Sonicguide: Its Use with Public School Blind Children
Sonicguide: Its Use with Public School Blind Children
Mr. Newcomer is an orientation and mobility specialist, Program for the Visually Impaired, Bucks County Intermediate Unit, Colonial-Northampton Intermediate Unit, Doylestown, Pennsylvania.
Abstract: Use of the Sonicguide as part of an orientation and mobility program helped an elementary school student to develop and reinforce mobility concepts and spatial awareness. Several high school students successfully used the Sonicguide as an object detector and environmental sensor. Crucial questions about using the Sonicguide with children, including logistical difficulties and selection of suitable students, are raised, and some tentative answers provided.
Adult blind persons have been using the Sonicguide and its predecessors for several years. Various articles have explained its basic operating principles (Mims, 1973), described years of successful use of the device (Thornton, 1975), and pointed to its particular advantages and disadvantages in adverse weather (Farmer, 1975; Welsh & Wiener, 1976). Thornton, recounting his success with the Binaural Sensory Aid, stated, "If the writer, in adult life, taking up the device, when well over the age of 50, can achieve some measure of success in this direction, how much more may well be possible for young people growing up with the aid?" This question challenges teachers of blind children as the technology becomes available. The Sonicguide children's model, which is adjustable to fit children of widely varying ages and head sizes, is now available for use in orientation and mobility programs serving school-aged children. A regional itinerant public school program to teach visually impaired children in several counties of eastern Pennsylvania has completed the first four months of Sonicguide instruction of four children, aged five to seventeen. All have previously had conventional mobility instruction, and continue those lessons. Three of the four are congenitally blind; none has a secondary impairment.
Based upon four months' experience with the Sonicguide, this article not only raises several questions, which other O & M specialists in the future will feel challenged to answer, but also attempts tentative answers to most of the questions. The crucial questions are: What can a student do with the Sonicguide that would have been impossible without it? Does the Sonicguide significantlv increase the older student's efficiency and safety while traveling? Of what value is the device to an older student as he orients himself to a new school or neighborhood? Are there positive attitudinal or motivational changes in the student's feelings about his travel skills? What concepts can be taught with the Sonicguide that cannot be as well taught with more traditional, less expensive, materials? Must a student first learn to interpret the device's rather complex sounds before he can use the device to expand his spatial awareness? How can the device be used to reinforce and expand concepts already developed.' Does frequent use of the Sonicguide place the student at a disadvantage when he must travel without it, or does the student become more keenly attuned to his environment in general? Is it fair to allow a student to master the Sonicguide over a period of years if a Sonicguide for his personal full-time use will probably always be too expensive?
To what extent does the appearance of the glasses make their use by children and adolescents unacceptable? Which children should be chosen for instruction? Are there insurmountable logistical obstacles to including the device as part of an itinerant
TASK AND POTENTIAL
Resembling a pair of glasses, the Sonicguide emits high frequency sound beyond the range of human hearing. Whenever the ultrasound reflects back from objects in or near the travel path of the child, it reenters the device and is transformed into audible signals that the child must learn to interpret. The pitch of the sound determines distance; the lower the sound, the closer the object to be encountered. No matter what object is reflecting the sound, the pitch for a given distance remains constant so that a blind child can, with training, learn to judged distances --- a skill which may be helpful. Because the Sonicguide is binaural, the position of objects to the right or left can be determined by the relative loudness in each ear. That is, an object slightly off to the right side sounds relatively louder in the right ear. An object directly in front of the child sounds equally loud in both ears if the child's head is properly aligned. Finally, the quality of the sound varies according to the surface texture and material of the object from which the ultrasound reflects. An object that absorbs or scatters sound, e.g., a person, does not have as clear and strong a sound as a glass window, which reflects to the Sonicguide nearly all of the sound that strikes it perpendicularly. A skilled child can learn to interpret differences in sound quality, and combined with his ability to interpret pitch and position, the child can become aware of a potentially limitless amount of environmental information. Most traditional mobility drills that teach blind children basic audition concepts, spatial awareness, and sound localization, depend upon the teacher's initiating sounds through special sound balls, the Portable Sound Source, or recording equipment. The Sonicguide, on the other hand, places the child in control of the direction of the sound to be emitted, and takes advantage of the sonic properties of objects in the environment, whether they be basic practice poles, telephone poles, or school bulletin boards. Potentially then, the Sonicguide encourages exploration of the child's world and teaches the child that his movements have predictable consequences that he can act upon through his interpretation of what he hears.
SENIOR HIGH SCHOOL STUDENT
The caseload of a public school itinerant mobility teacher invariably includes an older student who has nearly completed the traditional mobility sequence. The oldest Sonicguide user on the caseload, Roy, a high school junior, anticipated using the device as an object detector and environmental sensor as he eventually incorporated the device into his regular cane travel lessons. One weekly lesson of about three hours moved Roy through basic pole drills to urban travel in Philadelphia. He explains his fast progression in terms of his other mobility skills: "I've always used echolocation to a great extent. When I was young I would snap my fingers or make other sounds to tell if I was close to something." The Sonicguide greatly extends the range and quality of information he receives. When he began using the device inside his school and then outside, Roy was surprised at how many previously unknown objects are out there and of interest and help to him. He is curious and wants to know more than simply if his path is clear. In addition to safety and efficiency, the Sonicguide adds variety and pleasure to his travel.
In terms of safety and sonic landmarks, Roy has found distinct advantages. In conjunction with his cane, Roy is warned far in advance of head-high obstacles extending from buildings and poles. He avoids traffic-control boxes and protruding telephones under which a cane can pass. Tree branches hanging over the sidewalk, ladders at a diagonal to a building; poles knocked to a dangerous angle by truck traffic no longer pose dangers. Additionally, the Sonicguide has proved helpful in congested areas because Roy can avoid contacting people with his cane. Many skilled blind travelers remember the embarrassment or discomfort caused by cane contact in an unusual situation. Roy is developing the ability to thread his way along congested sidewalks and subway platforms without contacting people or walls with his cane. An added advantage is that he looks like a better traveler; he does not need to contact pillars or walls to know - their location. His travel is seldom interrupted by people who assume he needs help. In short, he is using the device as much more than an object detector; he is locating sonic landmarks which increase his ability to remain oriented even in snow, when curbs disappear. He has not yet, however, had the opportunity to use the Sonieguide during a snow-fall when the flakes might cause problems with the device.
How helpful is the Sonicguide in the noisy, potentially dangerous subway where decisions
must be made quickly? Is there a tendency for cane skills to deteriorate because attention is paid to sonic information? Roy at times boards an elevated train at the line's end, where trains wait with motors turned off on one of two tracks. Standing in line for tickets and moving through a turnstile line are easier because the student can tell when the line is moving and in which direction. Roy can judge the location of a train soon after he reaches the platform. He also quickly locates the turnstile and speed is important because people behind the student are rushing to board the next train. The train doors can be heard if the train's engine is silent; but at other stops the sound of the train interferes with detecting the door sonically. Quickly locating the vertical poles inside the subway car is easy with the device, regardless of other sounds. The poles must be grasped to maintain balance whenever the subway car lurches.
Traveling the length of the subway platform poses this problem for the traveler: He must avoid the platform edge, and vet not stray so far from it that he encounters people sitting along the wall. The Sonicguide provides information about the distance from the wall without having to shoreline the wall with the cane. Pedestrians on the platform are easily avoided; avoiding the cane is safer for them also, especially if they are elderly or physically handicapped. Stairs out of the subway and dangerous turnstiles have a recognizable sound. And when assistance is desired. The Sonicguide makes the locating of other people much easier. Practice continues or. all of these skills, but since Roy does not use the device on some lessons he can also function without it.
JUNIOR HIGH SCHOOL STUDENT
Fourteen-year-old Wally is an adventitiously blind junior high school student who is becoming oriented to a large senior high school that he will attend next year. To locate intersecting corridors, he will need to cross diagonally large open areas with central obstacles such as fountainstelephones, and display cases. Using the Sonicguide, Wally efficiently avoids the obstacles and does not need to use protective techniques. He can cross the areas as do other students; in fact, he can follow other students at a distance if he chooses. He easily locates corridors and specific rooms, and the Sonicguide differentiates between students standing at their lockers and doorway entrances. As he learns the location of steps, he will not need to use his cane inside-so reducing the frequency of collisions in a crowded public high school. Wally's reservations about the appearance of the device are offset by knowing he can avoid embarrassing collisions, look more natural as he travels, travel with more confidence, and remain better oriented.
Outside, Wally has begun exercises that teach him to locate destinations by counting trees or listening for hedges; otherwise destinations in the middle of blocks are more difficult to locate. While it would be informative for many blind students to learn about the electronic mobility aids, a student spending considerable time learning to use the Sonicguide should be reasonably certain that one will eventually be available to him for his personal use. Wally has received a grant from the Gruber Foundation in his hometown, with the help of the Northampton County Branch of the Pennsylvania Association for the Blind, to purchase a Sonicguide for his personal use. Because Wally is one of the first blind high school students to own his own device, his experiences during the coming year should be very instructive.
The student perhaps most fascinated by the sonic glasses is second grader Gerry, aged eight. Two previous years of mobility instruction included traditional pre-cane activities in body image, laterality, protective techniques, compass directions, sound localization skills, independence within his school, riding the bus to school like other students, and activities with the Portable Sound Source that taught auditory concept development.
Because of his age, the approach to Gerry's Sonicguide instruction is markedly different from the older students. While the poles are used to teach beginning drills, lessons are shorter and more oriented toward games that encompass learning activities. Two weekly lessons of about one half-hour each during the four-month period have produced these results: Gerry has mastered the distance at which he must stop to grasp an object, and he makes judgments about the relative distances of poles. (Is there any way as efficient and student-directed as the Sonicguide for teaching the concept of distance?) He has mastered the azimuthal nature of the device and can grasp a pole after he places himself in front of it. Without having to use protective techniques, he moves securely around a large room, locates poles, judges their relative positions, and passes between them, without bumping, in search of a person "hiding." Gerry discriminates the sounds of certain objects: steps, the difference between a person and a pole, the sound of a corrugated bulletin board that yields such an unusual chirping bird sound that Gerry laughs when he approaches it. He moves around poles forming differing geometric shapes, understands basic positional concepts incorporated into the games, and can differentiate parallel from perpendicular movement. In several of these drills, the Sonicguide is reinforcing previously known skills. The Sonicguide seems a unique device, however, to teach accurate 90 degree and 180 degree turns, seems excellent at encouraging head and feet alignment, and can be used in several ways to reinforce compass direction concepts. Gerry has heard landmarks such as playground equipment, and can distinguish street sign poles from telephone poles. Gerry's posture while wearing the glasses has improved because he must keep his head erect to hear the sounds clearly.
The youngest of the four students, five year-old Dana, is congenitally blind with no reported light perception. She attends public school resource room and kindergarten all day. Her Sonicguide instruction supplements the regular mobility pre-cane sequence, in which she joins her classmates. Until this year she had had limited drills with the Portable Sound Source in anticipation of the Sonicguide program. Although the J2C model Sonicguide is designed to fit small heads, it was at first too cumbersome for Dana. She enjoyed the sounds the Sonicguide provided, but the sheer weight of the glasses necessitated rather brief lessons, and her instructor carefully monitored her feelings in case she became negative about the device. All involved want the child's experience to be positive and enjoyable; children who enjoy their activities are more successful at skill development and feel better about themselves. But the glasses were cumbersome; nose pads helped, but not enough. A supportive strap across the back of the head was not helpful. Dana's father suggested looping the front of the glasses with a piece of fine shoestring to be attached to a comfortable beanie. That slight lifting of the weight of the glasses has made a marked difference, and longer lessons are possible. [Kay, Strelow, & Kay, 1977, report successful use of a headband.] Dana is becoming consistent at determining the distance at which she must stop to reach out and touch an object. She is beginning to identify the sound of certain surfaces in a game situation, and she enjoys paralleling a corridor wall, listening for the sound of upcoming water fountains and doorways. The next phase will be learning to differentiate sounds coming from the sides. And as she matures she will tackle the skills that Gerry is mastering.
Many significant logistical difficulties face the itinerant mobility teacher. Practice poles must be portable: one solution is three-foot sections of PVC (plastic) pipe mounted in a plywood base. To simulate the detection of tree branches by vertical scanning, string with paper taped its length can be suspended at adjustable heights between two of the poles.
Because the string's height is adjustable, each crossing beneath the string becomes a new exercise in judgment for the student. The practice area must be inside if weather would interrupt the program continuity, and in this case must be large enough to avoid reflections from walls instead of the practice poles. One student practices in a Marine reserve armory. The oldest student began basic drills in an extremely wide corridor at his school and tolerated (enjoyed'?) cheerleader practice interruptions. The two youngest students fortunately have had the use of school gymnasiums. After initial drills are progressing, school hallways are excellent practice areas.
The Sonicguide equipment itself has not once malfunctioned, although the fluted ear tubes proved somewhat irritating to the ears of several students. Principals, teachers, and parents are very enthusiastic about each student's use of the device, and go out of their way to be helpful in scheduling. Physics teachers showed a special interest, and the oldest student will be demonstrating the Sonicguide to his physics class.
Selection of Students .
Probably the first question to confront the itinerant mobility teacher is the selection of students. The following criteria are only tentative. Only the students with the maturity, regardless of age, to respect the equipment should be considered. A second
impairment may rule a student out of consideration, or be a reason for instruction. Normal hearing is important, although it may in the future be possible to change the output to compensate for a hearing impairment. The sharing of one device among several students rules this out at the moment. On the other hand, a blind child confined to a wheelchair
may find the Sonicguide especially useful in familiar areas. Older students nearing graduation may not have the time needed to master the device, while young students perhaps need to concentrate upon much more basic mobility tasks. Each of the four children mentioned in this article had good sound localization before beginning instruction, had already received instruction in mobility, and showed the intelligence to learn to interpret the simpler of the sounds they heard and to discuss the concepts involved. Mims has described the Sonicguide's, "Complex and ever-changing assortment of sloshings, wheeps, and rushing sounds with varying degrees of intonation and amplitude" as. "a kind of futuristic electronic music. Mobility teachers are preparing their students for the future; the time has come to see if the Sonicguide is indeed music to their ears.
Farmer, L. W. Travel in adverse weather using electronic mobility guidance devices. New Outlook for the Blind, 1975, 69, 433-439, 451.
Kay, L., Strelow, E. R., & Kay, N. Electronic spatial sensors as training aids for blind children. Journal of Visual Impairment and Blindness, 1977, 71, 174-175.
Mims. F. M. Sensory aids for blind persons. New Outlook for the Blind, 1973, 67, 407-414.
Thornton, W. Four years' use of the binaural sensory aid. New Outlook for the Blind, 1975, 69, 7-10.
Welsh, R., & Wiener, W. Travel in adverse weather conditions. Appendix to E. Hill and P. Ponder, Orientation and Mobility Techniques. New York: American Foundation for the Blind, 1976.