It is estimated that more than 28 million Americans are hard of hearing. For most, a hearing aid is the appropriate solution. A hearing aid is a device that helps someone who has trouble hearing. Hearing aids today are electronic instruments that receive and amplify sounds. The earliest hearing aids were usually cone-shaped devices that funneled sound towards the ear in order to amplify it. All hearing aids consist of a microphone or receiver to pick up sound waves and convert them to an electric signal. This signal is then processed and sent to a speaker, which converts it back to an audio signal. The processing serves to amplify those frequencies of which the user has trouble hearing.
There two types of hearing loss are conductive hearing loss and sensorineural hearing loss. Conductive hearing loss occurs when sound waves cannot reach the inner ear and are caused by something like a buildup of earwax, infection, fluid in the ear, or a punctured eardrum. Sensorineural hearing loss occurs when there is damage to the auditory nerve or hair cells in the inner ear. Conductive hearing loss is usually corrected by surgery. Sensorineural hearing loss is usually corrected with a hearing aid.
Hearing aids are not a perfect solution – they do have their limitations. They will not restore normal hearing, nor will they eliminate background noise. However, they may be adjusted to lessen background noise. New users to hearing aids often complain that their voices sound funny to themselves, and that they are bothered by the relative loud noise from things like refrigerator fans and traffic on the street outside. However, as they have a chance to adapt to their new hearing aid, their brain begins to filter out background noises to a more comfortable level.