Hearing Aids: A Comprehensive Guide to Styles & Technology

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.

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.

How do hearing aids work?

Hearing aids use the same basic parts to carry sounds from the environment into your ear and make them louder. Most hearing aids are digital, and all are powered with a traditional hearing aid battery or a rechargeable battery.

Small microphones collect sounds from the environment. A computer chip with an amplifier converts the incoming sound into digital code. It analyzes and adjusts the sound based on your hearing loss, listening needs, and the level of the sounds around you. The amplified signals are then converted back into sound waves and delivered to your ears through speakers, sometimes called receivers.

Styles of Hearing Aids

There are three main styles of hearing aids. The styles differ by size, their placement on or inside the ear, and the degree to which they amplify sound.

Behind-the-ear (BTE)

Behind-the-ear (BTE) hearing aids consist of a hard plastic case worn behind the ear and connected to a plastic earmold that fits inside the outer ear. The electronic parts are held in the case behind the ear. Sound travels from the hearing aid through the earmold and into the ear. BTE aids are used by people of all ages for mild to profound hearing loss.

In-the-ear (ITE)

In-the-ear (ITE) hearing aids fit completely inside the outer ear and are used for mild to severe hearing loss. The case holding the electronic components is made of hard plastic. Some ITE aids may have certain added features installed, such as a telecoil. A telecoil is a small magnetic coil that allows users to receive sound through the circuitry of the hearing aid, rather than through its microphone. This makes it easier to hear conversations over the telephone.

Canal Aids

Canal aids fit into the ear canal and are available in two styles. The in-the-canal (ITC) hearing aid is made to fit the size and shape of a person’s ear canal. A completely-in-canal (CIC) hearing aid is nearly hidden in the ear canal. Both types are used for mild to moderately severe hearing loss.

"Digital circuitry gives an audiologist more flexibility in adjusting the aid to a user’s needs and to certain listening environments."

Analog vs. Digital Hearing Aids

Analog aids convert sound waves into electrical signals, which are amplified. Analog/adjustable hearing aids are custom built to meet the needs of each user. The aid is programmed by the manufacturer according to the specifications recommended by your audiologist.

Digital aids convert sound waves into numerical codes, similar to the binary code of a computer, before amplifying them. Because the code also includes information about a sound’s pitch or loudness, the aid can be specially programmed to amplify some frequencies more than others. Digital circuitry gives an audiologist more flexibility in adjusting the aid to a user’s needs and to certain listening environments.

Adjusting to Your Hearing Aid

Hearing aids take time and patience to use successfully. Wearing your aids regularly will help you adjust to them. Become familiar with your hearing aid’s features. With your audiologist present, practice putting in and taking out the aid, cleaning it, identifying right and left aids, and replacing the batteries.

• My hearing aid feels uncomfortable: Some individuals may find a hearing aid to be slightly uncomfortable at first. Ask your audiologist how long you should wear your hearing aid while you are adjusting to it.
• My voice sounds too loud: The “plugged-up” sensation that causes a hearing aid user’s voice to sound louder inside the head is called the occlusion effect. Most individuals get used to this effect over time.
• I hear background noise: A hearing aid does not completely separate the sounds you want to hear from the ones you do not want to hear. Sometimes, however, the hearing aid may need to be adjusted.