Hearing Aid Blog

Hearing with our skin

December 12, 2009

Hearing with our skin

If your ears can’t hear what someone is saying what about listening with your skin?
According to a study in the journal Nature, sensations on the skin can help people understand speech.
Just like looking at someone’s lips in a noisy place, or if you have a hearing loss, feeling, can also help you hear.
“From our brain’s point of view, we can hear with our eyes,” says Bryan Gick, a professor of phonetics at the University of British Columbia in Vancouver.
“From my point of view, we’re whole-body perceiving machines,” Gick says. “We just take all of the information that comes at us in our environment and merge it into a percept of something that happened in the world.”
Where does the Integration Happen?
David Ostry, a professor of psychology at McGill University in Montreal says these days the big scientific question isn’t whether our brains routinely integrate sensory information, but how.
“It’s up for grabs where within the brain this kind of integration is happening,” he says.
One possibility is areas in the brain that process sensory information, Ostry says. But he notes it’s also possible that integration takes place in the motor cortex, which controls our muscles.
Researchers say what they learn about how other senses influence hearing could help people with hearing loss, as well as people such as commercial airline pilots, who often have to decipher speech in a noisy environment.

If your ears can’t hear what someone is saying what about listening with your skin?

According to a study in the journal Nature, sensations on the skin can help people understand speech.

Just like looking at someone’s lips to help you hear better,  feeling sounds can also help you hear.

“From our brain’s point of view, we can hear with our eyes,” says Bryan Gick, a professor of phonetics at the University of British Columbia in Vancouver.  ”We’re whole-body perceiving machines,” Gick says. “We just take all of the information that comes at us in our environment and merge it into a percept of something that happened in the world.”

Where does the Integration Happen?

There’s no question that our brains routinely integrate sensory information, but how our brains do that, is still unclear.  One possibility is that integration takes place in the motor cortex, which controls our muscles.

Researchers say what they learn about how other senses influence hearing could help people with hearing loss, as well as people such as commercial airline pilots, who often have to decipher speech in a noisy environment.

Degree of Hearing Loss Varies from Person to Person

December 9, 2009

Between the two extremes of hearing well and hearing nothing, there are many degrees of impairment. The terms used to describe the degree of hearing loss are mild, moderate, severe, and profound. Most hearing losses are mild to moderate.

Mild hearing loss:  Unable to hear soft sounds, difficulty perceiving speech in noisy environments.

Moderate hearing loss:  Unable to hear soft and moderately loud sounds, considerable difficulty in perceiving speech, particularly with background noise.

Severe hearing loss:  Speakers must raise their voice. Group conversation is possible only with considerable effort.

Profound hearing loss:  Some very loud sounds are audible but hearing conversation without a hearing instrument is impossible.

The Impact of Hearing Loss on Speech Perception

Hearing loss in the inner ear (sensorineural hearing loss) mainly affects high frequency sounds. These high-pitched sounds such as “s,” “f,” “sh,” “t” play a key role in our ability to understand speech clearly. This is why a person with this type of hearing loss will often say, “I can hear but I don’t understand what’s being said.” Hearing loss drastically reduces the ability to understand speech.

The Hearing Test

The performance of the ear is tested with a special measuring instrument, the audiometer. The object of the test is to precisely register the extent of the hearing loss. This can only be done when there is no background noise to distort the result. Since the extent of the damage may be different in each ear, they need to be tested separately. In order to do this the sound signals are transmitted via headphones. Both the perception of the sound and the understanding of speech are tested. The key observations are “when do I begin to hear the sound” and “when does the sound become unpleasantly loud.” This test is usually carried out for several frequencies (or pitches), at a range of different loudness levels. The result is presented in the form of a sound-audiogram. The audiogram is a special graphic representation of the evaluation of a person’s hearing ability. The audiogram enables us to establish the degree, type, and progression of a loss of hear. Regular checks give a clear picture of any changes in the hearing system.

What do the horizontal numbers in the audiogram mean?

The frequencies (pitches), measured in Hertz (Hz) are marked on the horizontal axis. The pitch of the sound increases from left to right. Lower numbers mean lower-pitched sounds (e.g. bass voices, drums) and high numbers correspond to higher-pitched sounds (e.g. birdsong, soprano voices).

What do the digits on the left-hand side of the audiogram mean?

The hearing loss for each frequency measured can be seen on the vertical axis. The higher the number, the louder the sounds. The level is measured in decibels (dB).  0dB indicates the softest sound normally heard by the healthy ear.  120 dB is the loudest sound usually considered tolerable by human beings.

Analog, Digitally Programmable, Digital?

Every hearing instrument has at least one microphone which picks up sound from the environment, an amplifier which transforms the signal to compensate for hearing loss and a receiver that directs the signal, which is adapted for the hearing loss, into the auditory canal. This is similar to a hi-fi system although these hearing systems are much smaller and adapted specifically to the needs of the hearing-impaired individual.  Thanks to increasingly small micro-processors, digital technology has been introduced in to the most modern hearing systems. Digital hearing instruments are programmed by a hearingcare professional via computer. Acoustic signals are transformed into a binary code at high speed and with great precision. Complex calculations provide the ultimate flexibility in providing individualized solutions to hearing loss. Additional hearing system features can be offered: e.g. various hearing programs, automatic program selection, noise cancellers, and adaptive directionality. Remote control operation is also possible.

Getting Used to Your Hearing Aids

  1. Gain experience. Begin your training program in familiar surroundings in your own home. Step-by-step you can then add to the complexity of your surroundings, although very noisy environments are to be avoided initially.
  2. Continually increase your wearing time. On the first day you should not wear your hearing instruments for more than 2-3 hours. Increase this time gradually until after a few weeks you are at the stage when you can wear your hearing instruments all day without noticing them. Remember to wear your hearing instruments at home too, so you will be able to hear the telephone ringing, the doorbell, etc.
  3. Adapt the volume to the situation. Modern hearing systems automatically select a pre-programmed, acceptable volume level when they are switched on. Many modern instruments do not need any further adjustment which is why they do not have a volume control function. If you have a volume control, don’t set the volume too high. This can result in distortion rather than improved understanding. Don’t try to understand soft voices over a great distance. Remember that people who hear well cannot do that either. As you get used to your hearing instruments you can adjust the volume controls when you need increased loudness.
  4. The hearing instrument – an extension of your body. Ideally your hearing instruments should become a natural extension of your body, similar to glasses or contact lenses. This should happen naturally as you get used to your new hearing system. Should you continue to experience discomfort, consult your audiologist.
  5. Adjust to your own voice. At first you may not recognize the sound of your own voice. It is, however, very important to hear your own voice so that you can control and correct the diction and volume of your voice properly.
  6. Living with noise. The world is a noisy place. Often people with perfect hearing are able to suppress interfering noises by concentrating on the sounds they wish to hear. If, however, you have had a hearing impairment for some time you may have lost this ability. Furthermore your hearing instruments will reintroduce you to many sounds you may have forgotten, e.g. the ticking of the clock, paper being crumpled, the clicking of heels on the floor, birdsong, children laughing, etc. Not all sounds are pleasant of course. You can also learn how to ignore unwanted sounds again. Practice concentrating on what you want to hear. If you have multi-program instruments, practice choosing the best program for the situation.
  7. Taking part in discussions. Even people with good hearing have problems understanding speech if several people speak at once. It will help if you move closer to the person you want to hear and concentrate on him/her. With practice you will achieve excellent results in this type of situation.
  8. Visiting public places. Theatres, places of worship, conferences rooms and other public places present a challenge for the hearing instrument user. It is helpful to sit where the acoustic conditions are best. Normally this is not too close to the speaker but so that you can see his/her face. Many public buildings have technical installations to make it easier to hear. A telephone call prior to the visit will clarify what is available.
  9. Listening to radio and television. Concentrate on trying to follow the overall meaning rather than each individual word.
  10. Two ears are better than one. The use of two hearing instruments for people with a hearing loss in both ears has many advantages. It offers a new dimension in hearing – after all, it is not by chance that nature gave us two ears. The benefits of hearing with both ears: More natural hearing because our auditory system is designed to receive sound input from two ears. Improved ability to determine the direction from which sound is coming – e.g. knowing which way to look when you hear a truck approaching. Greater ability to hear and understand in noisy environments. Richer, smoother sound quality. Easier, more relaxed listening. Less volume required for each ear.

Practical Advice for Communicating with Hearing Instrument Users

  1. Speak clearly and naturally. It is not necessary to shout. Loud speech may overload the hearing instrument causing voice distortion and even discomfort to the wearer. Maintain a normal tone of voice, speak clearly and slowly.
  2. Move closer. Reducing the distance between the speaker and listener is helpful and encourages improved speech understanding. This is particularly important if there is background noise.
  3. Face the listener. Position yourself so that the listener can see your face and lips. Lip reading is instinctive to all of us, but it is particularly important for those with impaired hearing to supplement the sound of the speech.
  4. Attract the listener’s attention. This can be done by either using the person’s name, entering their field of vision or tapping them lightly on the shoulder.
  5. Take the surroundings into account. Avoid trying to have conversations from one room to another or in rooms with distracting noise, e.g. washing machine, vacuum cleaner, loud music, etc.
  6. Be aware of performance constraints. Never put the hearing impaired listener and their instruments under too much pressure. They both have their limits.
  7. Understand that using hearing instruments can be tiring. When conversing with a novice hearing instrument user be sensitive to signs of fatigue. Don’t force or prolong conversations if the listener is tired.
  8. Be patient. Respect the speed of progress and encourage the person with impaired hearing when obvious progress is made. Be a good listener and help the person to achieve the goal of participating in life again.

Hearing Aids and Cell Phones

November 6, 2009

Provided by the U.S. Food and Drug Administration

What is that buzzing noise in my cell phone?

People who wear hearing aids or have implanted hearing devices may experience some difficulties when trying to use cell phones. That buzzing noise you hear is interference due to radiofrequency (RF) emissions from your phone. RF interference does not occur for all combinations of digital wireless telephones and hearing aids. However, when interference does occur, the buzzing sound can make understanding speech difficult, communication over cell phones annoying, and, in the worst case, render the cell phone unusable for the hearing aid user.

Fortunately, the compatibility of cell phones and hearing aids is improving. Some cell phones have lower radiofrequency emissions or use different technologies that can reduce the unwanted effects on hearing aids.

What should I look for in a cell phone?

Rules set by the Federal Communications Commission (FCC) make it easier for you to choose a cell phone right for you. The FCC requires cell phone manufacturers to test and rate their wireless handsets’ hearing aid compatibility using the American National Standards Institute (ANSI) C63.19 standard. These ratings give an indication of the likelihood that a cell phone may interfere with hearing aids; the higher the rating, the less likely the cell phone-hearing aid combination will experience undesired interference.

Labeling on the outside packaging of cell phones will tell you if they are hearing aid compatible (HAC). Hearing aid users should read and understand these ratings when choosing a cell phone.

What do these ratings mean?

Cell phones that are rated “good” or “excellent” for use with hearing aids set in microphone (M) mode will have a rating of M3 or M4. The higher the “M” rating, the less likely you will experience interference when the hearing aid is set in the microphone mode while using the cell phone.

Cell phones are also rated with hearing aids or cochlear implants that have a T-coil. Those rated “good” or “excellent” for use with hearing aids set in T-coil mode will have a rating of T3 or T4. The higher the “T” rating, the less likely you will experience interference when the hearing aid is set in the T-coil mode while using the cell phone.

Hearing aid manufacturers use a similar rating system. The hearing aid ratings and the cell phone ratings can be combined to help identify combinations that will provide you with a positive experience. So, a hearing aid rated M2 and a wireless device rated M3 with a combined rating of 5 and would likely provide “normal” use. A ratings combination of 6 would likely provide “excellent performance”. Every individual’s hearing aid technology and settings are unique; therefore, these ratings do not guarantee performance.

Because these HAC ratings do not guarantee performance, you should “try before you buy” any wireless device if possible. You should try different brands and models to see which phone works best for you. Also, be sure to closely examine the return policy for the device and the service provider’s policy on early termination of contracts before signing up for service.

Expectations from a hearing aid

October 10, 2009

HEARING AIDS CAN:

1.  Make soft sounds louder, thus making them easier to hear.

2.  Allow you to hear in some situations that used to give you trouble, such as conversations.

3.  Help you hear high-pitch sounds better, thus helping you to understand speech better.

4. Help you feel more at ease in social situations by making it easier to hear what is being said.

HEARING AIDS CANNOT:

1.  Allow you to hear extremely soft sounds.

2.  Cure distortion in your hearing.  Distortion is usually due to a problem in your inner ear.  A hearing aid will mechanically equalize the sounds you hear, but not correct the damaged inner ear.

3.  Allow you to hear well in ALL situations of background noise.  An advanced hearing aid noise setting will enhance speech and reduce background noise; however noise will likely continue to be the most difficult listening environment.  Lip-reading will compliment the sounds you hear in all situations.

4.  Amplify only what you want to hear.

How to cope with difficult listening situations

• Ask speakers to speak in a good light and while facing the listener so that speech-reading skills can be used.
• Ask the speaker to speak clearly and naturally but not to shout or exaggerate their articulation.
• If you do not understand what a speaker is saying, ask the speaker to repeat or rephrase the statement.
• If entering a group in the middle of a conversation, ask one person to sum up the gist of the conversation.
• If someone is speaking at a distance, that person should be asked to stand closer.
• If the speaker turns his head away, ask him or her to face you to permit optimal speech-reading and listening.
• If you are attempting to understand speech in the presence of noise, try to move yourself and the speaker away from the source of the noise.
• When in a communication situation requiring exact information, such as asking directions or obtaining schedules for a trip, request that the speaker write the crucial information.
• If the speaker is talking while eating, smoking, or chewing, request that he or she not do so because of the difficulties speech-reading.
• A person who has a unilateral loss should be sure to keep his or her better ear facing the speaker at all times.
• If possible, avoid rooms with poor acoustics.  If meetings are held in such rooms, request that they be transferred to other rooms with less reverberation.
• If a speaker at a meeting cannot be heard, request that he use a microphone.
• Come early to meetings so that you can sit close to the speaker.  Avoid taking a seat near a wall to minimize the possibility of reverberation.  This is particularly important for those who use hearing aids.
• If you are going to a movie or to a theatre, read the reviews in advance to familiarize yourself with the plot.
• In an extremely noisy situation, limit conversation to before the noise has started or after it has subsided.
  • Ask speakers to speak in a good light and while facing the listener so that speech-reading skills can be used.
  • Ask the speaker to speak clearly and naturally but not to shout or exaggerate their articulation.
  • If you do not understand what a speaker is saying, ask the speaker to repeat or rephrase the statement.
  • If entering a group in the middle of a conversation, ask one person to sum up the gist of the conversation.
  • If someone is speaking at a distance, that person should be asked to stand closer.
  • If the speaker turns his head away, ask him or her to face you to permit optimal speech-reading and listening.
  • If you are attempting to understand speech in the presence of noise, try to move yourself and the speaker away from the source of the noise.
  • When in a communication situation requiring exact information, such as asking directions or obtaining schedules for a trip, request that the speaker write the crucial information.
  • If the speaker is talking while eating, smoking, or chewing, request that he or she not do so because of the difficulties speech-reading.
  • A person who has a unilateral loss should be sure to keep his or her better ear facing the speaker at all times.
  • If possible, avoid rooms with poor acoustics.  If meetings are held in such rooms, request that they be transferred to other rooms with less reverberation.
  • If a speaker at a meeting cannot be heard, request that he use a microphone.
  • Come early to meetings so that you can sit close to the speaker.  Avoid taking a seat near a wall to minimize the possibility of reverberation.  This is particularly important for those who use hearing aids.
  • If you are going to a movie or to a theatre, read the reviews in advance to familiarize yourself with the plot.
  • In an extremely noisy situation, limit conversation to before the noise has started or after it has subsided.