Technology For Hearing Devices Part V-A

1. Technology For HearingDevices Part V-A EDUC 477/689I Devices Part V

2. Technology For Hearing • General Information on Hearing Impairments: • Between 21 and 28 million Americans are affected by a hearing impairment. • 1 out of 10 Americans have a hearing impairment. • 60% of persons over the age of 65 have a hearing impairment. • Hearing impairment is considered a hidden disability. AT 2005 Devices Part VA Davina Pruitt-Mentle

3. Technology For Hearing • Definitions: • Hard of Hearing (some degree of residual hearing). • Deafness (very little hearing; difficulty in acquiring language). AT 2005 Devices Part VA Davina Pruitt-Mentle

4. Technology For Hearing • Challenges faced by people with hearing impairment acquired before age 2: • Isolation from normal means of learning language. • Lack of linguistic frame of reference for learning to speak, write and read. AT 2005 Devices Part VA Davina Pruitt-Mentle

5. Technology For Hearing • Common problems experienced by persons with a hearing impairment: • Difficulty discriminating between background noise and the speaker. • Difficulty filtering out the reverberated sounds from the direct signal. • Difficulty with speech discrimination and a decrease in signal-to-noise ratio when the distances between the speaker and listener increases. AT 2005 Devices Part VA Davina Pruitt-Mentle

6. Technology For Hearing • Types of Assistive Technology for Persons with Hearing Impairment and Deafness • There are many ways of trying to classify the types of devices that are available to persons with hearing impairments or who are deaf. • Visit the site below to see one way to organize this large group of devices. • Assistive Communication Devices for Persons with Hearing Impairments AT 2005 Devices Part VA Davina Pruitt-Mentle

7. Technology For Hearing • Types of Assistive Technology for Persons with Hearing Impairment and Deafness • Assisted Listening Devices • Telecommunication Devices for the Deaf • Altering Devices AT 2005 Devices Part VA Davina Pruitt-Mentle

8. Technology For Hearing • Assisted Listening Devices • Any aid or device that helps the person to detect sound that he or she might otherwise miss because of their hearing impairment. • Most common assisted listening device -and the one we are most familiar with - is a hearing aid. • Other ALDs include devices that alter the frequency of telephone or doorbell alarms to accommodate a high or low frequency hearing loss and infrared, radio frequency (sound familiar?), or induction loop systems. AT 2005 Devices Part VA Davina Pruitt-Mentle

9. Technology For Hearing • Assisted Listening Devices (ALDs) - Hearing Aids • the most popular - and most commonly used - ALD. • Visit the sites below to learn about what a hearing aid is and how they work. • How Does a Hearing Aid Work? • What is a Hearing Aid? • As you review these sites, remember that hearing aids do one thing - amplify sounds. The specific amplification levels and frequencies are determined from an audiological exam. Also, each aid has advantages and disadvantages. AT 2005 Devices Part VA Davina Pruitt-Mentle

10. Technology For Hearing • Probably one of the most significant aspects of the standard hearing aid is the telecoil. • This component allows the person with a hearing aid to combine their aid with other ALDs to be most productive in a variety of settings. AT 2005 Devices Part VA Davina Pruitt-Mentle

11. Technology For Hearing • Some of the more frequently cited limitations: • hearing aids cannot always discriminate between foreground and background sounds • these devices have difficulty separating one voice from others in noisy environment • persons using hearing aids report difficulties focusing on one sound in an environment to the exclusion of others. • echos and reverberations cause specific problems for persons with hearing impairments who use hearing aids AT 2005 Devices Part VA Davina Pruitt-Mentle

12. Technology For Hearing • Limitations are compounded by the fact that persons with hearing impairments, especially acquired hearing impairments, already have foreground/background noise filtering problems and have difficulty with echoing and reverberating sounds. • Putting a hearing aid on a child is not a simple process. • Hearing aids do not solve all your problems! AT 2005 Devices Part VA Davina Pruitt-Mentle

13. Technology For Hearing • Assisted Listening Devices - Induction Loops and FM or Infrared (IR) Systems • Other ALDs increase the volume of specific sounds in the environment and allow the user of a hearing aid to focus their hearing abilities. • ALDs come in two forms: • hardwired and • wireless systems. AT 2005 Devices Part VA Davina Pruitt-Mentle

14. Technology For Hearing • Assisted Listening Devices - Induction Loops and FM or Infrared (IR) Systems • Both the hardwired and wireless systems have four basic components: • Microphone • Transmitter • Receiver • Connection to the Aid AT 2005 Devices Part VA Davina Pruitt-Mentle

15. Technology For Hearing Microphone • All ALDs have a microphone. • picks up environmental sounds and transmits them to a receiver. • The positioning of the microphone is important • You want the microphone close enough to the source of the sound (be that a voice, orchestra, radio or television set) to isolate that sound from the background noise. • Properly positioned microphones create a favorable Signal to Noise Ratio and allow the person with a hearing impairment to focus on specific sounds. AT 2005 Devices Part VA Davina Pruitt-Mentle

16. Technology For Hearing Transmitter • Transmitters receive the sounds gathered by the microphone, convert these sounds to another form of transmission (infrared light, radio waves, or electromagnetic current), and • broadcast this alternative transmission to the person. AT 2005 Devices Part VA Davina Pruitt-Mentle

17. Technology For Hearing Receiver • Accepts the broadcast from the transmitter, converts the broadcast to sound, and transmits the sound to the user. • Some receivers are worn around the person's neck; others are placed on a surface near the person. • Some receivers accept induction loops (you will learn about these soon) through a jack included in the unit. • All receivers are fairly small and light. AT 2005 Devices Part VA Davina Pruitt-Mentle

18. Technology For Hearing Connection to the Hearing Aid • connection to the hearing aid. • These connections can take one of several forms. • a headphone set that the user wears over his or her hearing aid • a direct connection (wire) between the receiver and the hearing aid • an induction loop that is worn around the user's neck AT 2005 Devices Part VA Davina Pruitt-Mentle

19. Technology For Hearing • A second distinction with ALDs is whether the system is hardwired or wireless. • Most ALDs that are commonly used today are wireless. AT 2005 Devices Part VA Davina Pruitt-Mentle

20. Technology For Hearing • Hardwired systems • Tether the individual to the amplification devices. • The person is physically connected (plugged into) the amplification system. • System will pick up sounds with their microphone and transmit these sounds to the person through a wire attached to an earphone or directly to the hearing aid. • Hardwired systems typically consist of two elements: • a direct plug-in connection between the user and the sound source - for example a TV - and • an extension microphone that attaches to the sound source • An example of a hardwired system would be a person who uses a remote microphone attached to their hearing aid to watch a television program. AT 2005 Devices Part VA Davina Pruitt-Mentle

21. Technology For Hearing Advantages of a hardwired ALD: • an alternative amplification system for the person with a hearing aid • good for providing temporary amplification (watching TV in a noisy environment) • good for one-to-one communication (the speaker can have the microphone and place it directly before their mouth, increasing the volume of the specific sound source -their voice) • portability (easy to carry and connect to a variety of device) • lower cost • easier to use that other ALDs (hardwired systems often do not require much training to operate) AT 2005 Devices Part VA Davina Pruitt-Mentle

22. Technology For Hearing • Disadvantages of a hardwired ALD: • the location and positioning of wires may be troublesome • the person using a hardwired system has limited seating options (they can only sit in certain locations to directly connect to the sound source) AT 2005 Devices Part VA Davina Pruitt-Mentle

23. Technology For Hearing • The second general type of ALD, a wireless systems • Allow the user more access to their environment because the devices are not tethered. • In a wireless system the sounds are passed from the transmitter to the receiver by either infrared light beams or through radio frequency waves. • Wireless systems come in three configurations • Induction Loop Systems • FM Systems • Infrared Systems AT 2005 Devices Part VA Davina Pruitt-Mentle

24. Technology For Hearing Induction Loop Systems • Induction loop systems are not as commonly used as the other wireless systems, but are still present in many meeting rooms (housed in walls or under the carpet) and auditoriums. • With an induction loop system the microphone picks up the sound source (speaker, television, radio, etc) and the amplifier converts the sound signals to electromagnetic waves AT 2005 Devices Part VA Davina Pruitt-Mentle

25. Technology For Hearing Induction Loop Systems • These electromagnetic waves are then broadcast through a wire (the induction loop) that is placed around the person or, in some instances, worn around the person's neck (a personal induction loop system). • The person with a hearing impairment adjusts their hearing aid to the telecoil setting to pick up the electromagnetic signals. AT 2005 Devices Part VA Davina Pruitt-Mentle

26. Technology For Hearing Induction Loop Systems • The hearing aid then converts the electromagnetic signals into sound that is amplified by the hearing aid. • Because the broadcast of an induction loop is restricted to a specific area, these devices are sometimes thought of as a semi-hardwired system because the user must remain within the enclosed broadcast area (inside the loop) AT 2005 Devices Part VA Davina Pruitt-Mentle

27. Technology For Hearing • FM Systems • A FM system (radio broadcast) uses a FCC-restricted set of radio frequency bands to broadcast sound to a person with a hearing impairment. • This system contains a transmitter and a receiver. AT 2005 Devices Part VA Davina Pruitt-Mentle

28. Technology For Hearing FM Systems • The FM system converts the sound to radio frequency waves that can be broadcast within a limited range. • The use, however, does not need to remain within a small area (as with loops) but can move freely about the room and sometimes leave the room (because radio frequency waves pass through walls). • The person wears a receiver - usually on their chest - that receives the radio waves and converts them into sound signals to be amplified by the hearing aid. AT 2005 Devices Part VA Davina Pruitt-Mentle

29. Technology For Hearing FM Systems • The user may connect to the hearing aid directly by plugging the receiver into their hearing aid, attach earphones to the receiver and place the headset over their hearing aid, connect a personal induction loop to the receiver. AT 2005 Devices Part VA Davina Pruitt-Mentle

30. Technology For Hearing • Infrared Systems • Infrared systems, the last of the three types of commonly used ALDs, work much the same as the FM system AT 2005 Devices Part VA Davina Pruitt-Mentle

31. Technology For Hearing • Infrared Systems • In an infrared device, the sound is converted to a series of infrared light beams that are broadcast throughout the environment. • Here also, the user is free to move about the room or sit where they desireas long as they are facing the broadcast unit. • Whereas FM waves can penetrate walls and intervening objects, infrared beams are blocked and the user must reestablish a direct line-of-sight with the broadcast unit. AT 2005 Devices Part VA Davina Pruitt-Mentle

32. Technology For Hearing • Infrared Systems • Because of this disadvantage most IR systems are located near the ceiling line or high on the walls of public gathering rooms. AT 2005 Devices Part VA Davina Pruitt-Mentle

33. Technology For Hearing Assisted Listening Devices • For a summary of distinct advantages and disadvantages, visit • Advantages and Disadvantages of ALDs AT 2005 Devices Part VA Davina Pruitt-Mentle

34. Technology For Hearing • Telecommunication devices • include any aid that helps the person with a hearing impairment or deafness use conventional telecommunication devices (telephones). • Telecommunication devices can include amplifiers that connect to existing handsets, special amplified handsets and, for individuals who are not able to hear or understand speech (deafness), telecommunication devices for the deaf. • Not a device per se.-Telephone relay services assist a person to use standard technology and communicate with hearing persons without the need for modified telephones on both ends of the connection. AT 2005 Devices Part VA Davina Pruitt-Mentle

35. Technology For Hearing • Alerting or Signaling Devices • alert the user to situations that they may not otherwise hear (doorbells, baby crying). • Alerting devices may produce louder sounds or alter the frequency of existing sounds, change the sound to a visual signal (flashing light), or convert the sound to a tactile signal (vibration). AT 2005 Devices Part VA Davina Pruitt-Mentle

36. Technology For Hearing • Next we will look at: • Technology for Persons with Hearing Impairment - Telecommunication & Alerting Devices AT 2005 Devices Part VA Davina Pruitt-Mentle