Introduction: Course objectives

Audiology Practice

How the Ear Works

Hearing Loss

Detecting and Diagnosing Hearing Loss in Children

Intervention for Children with Permanent HL


Early Intervention

Communication Choices

Case studies


Credits and Acknowledgements


Last updated: 10-sep-10


Hearing Aids
Cochlear Implant
FM System

Hearing Aids

Hearing AidA hearing aid is a device that fits in or behind the ear and makes sounds louder. Hearing aids can be adjusted to increase desired sounds in a particular range depending on the particular hearing loss. The goal is to amplify sounds common in speech while keeping environmental sounds at a comfortable level. Hearing aids, however, are just that -- an aid to hearing. They do not restore hearing or correct the hearing loss; rather they amplify and shape incoming sounds to make them more accessible to the wearer. For many children, amplification can provide benefit and access to sounds. Even very young infants can be fit with hearing aids. Consistent and early use of auditory information is essential for spoken language and speech growth. Hearing aids may provide benefit for children with all degrees of hearing loss. The goal is to maximize the hearing that a child does have. There are many different brands and styles of hearing aids available for different types of hearing loss. Typically, young children are fit with behind-the-ear (BTE) hearing aids. This style of hearing aid sits behind the ear and is attached to a personal earmold which sits in the ear.

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Cochlear Implants

Boy with cochlear implantsA cochlear implant is a sensory aid or device for adults and children with severe to profound hearing loss who get only limited benefit from hearing aids. Cochlear implants work by changing sound waves into electrical signals that can be processed by the brain. Cochlear implant systems include external parts, those worn on the outside of the body, and internal parts, those that are surgically implanted into the inner ear. The internal components include a receiver/ stimulator anchored to the temporal bone and an electrode array that is surgically placed inside the cochlea (inner ear). The external components may include a behind the ear microphone, a speech processor, and a transmitter coil worn on the scalp behind the ear. The external microphone of the cochlear implant picks up sound and changes it into electrical signals that are then converted into specially coded electrical signals by the speech processor. The transmitter coil then sends the coded signal to the internal electrodes in the cochlea, which stimulate the auditory nerve and send the signals to the brain.

Cochlear implant surgery is conducted at a specially designated hospital by a specially trained otologist. The surgery to place the internal components is generally done on an outpatient basis. Three to four weeks after the surgery the external components are programmed and the cochlear implant is stimulated. Not every child is a candidate for the cochlear implant. A team of professionals will conduct a series of formal evaluations to determine if a child meets the criteria for cochlear implantation. Age, type and degree of hearing loss, and potential to benefit from conventional hearing aids are some of the things considered.

Similar to hearing aids, a cochlear implant is not a cure for deafness. Aural habilitation is necessary for children to obtain optimal performance with a cochlear implant. Children with cochlear implants demonstrate a wide range of performance based on many factors.

Follow this link for more specific information about cochlear implants:

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FM Systems

FM Systems

Children who use hearing aids or cochlear implants often have difficulty hearing speech in the presence of background noise or when the speaker is at a distance greater than three feet away. FM systems are commonly used in academic settings or in auditoriums or other large group settings. They allow children to hear the speaker’s voice better over a distance and in background noise. An FM system consists of a microphone connected to a transmitter, worn by the speaker (e.g. a teacher or parent), and a receiver worn by the child. As with other assistive devices, there has been significant improvement in these devices in recent years. Current transmitters can be as small as the size of pagers and receivers can be built into behind-the-ear hearing aids, or can be attachments that snap onto the bottom of behind-the-ear hearing aids. The microphone picks up the voice of the speaker and sends the signal to the transmitter. The signal is then sent by wireless FM sound transmission to the child’s receiver. A soundfield FM system consists of a microphone/transmitter worn by a person talking (i.e. teacher) and a receiver worn by the listener. The receiver is housed within or connected to loudspeakers that are placed throughout a room. These systems are typically used in classrooms.

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Center on Human Development and Disability, UW LEND, University of Washington,
Box 357920, Seattle, WA 98195-7920