Dr. Ross on Hearing Loss
Home-based Auditory and Speechreading Training
by Mark Ross, Ph.D.
The profession of audiology has its roots in the aural rehabilitation (A/R) programs organized by the US military during WW II. Their purpose was to respond to the needs of servicemen who lost hearing as a result of war service. The medical authorities brought together a number of specialists and asked them to create an optimal A/R program. With little financial restrictions and full access to personnel and available technology, these professionals were able to create what they considered to be an ideal program. I have always considered it as a kind of mythological Camelot, one that could never realistically be emulated now. It consisted of two full months of informational classes, speechreading and auditory training lessons, ongoing hearing aid selection procedures and so on. I went through the program myself (a bit later, in January l952) and I've always been grateful for the experience
In those days, the practice of audiology was practically synonymous with A/R (then basically defined as only speechreading and auditory training). Things have changed since that time. As the profession developed immediately after the war, fewer and fewer audiologists conducted ongoing therapy with clients. At the present time, the main thrust of practicing audiologists is the administration of sophisticated behavioral and electrophysiological auditory diagnostic procedures and the selection and dispensing of hearing aids. While both are crucial functions, and the latter an absolutely a necessary aural rehabilitation step, for most people with hearing loss it is nevertheless an insufficient response to the problems caused by a hearing loss. Often, a hearing aid alone is not enough. Some people require more extensive and intensive A/R services.
There are several reasons why current generation audiologists have not gotten more personally involved in A/R, specifically its speechreading and auditory training components. One such reason can be attributed to the scarcity of objective evidence proving the value of these services. There is anecdotal evidence to be sure, but not many carefully controlled studies that demonstrate the long-term effectiveness of a training program. Without unassailable proof of this nature, skeptical audiologists are unlikely to include speechreading and auditory training activities as part of their professional activities. Insofar as speechreading lessons are concerned, while just about all of us who have provided this training devotedly believe in its value, a personal belief is not equivalent to objective evidence. The scientifically oriented clinician requires objective evidence of effectiveness to rationalize their activities.
The situation with auditory training is different, as the potential value of this therapy has a firmer theoretical and practical ground to stand on. We know that people with long-standing hearing losses often do improve their speech perception skills after being fit with a hearing aid, apparently as a consequence of prolonged experience in listening and learning to interpret the amplified speech signals. We see this most dramatically with people who have received cochlear implants; some have shown dramatic gains in speech perception performance after a year or two of implant use. If these gains are seen naturally, then it opens the possibility of further progress occurring via an intensive and dedicated training program. Current evidence suggests that such a training program can and does improve speech perception performance.
Developing information in neuroscience adds a level of theoretical support for an intensive auditory training program. It is now known that even with adults it is possible to induce structural and physiological changes in the central auditory system with enriched sensory stimulation, that is with training. It seems that an old dog can indeed learn new tricks! We know that we cannot alter hearing sensitivity at the periphery by training; the audibility of signals will not change. Rather, the goal is to increase a person's effectiveness in utilizing the sounds that are audible. There is evidence that this indeed does occur. In other words, while pure-tone thresholds will not improve as a result of training, hopefully speech perception skills can and will.
However, even if audiologists wanted to conduct intensive training, it is not a practical option because of the time and costs involved. Under current Medicare regulations, speech pathologists but not audiologists can receive reimbursement for conducting a limited A/R program (speechreading and auditory training and other communication related therapies) with their clients. The authority for speech pathologists to engage in this practice does come with a number of restrictions, such as recertification by a physician every 30 days, a combined limit of $1500 for both speech pathologists and physical therapists, and other restrictions imposed by the Medicare fiscal intermediaries. The fact that audiologists are not approved by Medicare is perhaps now the primary reason why many more of them are not personally engaged in A/R (beyond dispensing hearing aids and some commensurate counseling). Audiologists do have to make a living, and while the average cost of hearing aids is very high, it is still not sufficient to recompense an audiologist for personally conducting ongoing and time-consuming speechreading and auditory training sessions. (For convenience here, I have separated speechreading and auditory training; in the real world, an audio-visual approach would and should be emphasized).
There is a way to provide this training without the cost being prohibitively high. And that is to take advantage of the computer and internet revolution. In the past few years, a number of computer aided training programs have been developed that are designed for people to work on in their homes. These include programs on speech reading and auditory training, separately and in combination, and communication repair strategies. The major cost of such a computer-aided program would involve mainly that of the CD disk(s) which, while not insignificant, would be much less than frequent personal appointments with a clinician. However, professional monitoring and oversight is desirable and this factor would add somewhat to the cost equation.
An effective training program, of any kind, should be based on the known and accepted principles in learning theory. We know that certain conditions can optimize the transmission and retention of information. These would include frequent, perhaps smaller training increments rather than fewer large time blocs, the active participation of the subject in the learning process rather than passive listening, varied practice material to ensure a challenge but also some degree of success, and immediate feedback regarding errors. All of these apply with a home-based computer aided training program. Equally important is the fact that is the learner who is in charge of the program and is the one who takes personal responsibility for his or her own welfare in his or her own home. And not insignificantly, "therapy" can be conducted at one's convenience. No need to travel to a distant center for one's therapy sessions.
A number of such programs are available, all of which, while differing in the details, cover similar ground. The first two described below focus on auditory training (with a number of communication "tips" interspersed throughout), the third includes both auditory training and speechreading exercises, blended as desired, while the fourth also includes some of these elements, it also presents exercises in conversational strategies. All focus on areas of communication of particular difficulty to at least some people with hearing loss.
LACE (Listening and Communication Enhancement)
This program was conceived of by Dr. Robert Sweetow of the University of California, San Francisco and is described in several recent publications.
LACE includes a variety of listening tasks that are supplemented by occasional "helpful hints" conveying general A/R advice or information on communication interactions. The program requires training some 30 minutes a day, five days a week, for four weeks for completion. The listening tasks include:
Speech in Babble. This training module consists of sentences in the presence of multi-talker babble, organized into specific topics (health issues, money matters, etc.). At the beginning of the module, the sentences are presented at a level clearly audible above the background sounds. The listener is required to repeat as much of the sentence as possible silently or out loud. The next screen presents the sentence visually. If the sentence was understand (indicated through "yes" and "no" buttons on the screen), then the next sentence presentation is made more difficult to hear. If the sentence was not understood, the correct answer is displayed and played again, after which the listening task is made easier. As the training modules progress, the trainee is presented with increasing levels of listening difficulty, in this and for the other tasks as well. The intention is to increase the trainee's listening skills under adverse conditions, but at the same time ensure that some successful identification is also possible.
Time Compressed Speech. This is intended to replicate rapid speech. This proceeds in the same manner as the preceding activity, except what is modified here is the degree of time compression. The goal is to increase one's ability to understand rapid speech.
Competing Speaker. This module is similar to the speech in babble exercise, except that only a single speaker comprises the competition. The challenge here is that the primary talker can be a man, woman or child, while the competing speaker can also be one of these three voices. The trainee has to attend to just of these talkers while ignoring the competing talker (both are varied).
Target Word (or short-term memory). In this module the subject is given a target word that will appear in a forthcoming sentence. After hearing the sentence, the task of the listener is to identify the word in the sentence preceding the target word. After three successful presentations, the level of difficulty is increased. Now the target word is revealed after the sentence is presented. Prolonging the period of time between the sentence and target word increases the difficulty of the test and trains short-term memory.
Missing Word. In this task, the person hears a sentence in quiet, with one word masked completely by a random sound, such as a car horn or telephone ringing. The listener is then asked to select the correct word (including synonyms) from four choices that appear on the screen (three are possible answers and one is "none").
Research study. The developers of the program organized a multi-site study to investigate whether LACE was effective in increasing speech perceptual skills. Sixty subjects completed the study, which compared their LACE scores before and after the training program. The results of the study showed that on each of the dimensions trained in LACE (Speech in Babble, Time Compressed Speech, Competing Speaker, Target Word, and Missing Word) that performance scores improved post training compared to pre-training. The subjects were also tested on several standardized speech perception tests that required identification of sentences in noise. For these tests, also, performance improved after the training program. Based on the evidence presented, the program does appear to be effective.
More information about LACE can be obtained from www.neurotone.com. The program can only be obtained from an audiologist whose cost from the company will vary from $70 to $110, depending upon how many copies are ordered.
Sound and Beyond
Sound and Beyond was developed by the House Ear Institute and is now being marketed by the Cochlear Corporation. It is an auditory training program primarily designed for cochlear implant users (though it may also be useful for hearing aid users with severe or profound hearing losses).
The program consists of a variety of listening tasks ranging in difficulty. Assessment tests determine the level at which training commences for the eight modules. The user manual also contains a printed series of questions to aid a subject in determining the proper level to begin training. It is recommended that users monitor their progress by periodically retaking the tests. All modules provide for immediate feedback when errors are made and include a menu bar that permits a user to stop, pause the session, or to replay the last presentation. This allows the user to replay a sound as often as desired.
Pure tones. This is the most basic task in the program. Three sounds are presented in sequence while their corresponding response buttons are highlighted on the computer screen. The job of the listener is to select the tone that differs from the other two (an "odd ball" design). Correct and incorrect answers are noted. If answer is incorrect, the correct answer is highlighted on the screen and the tone is replayed. The user may repeat the correct answer as often as desired. At first, the pitch separation of the target tone is quite distinct from the other two. As the module continues, the pitch separation decreases and distinguishing the target from the other two tones becomes progressively more difficult. This task may be particularly useful for people with cochlear implants in comparing the sensations that occur when electrodes widely and narrowly spaced are stimulated.
Environmental sounds. This material is designed to train a user's ability to distinguish and then identify environmental sounds, such as a bird chirping, a car horn blaring or the ring of a telephone. The user clicks on the icon that produces the sound in question. Difficulty is increased by gradually increasing the number of choices from two to six. The most difficult level includes background noise along with the stimuli.
Male/Female Identification. This task first requires a listener to select which one of three identical words are spoken by the different gender speaker (two are the same gender and one is different). Difficulty is increased by requiring a user to identify the gender of the speaker after hearing a word spoken.
Vowel and consonant recognition. With these two modules, Sound and Beyond now moves into direct speech perception training. Both of these modules first expose listeners to differences between the speech sounds, proceeding from acoustically dissimilar phonemes to those which are similar acoustically. There are five levels in each of these modules, with the later ones requiring not just a discriminative response (same or different), but an identification of the specific vowel or consonant used (a more difficult listening task). The difficulty of the identification task increases as a user proceeds to a higher from a lower level, with the number of choices increasing from two to nine. In order to proceed to a higher level, certain performance criteria are built into each level. The listener must exceed this "bar" before proceeding to the next level. The program offers users an opportunity to experience literally thousands of vowel and consonant stimuli number in their training.
Word discrimination. In this module, the user is exposed to and given practice listening to and identifying 600 different words spoken by four different speakers (2400 tokens). The words are broken down into categories rather than acoustic similarity. As each word is spoken, the user must make his or her selection from among four choices. The words are grouped according to categories, which provide a context for the choices. Recall that every incorrect selection can be repeated as often as desired, to aid the listener form and store the correct auditory sensations.
Music appreciation. The final module helps a user hear and identify different musical instruments and melodies. A melody is played with one of four instruments shown on the screen. The user selects the proper instrument. In another task 16 familiar melodies are played and the listener selects the correct one.
Research. At least one study investigated the effectiveness of Sound and Beyond. The results indicate that the computer-based training program can be an effective tool in improve the speech perception performance of cochlear implant patients.
Sound and Beyond can be obtained through the Cochlear corporation for $295.00 (www.cochlear.com).
Seeing and Hearing Speech
This program is distributed by the Sensimetrics Corporation in Somerville, MA. It is an English version of a training program first developed in Sweden.
The program consists of four major groups: (1) vowels, (2) consonants, (3) stress, intonation and length, (4) and everyday communications. Each group is broken down into further subgroups and then subdivided further. A brief explanatory note precedes each lesson that explains the articulatory movements required during sound formation as are various communication tips.
The program permits a user to select either the visual or auditory modes, or both in combination. The stimuli can be presented with vision alone, hearing alone or in combination (the more realistic situation). Thus, a user who desires more practice in either mode separately can be accommodated. A variety of speakers are talker are used, some easier to speechread than others .The trainee can also select any one of six different types of noise at any desired loudness level to accompany the presentations. It is up to the user to select the noise and loudness level that would present a difficult, but not impossible, listening challenge. In any lesson, a practice or test condition can be selected. In the practice condition, the user selects the word, phrase, or sentence that he or she wants to see or hear.
In the test condition, the stimuli are presented in a random fashion, with the user selecting one of a number of options displayed on the screen. Information on whether the choice is right or wrong is instantly displayed. If it is wrong, the user can elect to see or hear the presentation again or just go on to the next stimuli. This continues until the lesson is completed or the user decides not to continue. Repeated trials are possible in the test mode, but the response for only the initial presentation is tabulated.
Further information about Seeing and Hearing Speech can be obtained from www.seeingspeech.com. The program is available from them and costs $85.00.
Conversation Made Easy
This program was developed by Dr. Nancy Type Murray and is now being distributed and published by the Central Institute for the Deaf in St. Louis. The entire program comes in three packages, with two designed for hearing-impaired children and the third, the one that will be reviewed below, aimed at adults and teenager with hearing loss.
This package consists of five CDs that present the three training modules. The Sounds program is contained on a single CD (the other two require 2 CDs each). There are 24 exercises in this program consisting of tasks basically requiring consonant discrimination (judging whether one differs from another) or the actual identification of consonant combinations gradually increased in difficulty. A user has the option of just listening, just looking, or both in combination.
In the Sounds program, a speaker utters some syllable and various choices appear on the screen. The listener must select the proper one (alternatives may vary from three to twelve foils). If an error is made, the stimulus is repeated and then the correct choice is identified. The listener is advised to look and listen in making choices, as some choices can be quite challenging. The exercises were designed to permit trainees to compare and contrast the sounds of speech that may look or sound alike. All the consonants in the English language are included in varying vowel contexts.
The Sentences program is designed for audiovisual training, although a user may elect to emphasize just vision or audition. One hundred and sixty primary sentences are divided into eight exercises. A similar format is used throughout. A talker recites a sentence and four pictures then appear on the screen. The subject has to select the picture that best illustrates the sentence. Note that the task is not the identification of the specific sentence itself, but rather the selection of a picture that best reflects the meaning of the sentence. For example, for the sentence "The football game is over", only one of the foils will show people departing a football game (others will be on different themes or situations). The listener is required to comprehend the gist of the message and does not need to actually comprehend all the words. The focus is on the meaning of the sentence and not on its constituent elements.
Following an incorrect response, users have five options available to help develop useful repair strategies. They can ask for the sentence to be repeated, simplified, rephrased, for just a key word, or for the sentence to be broken down into two sentences. This is a unique feature in this program. It is intended to train people to be somewhat more assertive in their communication exchanges with other people, by developing effective communication repair strategies. Each stimulus then, is accompanied by five additional utterances, any one of which can be used when the primary sentence is not understood.
In the everyday situations program, a number of video clips are presented that depict typical communication situations, such as a party, a restaurant, shopping in various types of locations, etc. At the conclusion of the brief video, a talker is shown uttering a sentence related to the situation. Four response pictures are then given, only one of which directly concerns the sentence in question. In the event an error, the subject is presented with the same five communication repair strategies that appear in the sentence identification task, but with one addition. In a number of the scenes, the talker is shown impeding communication in some manner (by holding a glass in front of one's mouth, turning away from the listener while talking, etc.). In these cases, the subject has the option of informing the talker of the actions necessary to be taken in order to foster the communication exchange (take the pen out of your mouth, look at me while you're talking, etc.). The idea, of course, is for the hearing-impaired subject to apply this and all "repair" techniques in real life.
This program (Package 1) can be obtained from the Central Institute for the Deaf in St. Louis for $200.
Each of the four programs briefly reviewed above can provide intensive communication skill practice, each with a slightly different twist. Prior to the advent of the home computer, this type of training program was simply not possible (except, maybe, in the halcyon days of the Military Service's A/R programs). It is not realistic to expect any professional to personally conduct these training exercises three to five days a week for one or more months. The expense would not only be prohibitive, but it is the rare professional who could make this kind of time commitment.
This does not mean that audiologists do not have an important role to play. Ideally, I would hope that professionals work with their clients by assisting them in the selection of the most appropriate training program (there are others as well, which were not reviewed), in helping them to get it set up, in setting personal goals, and in monitoring progress. The best kind of home-based training program should be viewed as a partnership between an audiologist and the hard of hearing person. It is a partnership that could be rewarding for both parties involved. We know that many people with hearing loss are functioning at a level below which they can operate. A home-based training program can help them improve their communication skills and thereby lessen somewhat the impact of the hearing loss on their lives.