:: Topic Mill | Hearing Aids ::

Hearing Aids

A hearing aid is a device used to help hard-of-hearing people hear sounds better. In the past, a funnel-like amplification cone, called an “ear trumpet” or “ear horn” was used. Also sometimes used was a desk with a built-in amplifier into which a microphone and earphones could be plugged; these worked better than passive ear trumpets but were not portable.

Now, however, the most common style is a small electronic device that fits into the wearer’s ear. The first variety of this device had a rectangular battery pack connected by a thin wire, intended to be held in a pocket. Such “body aids,” though much more portable than the desk type, still suffered significant disadvantages due to sub-optimal microphone placement. Since the microphone was not near the user’s head, it was susceptible to interfering sounds such as clothing-noise. Sound input was also distorted if the microphone was located below the mouth of a person with whom the user was conversing.

During the mid- to late 20th century, hearing aids that were carried in pockets were replaced by a more inconspicuous sort of model in which small zinc-air batteries were placed in the inserted unit itself. Cutting-edge technology allows for hearing aids so small and stylish they can be mistaken for wireless headsets.

Types of hearing aids

Body worn aids

This was the first type of hearing aid, and thanks to developments in technology they are now rarely used. These aids consist of a case containing the components of amplification and an ear mold connected to the case by a cord. The case is about the size of a pack of cards and is worn in the pocket or on a belt. Because of their large size, body worn aids are capable of large amounts of amplification and were once used for profound hearing losses. Today, they have largely been replaced by BTEs.Behind the ear aids (BTE)

BTE aids have a small plastic case that fits behind the ear and conducts sound to the ear canal, usually through an earmold that is custom made. BTEs can be used for mild to profound hearing losses and are especially useful for children because of their durability and ability to connect to assistive listening devices such as classroom FM systems. Their colors range from very inconspicuous skin tones for adults to bright colors and optional decorations for children. Recent innovations in BTEs include miniature “invisible” BTEs with thin hair-like sound tubes (see open-fit devices below). These are often less visible than ITEs and some keep the ear canal more open so listeners may still utilise their residual natural hearing (most helpful for those with normal hearing in the lower frequencies). Ideal for high frequency losses, these miniature versions are generally used for mild to moderate hearing loss. Continue

Advertisements



    Leave a Reply

    Fill in your details below or click an icon to log in:

    WordPress.com Logo

    You are commenting using your WordPress.com account. Log Out / Change )

    Twitter picture

    You are commenting using your Twitter account. Log Out / Change )

    Facebook photo

    You are commenting using your Facebook account. Log Out / Change )

    Google+ photo

    You are commenting using your Google+ account. Log Out / Change )

    Connecting to %s



%d bloggers like this: