Hearing Aids Types

If you think you might have hearing loss and could benefit from a hearing aid, visit your physician, who may refer you to an otolaryngologist or audiologist. An otolaryngologist is a physician who specializes in ear, nose, and throat disorders and will investigate the cause of the hearing loss. An audiologist is a hearing health professional who identifies and measures hearing loss and will perform a hearing test to assess the type and degree of loss.

Source: National Institute on Deafness and Other Communication Disorders, National Institutes of Health

Hearing aids are primarily useful in improving the hearing and speech comprehension of people who have hearing loss that results from damage to the small sensory cells in the inner ear, called hair cells. This type of hearing loss is called sensorineural hearing loss. The damage can occur as a result of disease, aging, or injury from noise or certain medicines.

A hearing aid magnifies sound vibrations entering the ear. Surviving hair cells detect the larger vibrations and convert them into neural signals that are passed along to the brain. The greater the damage to a person’s hair cells, the more severe the hearing loss, and the greater the hearing aid amplification needed to make up the difference. However, there are practical limits to the amount of amplification a hearing aid can provide. In addition, if the inner ear is too damaged, even large vibrations will not be converted into neural signals. In this situation, a hearing aid would be ineffective.

Source: National Institute on Deafness and Other Communication Disorders, National Institutes of Health

A hearing aid is a small electronic device that you wear in or behind your ear. It makes some sounds louder so that a person with hearing loss can listen, communicate, and participate more fully in daily activities. A hearing aid can help people hear more in both quiet and noisy situations. However, only about one out of five people who would benefit from a hearing aid actually uses one.

A hearing aid has three basic parts: a microphone, amplifier, and speaker. The hearing aid receives sound through a microphone, which converts the sound waves to electrical signals and sends them to an amplifier. The amplifier increases the power of the signals and then sends them to the ear through a speaker.

Source: National Institute on Deafness and Other Communication Disorders
National Institutes of Health

Use of a cochlear implant requires both a surgical procedure and significant therapy to learn or relearn the sense of hearing. Not everyone performs at the same level with this device. The decision to receive an implant should involve discussions with medical specialists, including an experienced cochlear-implant surgeon. The process can be expensive. For example, a person’s health insurance may cover the expense, but not always. Some individuals may choose not to have a cochlear implant for a variety of personal reasons. Surgical implantations are almost always safe, although complications are a risk factor, just as with any kind of surgery. An additional consideration is learning to interpret the sounds created by an implant. This process takes time and practice. Speech-language pathologists and audiologists are frequently involved in this learning process. Prior to implantation, all of these factors need to be considered.

Source: National Institute on Deafness and Other Communication Disorders, National Institutes of Health

Children and adults who are deaf or severely hard-of-hearing can be fitted for cochlear implants. According to the Food and Drug Administration (FDA), at the end of 2006, more than 112,000 people worldwide had received implants. In the United States, roughly 23,000 adults and 15,500 children have received them.

Adults who have lost all or most of their hearing later in life often can benefit from cochlear implants. They learn to associate the signal provided by an implant with sounds they remember. This often provides recipients with the ability to understand speech solely by listening through the implant, without requiring any visual cues such as those provided by lipreading or sign language.

Cochlear implants, coupled with intensive postimplantation therapy, can help young children to acquire speech, language, and social skills. Most children who receive implants are between two and six years old. Early implantation provides exposure to sounds that can be helpful during the critical period when children learn speech and language skills. In 2000, the FDA lowered the age of eligibility to 12 months for one type of cochlear implant.

Source: National Institutes of Health

A cochlear implant is very different from a hearing aid. Hearing aids amplify sounds so they may be detected by damaged ears. Cochlear implants bypass damaged portions of the ear and directly stimulate the auditory nerve. Signals generated by the implant are sent by way of the auditory nerve to the brain, which recognizes the signals as sound. Hearing through a cochlear implant is different from normal hearing and takes time to learn or relearn. However, it allows many people to recognize warning signals, understand other sounds in the environment, and enjoy a conversation in person or by telephone.

Source:
National Institute on Deafness and Other Communication Disorders
National Institutes of Health

A cochlear implant is a small, complex electronic device that can help to provide a sense of sound to a person who is profoundly deaf or severely hard-of-hearing. The implant consists of an external portion that sits behind the ear and a second portion that is surgically placed under the skin (see figure). An implant has the following parts:

* A microphone, which picks up sound from the environment.
* A speech processor, which selects and arranges sounds picked up by the microphone.
* A transmitter and receiver/stimulator, which receive signals from the speech processor and convert them into electric impulses.
* An electrode array, which is a group of electrodes that collects the impulses from the stimulator and sends them to different regions of the auditory nerve.

An implant does not restore normal hearing. Instead, it can give a deaf person a useful representation of sounds in the environment and help him or her to understand speech.

Source: National Institute on Deafness and Other Communication Disorders
National Institutes of Health

It’s frustrating to be unable to hear well enough to enjoy talking with friends or family. Hearing disorders make it hard, but not impossible, to hear. They can often be helped. Deafness can keep you from hearing sound at all.

What causes hearing loss? Some possibilities are

* Heredity
* Diseases such as ear infections and meningitis
* Trauma
* Certain medicines
* Long-term exposure to loud noise
* Aging

There are two main types of hearing loss. One happens when your inner ear or auditory nerve is damaged. This type is permanent. The other kind happens when sound waves cannot reach your inner ear. Earwax build-up, fluid or a punctured eardrum can cause it. Untreated, hearing problems can get worse. If you have trouble hearing, you can get help. Possible treatments include hearing aids, special training, certain medicines and surgery.

Source: National Institute on Deafness and Other Communication Disorders

A cochlear implant is a small electronic device that the surgeon places under the skin and behind the ear. The device picks up sounds, changes them to electrical signals, and sends them past the non-working part of the inner ear and on to the brain.

A cochlear implant does not restore or create normal hearing. Instead, it can help people who are deaf or who have a severe hearing loss be more aware of their surroundings and understand speech, sometimes well enough to use the telephone.

But learning to interpret sounds from the implant takes time and practice. A speech-language pathologist and audiologist can help you with this part of the process.

Researchers are studying the causes of hearing loss as well as new treatments. For example, they are studying ways to improve hearing aids so that wearers can hear sounds more clearly with little background noise.

They are also studying how to improve cochlear implants to enhance a person’s ability to understand sounds. And they are conducting a study on twins ages 50 and over to determine the extent to which age-related hearing loss runs in families.

Source: U.S. Department of Health and Human Services

Your doctor can recommend strategies to help reduce the effects of a hearing loss. Scientists are studying ways to develop new, more effective methods to treat and prevent hearing loss.

Many people who have a hearing loss wear a hearing aid. A hearing aid is an electronic, battery-operated device that makes sounds louder to the wearer. Unfortunately, only 20 percent of people who could benefit from a hearing aid actually wear one.

Hearing aids come in many shapes, sizes, and styles. Some hearing aids fit inside the outer ear or the ear canal, while others fit behind the ear.

Hearing aids can be analog or digital. Some analog aids are custom-built to meet a person’s hearing needs. More advanced analog models can be adjusted with a computer to suit a number of environments, such as a room with a lot of background noise.

Digital hearing aids use a computer chip to process sounds, and are the most flexible in adjusting to different environments. They are also the most expensive.

An audiologist can help you determine if a hearing aid, or even two hearing aids, is the right treatment for you. Wearing two hearing aids may help balance sounds, improve your understanding of words in noisy situations, and make it easier to locate the source of sounds.

Other devices also can help you hear in certain listening environments. TV listening systems help you enjoy television or radio without being bothered by other sounds around you. Some hearing aids can be plugged directly into TVs, stereos, microphones, and personal FM systems to help you hear better.

Some telephones work with certain hearing aids to make sounds louder and remove background noise. And some auditoriums, movie theaters, and other public places are equipped with special sound systems that send sounds directly to your ears.

Alerts such as doorbells, smoke detectors, and alarm clocks can give you a signal that you can see or a vibration that you can feel. For example, a flashing light can let you know someone is at the door or on the phone.

If your hearing loss is severe and of a certain type, your doctor may suggest that you talk to an otolaryngologist — a surgeon who specializes in ear, nose, and throat diseases — about a cochlear implant.

Source: U.S. Department of Health and Human Services