Teaching the Use of Hearing

by Dona Sauerburger, COMS

March, 1999 newsletter

Metropolitan Washington Orientation and Mobility Association (WOMA)

At our last WOMA meeting, we shared ideas about teaching children and adults how to maximize the use of their hearing. Later, at Dona’s request, others added their ideas on the OandM listserv.

Following is a compilation of all the suggestions and comments. These came from WOMA members Susan Adams, Colleen Calhoon, Charlene Finlay, Janet Frieswyk, Jim Keim, Trudy Payne, Dona Sauerburger, Lou Smith, Linda Starner, and Gayle White, and listserv participants Gene Borquin, Lohren Caceres, Stuart Filan, Arne Harder, Leslie Kay, Carol Inglis, Susan Shier, Jenine Stanley, and Andrea Story.

Use and Awareness of Sounds in General

o In planning a route and then subsequently checking it, make note of indoor sounds such as air vents overhead, cash registers or office machines from rooms adjoining the hallway, fountains or escalators, and outdoor sounds that are constant.

o Sounds, such as traffic and other sounds, will often be different at different times of the day and on different days of the week (such as on weekends) as well as in different conditions (such as when roads are wet, or in the fall when leaves are on the ground).

o It’s important to assess people’s hearing, both functionally and with an audiological report, so we can teach appropriate and reliable skills. Some people whose hearing seems to be normal because they understand spoken conversation may be unable to hear important environmental sounds, such as traffic sounds, that are in a frequency range that is different from the human voice. This can be revealed with a functional assessment, for example starting with asking the student to listen to and identify traffic at simple, typical intersections under good conditions. An audiologist can also provide important information, such as whether the hearing is equal in both ears. You might also request from the audiologist a “location test,” which would reveal whether students have problems locating sounds behind and in front of them, or to their left and right.

o Hearing aids, cochlear implants, and other listening devices are notorious for distorting, changing, and generally making sounds unusable for orientation and mobility tasks. Many assistive devices are designed and set to enhance the human voice for communication, not to retrieve environmental sounds. In fact, they may be intentionally blocking distal environmental input. Also, no assistive listening device can reach far into the environment (such as hearing a car 300 feet away).

o Stress, fear, depression, and other emotions can reduce the ability to hear and use sounds. Several blind people said that when they were in the depths of depression, all their senses were dulled -- sounds that they could normally hear vanished, and they were left in a fog. One woman who was newly blinded was so distracted with fear while trying to follow her guide that she noticed no change in sound between an indoor room and the street outside.

According to one neuroscientific expert, accurate processing of sensory information occurs best under relaxed states because emotions are inextricably bound to our sensory perception. Perception and processing of sensory information are adversely affected when we deal with emotions such as fear, hunger, anger, sadness, anticipation, and anxiety. Our bodies generally “tense up” under the effects of these emotions, and then the brain shuts off the use and processing of senses, so that sensory feedback is annulled or confused.

Considerations for young children:

o To teach the use of sounds to young children, use the most natural situations, surroundings, and materials that are found in the student’s world, and emphasize the concepts that are most applicable to the student. For preschool aged children, play can simulate the total sound or sensory experience with the child -- play on floors that are carpeted, hardwood, or vinyl, on grassy areas, and in the sand box. In so many ways, play is the very serious business of being a preschool kid.

o The critical difference between O&M for infants and preschoolers as well as children who are developmentally delayed and O&M for older kids and adults is the importance of working within their natural settings and experiences. Older children and adults can benefit from auditory “training” in artificial settings.

o Give the young child more information about sounds by exploring specific play environments which include places with hard wood or other firm surfaces. Much more sound and vibration is produced on hard surfaces than on carpet. When a child is going through the stages of releasing/ dropping objects, banging objects against a hard surface (which is a rudimentary cane skill), rolling balls and even later building towers, the firm surface will give the child more information through sound about what is happening beyond his or her own body.

o The child should also have a variety of experience with different sounds, and ways to make sounds, just as the sighted child is treated to a variety of visual images through play and the general surroundings. Most toys are designed for the visual aspects and offer very little variety in sound; choose toys and play objects based on the sound qualities.

o For infants and children with developmental delays, there is the “Little Room.” Designed by Dr. Lilli Nielsen, the Little Room is designed to provide the child with more information about sounds and provide more opportunities to reach and explore than the typical sighted infant’s environment. Dr. Nielsen also has instructions for making a resonance board so that sounds produced on the board last longer and make a vibration.

o The sounds in long narrow hallways can provide good directional information for the toddler who is beginning to walk. Because of the difference in sound, it may be beneficial to avoid carpets when first introducing the cane to a child.

o Young children need “labeling” -- verbal explanations of what they are experiencing. For young students, the world of sounds and their “uses” are not limited to O&M objectives -- while young students are learning about sounds, they are learning and developing “language,” a language that describes the world, that helps them make sense of it.

Weather considerations:

People who normally use hearing well to line up for street crossings and other tasks will often function very poorly when wearing hoods and hats. The new polyester fleece materials seem to be able to keep warmth with much less thickness (therefore allowing sounds through) than the natural fibers. Mary-Maureen Snook-Hill, who teaches in Canada, said that they have found that headgear made with the new polyester fleece materials does indeed keep people warm without compromising their hearing. Another suggestion is to wear headbands or “toboggan”-type hats which can be pushed back off the ear whenever needed (such as when crossing streets).

Various weather conditions can affect traffic and other sounds tremendously and change them. Lou Smith described in our last newsletter how the snow can affect the sounds. On some windy days, especially in the fall with lots of dry leaves, it’s impossible to hear cars until they are nearly upon you. It’s important for our students to recognize when they are unable to hear traffic well enough to cross safely at traffic signals and at places where there is no traffic control. For the latter situations, the Timing Method for Assessing the Detection of Vehicles can be used to give feedback to teach them to recognize when they cannot hear well enough.

Echolocation / Environmental Acoustics

It is important to distinguish between the use of the terms environmental acoustics and echolocation. These tend to get mixed up, and not many people know that there is a difference.

o Environmental acoustics relates to the multiple reflections of sound from many surfaces, creating characteristic changes in the perception of sounds. One example of environmental acoustics is the change that you can hear in your voice when you move from a carpeted, furnished living room to an empty conservatory with walls of glass and a tiled floor. Concert hall designers are experts in “environmental acoustics.”

o Echolocation relates to the reflection of sound from an object back to the source which emitted a short burst of sound (such as a cane tap, click of shoes, snap of fingers). The time delay enables distance measurement. This can be done by listening to a reflection from a wall 20 meters distant which is delayed by about 60 milliseconds. One hears the emission and the echo as separate events in time.

However when there are several reflections from other big objects at different distances, the complex sound one hears is then called “environment acoustics.” In this case, the location of each of the several surfaces is difficult and the measurement of distance is very crude.

Teaching strategies:

Start with sounds that are obvious and progress to more discrete sounds:

most easy to do:

o Place a bowl near the student’s ear (with the opening facing his ear) and have him identify which side it’s on. This is so obvious it can be used to determine whether students are able to echolocate -- if they can’t tell where the bowl is, they probably can’t learn to echolocate.

o Recognize if they’re standing near a large building vs. open space

o Identify if a room is large or tiny (closet)

o Walk along a narrow hall into a large room or vice versa and notice the change in sound

more difficult to do:

o Identify intersecting hallways

o Identify open doors in the hall

needs practice:

o Determine which side of the room is larger (how far away are the walls?)

o Determine where objects are by snapping fingers or making clicking sounds. These clicking and snapping sounds reflect well from hard surfaces such as walls and poles, which make them easier to locate by echolocation. However, with practice one can also locate objects that absorb sound, such as people and padded furniture, by noticing that sounds echo from all directions except where the sound-absorbing object is. This skill (noticing which direction sounds don’t echo from) takes more practice, but it enables people to find furniture and other people in addition to poles and walls.

Game: Arne Harder from Germany plays “The Obstacle-Location Game” where you walk along the walls of a room whose walls are bare except for a movable blackboard. You get 4 points for each wall that you walk along without touching, and 1 point for reporting where the blackboard is after walking around the perimeter. However you lose 1 point if your cane touches a wall and you lose 4 points if your body touches it.

Issues:

o What is considered socially acceptable for making sounds (clicking, clapping, stomping) to facilitate echolocation? Some students in institutional homes are discouraged by the staff from making sounds even if it means that they lose orientation and have to be guided around.

o Young children need lots of experience. They will develop echolocation naturally in the real world but may need help learning to localize.

o The constant-contact cane technique seems to provide less echolocation information than the touch cane technique. The metal gliding tips seem to provide better sound for echolocation than nylon tips. The metal gliding tips normally come with the NFB fiberglass canes but they are also available for aluminum canes (they slip onto the cane just as other tips do).

o Guide dog handlers can increase echo location by attaching to their dog’s harness or collar small bells, such as jingle bells or tiny, well-made sleigh bells. Sometimes just the noise of the tack as it moves and the clank of the dog’s tags will give enough information. Also, the traveler can note how the dog reacts to certain sounds, which the dog may hear before the person does. For example, before the person is close enough to hear the sound of a water fountain, the dog may hear it and perk up, which the person can feel through the harness.

Sound Shadow

Teaching strategies:

o While standing on a sidewalk near an object that is between you and the traffic, listen to passing cars to locate the object by noticing the sound shadow that it makes. Start with large objects like a truck or van, and progress to trees and poles.

o While walking in an area with a distant, steady source of sound, locate objects by noticing when the sound is blocked by the object as you walk past it. Again, start with large objects and advance to thinner ones.

Using Traffic Sounds for Alignment

Teaching strategies:

There is difference of opinion between instructors who feel it is more effective to verbally describe to students how the traffic should sound when they are aligned, and those who feel that it’s more effective to have the students figure it out for themselves by listening to how the traffic sounds when they are aligned.

Following are two teaching strategies using the two different principles. In both cases, the students should be standing in a place where they can get no alignment information from anything but the sound of traffic (have them stand in shade, with no slope or cracks in the surface):

Strategy #1: Explain to the students that they should listen to where the traffic is loudest, and that they should turn so that the loudest point is at their side. Provide feedback as they try it until they can do it successfully.

Strategy #2: Follow the steps below:

o Position the students in alignment with the traffic and explain that this is how the traffic should sound when they are aligned. Allow them to experience that sound as long as they feel is necessary to remember how it sounds.

o Have the students turn slightly out of alignment and listen to the difference, and then turn back to see how it compares to traffic sounds when correctly aligned. Do this until the students report that they can hear a difference. If necessary, have them turn far out of alignment until they can hear the difference, then have them try to hear more subtle differences.

o Repeat the same procedure by turning slightly out of alignment in the other direction, and listen for the difference.

o Using this strategy, the students will sometimes tell you in their own words how it sounds to them when they’re aligned and when they’re not. Each student seems to describe it differently.

Regardless of which strategy you used to help the students understand how to align, have them practice with one or both of the following:

a. Disorient the students and ask them to position themselves so that the traffic sounds the same as it did when they were aligned.

b. Position the students yourself, and then ask them to determine whether they are standing in proper alignment, or turned too far to the right or left.

If the students say it sounds like they’re straight when they are not correctly aligned, explain that they are incorrect but don’t tell them which way they are facing. Have them listen again to figure out which way they need to turn to correct it, and how much to turn.

In the beginning, especially for students who are having difficulty with this task, you can accept slight errors (explain that it isn’t perfect but is good enough for now). When they have become more skilled, you can require that they work at the alignment until they are perfectly straight. Accurate feedback is important -- if they are told that they are straight when they are slightly out of alignment, it will be more difficult for them to learn what is straight.

Explaining the concepts:

These strategies are used only to help convey important ideas conceptually, they don’t help teach people to use the traffic sounds.

o To convey what direction the traffic is moving (or how it should be moving in relation to the student), you can hold a cane horizontally (about waist-high) in the direction that you are trying to convey.

For example if the student is facing incorrectly and has trouble figuring out which way to turn to be parallel to the traffic, explain that you are positioning the cane parallel to the traffic and let her feel it. Then let her turn herself until she is parallel to the cane (and therefore parallel to the traffic). You may have to first demonstrate how the cane would feel if it were parallel to her, then hold it parallel to the traffic again and have her turn to make it parallel to her. Having students first align themselves to a line that they can touch, rather than an acoustic line, can often help them understand how to align themselves to the acoustical line of traffic sounds.

Surprisingly, some students who have difficulty figuring out which way to turn to make themselves parallel to the traffic can nevertheless position a cane parallel to the traffic correctly. This shows that they can hear the traffic and know which way it’s going, but they don’t know how to turn their body to align with it. That is when this technique is most effective because they can practice turning for alignment using the cane as a physical line, rather than using the acoustical line of traffic sounds. Once this is mastered, they usually can transfer the skill to aligning with traffic sounds.

The cane can also be helpful to explain to students why traffic that is on the street beside them could sound like it is ahead of or behind them. Hold the cane horizontally at their waist beside them and let them feel that the cane is at their side. As they move their hand along the cane, they can feel that even though the cane is beside them, it extends ahead of and behind them, just as the traffic does on the street beside them.

o The braille cell can be used to explain parallel traffic (“you’re standing on dot 3 facing dot 1; you want the traffic to go from dot 6 to 4.”)

o The following method of explaining the concept, another kinesthetic approach, was taught to several O&Mers at their university programs, but they each felt that it was ineffective. Using this method, the students point back to the traffic behind them, swing their arm down and then forward to point to where they hear the parallel traffic ahead of them.

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