How We Hear
Parts of the Ear: 
Outer Ear
   |    Middle Ear   |    Inner Ear

Hearing is one of the five senses. It is a complex process of picking up sound and attaching meaning to it. The ability to hear is critical to understanding the world around us.
The human ear is a fully developed part of our bodies at birth and responds to sounds that are very faintfaq_clip_image002 as well as sounds that are very loud. Even before birth, infants respond to sound.
So, how do we hear?
The ear can be divided into three parts leading up to the brain – the outer ear, middle ear and the inner ear.

  • The outer ear consists of the ear canal and eardrum. Sound travels down the ear canal, striking the eardrum and causing it to move or vibrate.
  • The middle ear is a space behind the eardrum that contains three small bones called ossicles. This chain of tiny bones is connected to the eardrum at one end and to an opening to the inner ear at the other end. Vibrations from the eardrum cause the ossicles to vibrate which, in turn, creates movement of the fluid in the inner ear.
  • Movement of the fluid in the inner ear, or cochlea, causes changes in tiny structures called hair cells. This movement of the hair cells sends electric signals from the inner ear up the auditory nerve (also known as the hearing nerve) to the brain.

The brain then interprets these electrical signals as sound.
Hearing Loss
Many disorders can affect the hearing of children and adults. This section provides information on the causes and effects of hearing loss in both children and adults.

What is Hearing Loss?
When describing hearing loss, we generally look at three categories: type of hearing lossdegree of hearing loss, andconfiguration of hearing loss. With children, it is especially important to diagnose and treat a hearing loss as early as possible. This limits its potential impact on learning and development. Hearing loss can greatly affect the quality of life for adults as well. Unmanaged hearing loss can have an impact on employment, education, and general well-being.
Types of Hearing Loss
Hearing Loss:  Type of Hearing Loss | Degree of Hearing Loss |Configuration of Hearing Loss
Hearing loss can be categorized by which part of the auditory system is damaged. There are three basic types of hearing loss:conductive hearing losssensorineural hearing loss, and mixed hearing loss.

Hearing Aids
An estimated 35 million children and adults in the United States have a hearing loss. For these people, selecting the most suitable hearing aids can be vital to enjoying life to its fullest. Less than 25% of all people who need hearing aids actually get them. Most people don’t realize that the majority of hearing losses can be treated with hearing aids.
Untreated hearing loss can cause embarrassment, social stress, tension, and fatigue. This is true not only for the person with the hearing loss but also for family members, friends, and colleagues. In the case of children, untreated hearing loss can affect school performance and social development. To learn more about this topic, please visit our page on the Effects of Hearing Loss on Development.
Approximately 5% to 10% of adult hearing problems are treatable medically or by surgery. The percentage is higher in children if middle ear disease, such as ear infection, is the cause. If a hearing evaluation indicates that the condition cannot be medically or surgically treated, additional testing may be done to determine whether hearing aids will be beneficial. Hearing Aids helps in

  • Helps in localizing the direction of sounds
  • Improves listening in noisy situations
  • Provides better overall hearing

Testing & diagnosis

A hearing evaluation consists o f :

Otoscopic exam An otoscopic exam is a visual check of the ears to determine the condition of the ear canal and ear drum.
Pure tone threshold testing A pure tone threshold testing is conducted in a sound-treated room with earphones or headphones.  The listener is instructed to give a response when a given tone is heard even at the faintest level.
Speech testing Speech tests may include repeating words to determine the softest level at which you can understand them, or listening to sentences to determine your most comfortable listening level.

After the hearing test is completed, your hearing healthcare professional will show you an audiogram and explain the results, including the type and degree of hearing loss and how well speech is understood in each ear.
Understanding audiograms
The results from a hearing test are plotted on a graph called an audiogram. An audiogram is arranged with the frequencies across the top. They are labeled in Hertz (Hz), with low (bass) pitches on the left and high (treble) pitches on the right. The intensity (loudness) is arranged down the left side in decibels (dB) on a scale from –10 dB to 110 dB. The further down the scale, the more intense (the louder) the signal/tone must be to be heard.

Sample audiogram

Sample audiogram

Finding a solution

Selecting hearing aids with the appropriate features will depend on many factors. A hearing healthcare professional will offer recommendations and advice to help you choose the hearing aid that is best for your hearing loss, lifestyle and budget. Remember that no hearing aid style is better than another: It is simply a matter of choosing the one that’s right for you.

Are all hearing aids the same?
Hearing aids differ in design, size, the amount of amplification, ease of handling, volume control, and availability of special features. However, they do have similar components that include the following:

  • Microphone to pick up sound
  • Amplifier circuitry to make the sound louder
  • Receiver (miniature loudspeaker) to deliver the amplified sound into the ear
  • On/off switch and batteries to power the electronic parts

Some hearing aids also have earmolds (earpieces) to direct the flow of sound into the ear and enhance sound quality. In the case of children, the earmold will need to be replaced fairly often as the ear grows.
The best hearing aid for you depends on your listening needs, type of hearing loss, and lifestyle. Your audiologist will advise you on which of the basic hearing aid styles and features best meet your needs and their related costs.

What else will I need to know about my hearing aids?
When evaluating and discussing hearing aid options with your audiologist, make sure you learn how to:

  • Obtain maintenance and repairs
  • Use special features (such as the “T” circuit, volume control, and program remote controls)
  • Determine if a hearing aid is functioning properly

Will hearing aids eliminate all my communication problems?
With hearing aids, you will hear some sounds you have not heard previously or sounds you have not heard in a long time. At first, background noise may seem loud and distracting. Your own voice may sound louder.
It can take several weeks or months to become adjusted to listening with your hearing aids. Your audiologist will provide hearing aid orientation for you as well as hearing (audiologic) rehabilitation as needed. Hearing rehab will enable you to communicate more effectively using your hearing aids.

Are there other hearing devices that will help me hear with or without my hearing aids?
Hearing aids are very helpful in one-on-one situations, but sometimes they are not enough. A hearing assistive device can help you function better in your day-to-day communication situations.
Hearing assistive devices are available for use with or without hearing aids. These devices provide extra help in specific listening situations, such as listening:

  • Over the telephone
  • With noisy backgrounds
  • In small or large group listening settings (such as restaurants, concert halls, and movie theaters)
  • At a distance from the sound source

So, even though you have a hearing aid or implant, hearing assistive devices can enhance your communication experience. Your audiologist can advise you about any assistive technologies that might be of value.