Types of Hearing Loss

Conductive Hearing Loss Conductive hearing loss occurs when sound is not conducted efficiently through the outer and middle ears, including the ear canal, eardrum, and the tiny bones, or ossicles, of the middle ear. Conductive hearing loss usually involves a reduction in sound level, or the ability to hear faint sounds. This type of hearing loss can often be corrected through medicine or surgery. Sensorineural Hearing Loss Sensorineural hearing loss occurs when there is damage to the inner ear (cochlea) or to the nerve pathways from the inner ear (retrocochlear pathway of the acoustic nerve) to the brain. Sensorineural hearing loss not only involves a reduction in sound level, or ability to hear faint sounds, but also affects speech understanding or ability to hear clearly.

Central Auditory Processing Disorders A central auditory processing disorder (CAPD) occurs when auditory centers of the brain are affected by injury, disease, tumor, heredity or unknown causes. CAPD does not necessarily involve (although it may) hearing loss. Central auditory processing involves sound localization and lateralization, auditory discrimination, auditory pattern recognition, the temporal aspects of sounds, and the ability to deal with degraded and competing acoustic signals. Therefore, a deficiency in one or more of the above listed behaviors may constitute a central auditory processing disorder. CAPD is often associated with Attention Deficit Disorder (ADD) or Attention Deficit Hyperactivity Disorder (ADHD). Preventing Noise-Induced Hearing Loss Noise-induced hearing loss can result from a single loud noise such as a firecracker or gunshot. Hearing loss can also result from prolonged exposure to noise over a period of time. It occurs gradually and painlessly. The best way to prevent noise-induced hearing loss is to take care of your hearing by protecting your ears from loud sounds. We should not be exposed to 90 decibels (dB) of sound for longer than eight hours a day. For every 5 dB increase in volume, the maximum recommended exposure time is cut in half. Here are some examples of sound represented in decibels:

As you can see, there are many everyday sounds that can cause noise-induced hearing loss. Here are some simple things you can do to protect your hearing:

• Wear earplugs when you're exposed to loud noise at work or play.
• Pay attention to the noises around you. Turn down the volume on radios, TVs and stereos when you can. Whenever possible, leave noisy environments.
• Alternate a noisy activity with a quiet one to give your ears a rest.

Hearing Aid Information

Hearing aid technology can be divided into two general categories: analog and digital. In very simple terms, analog and digital refer to how the hearing aid's amplifier processes sound. Both of these categories can be further divided into more specific subcategories: Analog hearing aids: Analog hearing aids amplify the continuous sound wave by simply making it larger. There are two subcategories of analog hearing instruments: conventional and programmable. Conventional and programmable hearing aids differ in the amount and degree of adjustments the hearing aid dispenser can perform on the hearing device. A programmable hearing device allows the dispenser to adjust the amplifier more precisely to match your hearing loss. Programmable analog hearing aids, when compared to their conventional equivalent, provide greater fitting flexibility. This means that the dispenser can more readily change the way a programmable analog hearing aid operates through the use of an office computer. Sometimes the added flexibility of a programmable hearing aid is an important feature. Digital hearing aids: Digital hearing aids take the continuous sound wave and break it up into very small, discrete bits of information. This is called digitizing the signal and all digital hearing aids do this. The very fact that a hearing aid is digital does not make it better than a comparable analog aid. Beyond just digitizing the sound prior to amplification, there are differences in exactly how various digital hearing aids amplify or process sound. The more sophisticated digital hearing aids are able to amplify the softest sounds of speech while at the same time subtracting out certain types of unwanted noises. Digital signal processing allows hearing aid designers to write computer programs, called algorithms that can be customized to each individual's hearing loss. In addition, digital hearing aids enable important features -- such as dual microphones and low battery warning signals -- to be placed into a small in-the-ear device.