids use an analogue system whereby sounds are picked up by a microphone and converted to electrical signals which are transmitted into the ear.
Nowadays, however, many hearing aids use digital technology, where the sound is converted to bits and manipulated before the signal is amplified. Digital hearing aids are much more flexible and adjustable. Although they are more expensive, they are so small as to be almost invisible.
As far as size is concerned there are three types of hearing aid:
- Very small models that are mounted deep inside the ear canal and cannot be seen
- Slightly larger models that fit in the ear, but are visible
- The classic behind-the-ear model
BAHA and cochlear implants
A relative new development is bone-anchored hearing aid (BAHA), based on bone conduction. This surgically implanted device is useful for patients without external ear canals where the skull is used to transmit sound to the inner ear. BAHA involves an operation and is relatively expensive.
Cochlear implants are used in the case of profoundly deaf people who gain little or no benefit from conventional hearing aids. A cochlear implant allows sounds to bypass damaged portions of the ear to directly stimulate the auditory nerve. It also requires surgery and because hearing through a cochlear implant is different from normal hearing it takes a while to learn or relearn hearing.
Read: 400th cochlear implant at Tygerberg hospital
Over the last few years great progress has been made and today’s hearing aids are so small they’re virtually invisible; they also contain a microcomputer that responds to surrounding noise, virtually eliminating feedback and echoes. These devices “filter out background noise, clean up and clarify the sound quality, automatically adjust the volume. Plus, they are computer-programmed to match the nuances of each person's hearing loss.”
Even though the latest devices attempt to “filter out background noise” this can still be a problem to many people who use hearing aids. They struggle to “tune out” background noise which drowns out the voice of the person they’re speaking to – often making social occasions in e.g. a restautant an ordeal.
Preventing hearing loss
Although most of us will experience some loss of hearing as we grow older through normal “wear and tear”, the best way to prevent hearing loss is to protect your hearing against excessive noise. Exposure to loud noise can damage the delicate hairs cells in the inner ear and lead to permanent hearing loss.
We shoud try to stay clear of sources of hazardous noise like firearms, power tools loud music and firecrackers – and professionals who are exposed to high noise levels should take care to protect their hearing. If you need to shout to be heard by someone within an arm’s length away, it could be a serious risk to your hearing. You can protect your ears by either avoiding such situations or wearing earplugs.
The following warning signs are indicators that you’ve been exposed to dangerously high levels of noise:
- You can hear people talking, but you struggle to understand what they’re saying.
- You experience a full or heavy feeling in your ears after spending time in a noisy area.
- Your ears buzz or ring after you’ve been exposed to noise.