By Firasath Malkan, clinical audiologist and
student of the Master in Clinical Audiology and Hearing Therapy
Auditory training benefit is evidenced by a change in recent times. In the 19th century it was widely believed that auditory training involved in improvement in peripheral hearing. This belief has been largely supplanted in the last three decades by the opinion that improvement in “hearing” results from not only central use of available sounds, but also the interpretation of auditory input requires the use of multiple processes beyond hearing. Cognitive functions, pragmatics, language mastery, and visual perception are only a few of the components of auditory process information.
Auditory training is meant to help people with hearing loss, improve their ability to interpret, process, and assimilate auditory input.Intervention can be provided individually or in group setting. Although group settings are valuable and desired to foster socialization and improved communication strategies and behaviors, it can sometimes be difficult to meet the individual auditory training needs of the group members. For this reason, Auditory training intervention is best served on a one to onebasis with program designed with individual requirement considered. Its most common use is with children with prelingual sensorineural-impairment, especially those with moderate to profound degree of loss with congenital onset. Another targeted population for auditory training in recent times has been cochlear implant recipients, both children and adults. There is strong evidence thata structured program of listening training enhances the benefits derived from cochlear implant.
In the past it was not considered necessary to have meaning associated with auditory signal while training. The later approaches consider it necessary to have meaning associated with the auditory signals. The later techniques do not have too much of a difference between listening training and learning training. Hence traditionally auditory training has been considered important component of audiological rehabilitation process.
Goldstein (1939) introduced an approach to auditory training in the United States in the late 1890s and early 1900s. Auditory training involves a development of and/or improvement in the ability to discriminate various properties of speech and non- speech sounds (Goldstein, 1939).
The 25 year period between 1970 and 1995 was a most remarkable time in the field of Aural Rehabilitation. At one level most professional, parents, advocates, and policy makers now agree that it is a societal responsibility to provide needed early intervention programs for children with established disabilities and for those whose developments may be compromised as a result of biological and environmental factors. Aural Rehabilitation is the process of identifying and diagnosis of hearing loss, providing different types of therapies to the clients who are hard of hearing and implementing different amplification devices to aid the client’s hearing abilities.
An intervention program includes family counseling, hearing aid fitting (or cochlear implant), selection of appropriate assistive listening devices and follow up support and speech perception training. It also encompasses other aspects of child’s educational and rehabilitation program, such as speech and language therapy, educational and classroom statement and communication mode. The intervention program also includes instruction for child’s parents about how to nurture their child’s language, listening and conversational skills. To maximize communication performance, the person with hearing loss must learn to take advantage of all the sources of information available to assist in interpretation of auditory cues. To best accomplish this, they must use visual and auditory information and communication strategies and be prepared for communication failures. As such these concepts become the focus of communication therapy, most commonly referred to as auditory/visual training (Auditory training and speech reading).
Auditory training is the backbone of an oral aural educational set up. It is the very foundation on which the whole edifice of a child’s oral communication skills depends. It opens up the entire world to the child as most human beings around the child transact and communicate with spoken language. Spoken language is normally received at the brain via the auditory channel. The brain is able, stage-by-stage to develop awareness of the acoustic cues underlying linguistic distribution and thus to separate the pattern which make up language. Similarly it is through audition that the child experiments with and monitors motor speech production as development proceeds from babbling to conversation. In order to recognize and produce speech patterns the child must have adequate if not consistent exposure to oral language in a context which is meaningful to him.
The acquisition of language is further linked to auditory sense in human beings because it is a time locked function related to early maturational periods in the infant’s life. The earlier and larger the auditory language stimulation, the better and efficient will be the language and speech skills. On the contrary, if the gap between onset of hearing impairment and age of detection and age of intervention becomes larger, then the language and speech of such hearing impaired will be poorer and less efficient.
The majority of the hearing impaired is not totally deaf. Very often they have remnants of hearing i.e. residual hearing as if the gates were slightly open. Making use of it and training the child to use this residual hearing is auditory training. Auditory training is the process by which children learn to recognize and understand auditory signals available to them Jill Bader (1999).
Numerous attempts have been made to define auditory training in the past. Though similar in some aspects, these definitions vary considerably according to the orientation of the definer and special considerations dictated by factors associated hearing loss, such as its degree and time of onset.
Goldstein (1939) worked primarily with deaf children and felt that auditory training involved a developmental and/ or improvement in the ability to discriminate various properties of speech & non speech signals. These properties include loudness, pitch, rhythm and inflection.
Auditory training is a set of procedures aimed at helping the aurally handicapped become more proficient in attending to the speech sounds, discriminating one from another and effecting on increase in retention of sounds. Kelly (1953).
Probably the most commonly referred to definition of auditory training is attributed to Carhart (1960), who considered auditory training a process of teaching the child or adult with hearing impairment to take full advantage of available auditory clues. As a result, Carhart recommended an emphasis in therapy on developing an awareness of sound, gross discrimination of nonverbal stimuli and gross and fine discrimination of speech.
Auditory training constitutes a systematic procedure designed to increase the amount of information that a person’s hearing contributes to its total perception.Sanders (1971).
More recently, in discussing the use of auditory training with children, Erber (1982) described it as the creation of special communication conditions in which teachers and audiologists help hearing impaired acquire many of the auditory perception abilities that normally hearing children acquire naturally without their intervention.
Many auditory training programs, after a consideration of auditory skills level, pertain to the stimuli used in training activities. Most auditory training programs include both analytic and synthetic kinds of training activities.
2.1. Analytic training
In this thelistener attention is focused on segments of the speech signal, such as syllables or phonemes. More emphasis is placed on utilizing acoustic cues, such as the presence or absence of voicing in the words coat and goat than on gaining meaning from the speech signal. Presumably, one’s ability to recognize these segments in isolation will carry over to real-word communication tasks, allowing them to recognize connected discourse better.
2.2. Synthetic training.
During this training, individuals learn to recognize the meaning of an utterance, even if they do not recognize every sound or word. They don not perform an analysis of the signal on a sound-by-sound or syllable-by-syllable basis.
There is no clear cut dichotomy between analytic and synthetic training; rather, this is a continuum, and listening activities will gravitate from focusing attention on understanding the gist of a message. In the same lesson, a student might perform analytic training activities and then switch to synthetic activities.
The more current approaches to auditory training vary considerably. According to Blamey and Alcantara (1994), it is possible to categorize them into one of four general categories, based on the fundamental strategy stressed in the therapy: Analytic, Synthetic, Pragmatic and Eclectic.
Pragmatic training includes the listener being instructed about how to get information which will be important for communication this is done by changing the circumstances in which the interaction takes place. The most important factor in this is to develop the residual hearing skills. Factors that a listener with a hearing loss can control includes level of signal which can be adjusted between the distance of the speaker and listener,Signal to noise ratio can be increased by moving close to the speaker or moving away from noisy area to a more quieter location and context and the complexity of message can be controlled by asking questions and using appropriate repair strategies
Eclectic training includes that combines most or all of the strategies previously described.While the auditory training programs to be described all have analytic, synthetic, or pragmatic tendencies, most would best be described as eclectic, since more than one general strategy for the training of listening skills typically is used with a given child or adult.
Individual attention not the only method of dealing with the problems of the hearing handicapped. Auditory training administered in a group situation can help the Hard-of-hearing (H-O-H) achieve goals through working with others. Group training has along and learning takes place. In schools and various training institutions throughout the country, classes are becoming larger and larger as these institutions attempt to answer the demand of society to educate more and more students. Group work is not peculiar to teaching & learning situations, but has been found useful in psychotherapy.Group Auditory training has some of the characteristics of a teaching-learning classroom situation. Also, it is often similar to the group psychotherapy session.
The primary aim of auditory training is to achieve good communication skills but the long term goals ofauditory training are more far reaching and cover a broad area.
Better understanding of the spoken language of others: This includes improvement in speech perception i.e., the ability to understand speech through hearing.
More rapid development in the use of language: The rate of language development should be at a faster pace and must progress in the direction of normality.
Better speech clarity: Normal hearing children imitate the speech patterns of adults and self-correct their own speech by comparing their own speech with that of adult. This is done through hearing. Thus a goal of auditory training is that the child will listen to speech patterns of adults and learn to monitor his or her own speech.
Higher academic achievement: The first three goals facilitate the child’s success in academics.
Better social – emotional adjustment through a link with the hearing world: The child’s overall progress in the areas mentioned above result in better abilities to adjust to a world that largely consists of people with normal hearing, it also improves the psychological adjustments with the world.
3.1. Importance of Auditory Training
Because hearing loss will prevent perception of some of the acoustic cues in speech, affected children ordinarily require an increased quantity of input to attempt partially exposure to secondary but still salient acoustic ones in speech signal will permit such children to learn to take advantage of them. For most of the hearing impaired one can take no more effective measure with regard to minimizing an auditory based linguistic system than to employ a child’s innate biological capacity as the most potential. Most hearing-impaired individuals and hearing aid users’ brain receive incoming acoustics signals that are, to some degree, different, and presumably inferior, to that which the individual with normal hearing receives. Another reason is that hearing and listening are quite different and listening is a learned behavior which develops as a result of the search for meaning. Hearing requires audibility, but for a good listener, the listener must integrate a number of skills including attention, understanding, and remembering. Patients presenting similar audiometric profiles often obtain very different benefits from amplification.
3.2. Candidacy for Auditory Training
Auditory plasticity refers to the ability for change to occur in the sensory system responsible for the transmission of acoustic information. “Plasticity” is a term used to describe a variety of physiological changesin the central nervous system in response to sensory experiences.
The term Plasticity, as applied to auditory speech perception, is usually associated with the concept of critical periods. Penfield(1959) proposed the idea that the learning language was only possible up to age of 10-12. He suggested that the nervous system had a finite period of development and that certain skills could not be learned beyond a facilitating growth period. Lenneberg (1969) used the term “Critical period” to characterize speech and language development. Critical periods are most often associated with the developing nervous system. If sensory deprivation occurs one may never have access to facilitating stimuli. Another idea associated with developmental plasticity is that some type of a signal must pass through the auditory system before critical periods are activated. In words; it is possible that there could be a delay in the onset of critical periods if no activation of the auditory system has taken place.
The age at which the hearing loss was identified and intervention was provided is a critical factor. Results are better when intervention beginsat ayoung age. Research shows that children identified and fitted after the age of six months (Yoshinaga-Itano.et.al., 1998).The amount of residual hearing also determines the amount of benefit that is possible through the hearing aids and indirectly affects the outcomes of auditory training. Children who derive greater benefit from a hearing aid find it easier to attain higher levels of auditory skills because they have more access to the speech spectrum. Hence it is less common for adults to receive auditory training. Adults who receive training typically are those who experienced a recent change in hearing status. For example, someone who had just received a Cochlear Implant may receive auditory training to accelerate the learning process that often occurs during the first months following implantation. Someone who has incurred hearing loss following trauma or use of ototoxic drugs may receive training to adjust to his/her radically altered listening state. Speech through a listening device may sound different from how they remember it, and they must learn to interpret what they hear.
3.3. Factors affecting the success of Auditory training
Auditory training or any skills training involves systemized and directed practice. What a Hearing –Handicapped person learns through periods of auditory training is partly attributable to the length of time he practices and the knowledge and competence of the audiologist who has outlined and is managing the aural rehabilitation program.Success of auditory training involves factors such as:
Motivation: any progress will depend in large measure on the degree of willingness to accept auditory training as an important and worthwhile undertaking. This does not mean, however, that the highly motivated, hard-of –hearing person will show tremendous progress and one with low motivation will make no progress. They also report that hard-of –hearing show increased motivation when they are placed in competitive situations. This is one of the advantages of group therapy.
Intelligent cooperation with the clinician of those in close association with the Hearing Handicapped individual: it is of utmost importance that a realistic set of goals be outlined and understood by those who are near the person with HL, as well as by the handicapped individual. If this is accomplished and if those closest to the handicapped individual are kept informed of the aims of the program as it progresses, much good can result. Those who live with handicapped persons can provide opportunity for continued practice in the home and continued encouragement. Encouragement and understanding by others do not guarantee that the hearing-handicapped individual will maintain or increase his level of motivation, but they provide the kind of support that frequently determines whether or not an attempt at aural rehabilitation is successful. Time devoted to counseling the family of the hard-of –hearing person serves a valuable purpose.
Age of the client: Auditory training should be undertaken as soon as it is discovered that the hearing handicap cannot be reversed by medical or surgical intervention. This means that some youngsters who are one year old or even younger should receive training. At these early ages, habits of attending to sound are formed which essential to later are training involving discrimination among sounds. It is particularly important because it affects early oral language development. In other learning task the evidence indicates a decrement in accuracy and extent of learning as the individual progresses from maturity to “old” age.
Practice materials employed by the clinician: the practice materials suggested for AT are comprised of an aggregate of sounds, noises, and speech. From the standpoint of good training, practice materials should vary in many dimensions. A broad range of practice material willprovide exposure that is comparable to many situations in which the training will later be applied.
Establishment of proper habits by the clients: to ensure effective AT, the audiologists must make certain that the client develops certain habits that will increase his chances for success. Two items are particular importance: (1) the hard-of–hearing person must develop the habit of listening carefully to instructions given at the outset of each exercise and of asking for further instructions if he is not sure he has understood. (2) The hard-of-hearing person must be encouraged to check on the accuracy of his responses after each set of exercises.
Ability of the client to understand the tasks (principles involved): an important factor in learning is understanding the principles that support the task being performed. The audiologist should inform the handicapped individual, when possible, of the reasons for doing the tasks and of their underlying principles. These explanations should be simple enough to be clear and understandable to the handicapped person. An understanding of the general principles will enable the handicapped person to apply them to new tasks that have characteristics in common with the old.
Knowledge of progress: the literature on the psychology of learning generally is agreed that giving an immediate report of results to the subject after he has completed his task is of the utmost importance.
Four Design Principles: Many auditory training curricula are organized according to four design principles. These 4 design principles are followed in developing and ordering training objectives.
Auditory skill level: the first consideration in designing an auditory training curriculum pertains to the person’s hearing abilities. Results from an audiological assessment often are used to assign a student to one of four auditory skill levels (Erber, 1982).
Sound awareness, Sound discrimination, Identification, Comprehension represent a continuum of skills.
Children with significant residual hearing and adults who have had normal hearing before incurring a hearing loss may not progress through these four stages of auditory skill development in the same order. For instance, an adult CI user will be aware of the presence or absence of sound the first time the device is turned on and likely will have some speech discrimination skills. A child who has some residual hearing, or who incurred a HL gradually over time, also will demonstrate more advanced listening skills.
During the awareness phase of auditory learning, which usually will only involve infants, babies and children as most adults have sound awareness, will make a point of showing a child the source and meaning of a sound, and reinforce the child when he/she responds to sound.
Common AT activities for the second level of AT task, discrimination, might require a child to first make gross sound discrimination then move on to fine discrimination. In an AT session, the child might be asked to discriminate b/w syllables, words, phrases, and sentences that are short and long (e.g., “the car goes beepand the cow says moooo….”) or b/w words that are long or soft.
In identification task, older children might identify the respective words used and in a comprehension task, the child or adult might read a story to the patient and then ask questions about what they read.
Activity kind: Formal kinds is a training that presents highly structured activities, may involve drill; usually scheduled to occur during designated times of the day, either in a one-room lesson format or in a small group. For instance, a clinician may speak a series of words without letting the student watch. The student then repeats each word. After every successful repetition, the student drops a coin into a bowl. In this example, the speaking of a series of words represents a drill activity and the collecting of coins represents a reinforcement activity
3.4. Auditory training approaches:
3.4.1. Wedenberg’s Approach (Wedenberg 1951):
It is an early approach to auditory training, used with children with severe to profound hearing loss. It was first described by Wedenberg.
His training also served to exploit whatever residual hearing a child possesses. His approach was eventually labeled as unisensory, since he advocated that speech reading should not be consciously emphasized until the child developed a proper listening attitude.
His program was directed towards increasing the child’s attention to the sound. Both environmental and speech sounds were used in the early stages, which he referred to as“ad concham amplification”. This involved speaking directly into the child’s ear at a close range (1/2 inches) rather than the child use hearing aids.
Exercises, which helped the child become aware of and attend to sound at increasing distances, were used. These included presentation in isolation vowels and voiced consonants whose formants were thought to be within the child’s (with hearing impairment) audible range.
Syllables were used in a variety of formal therapeutic activities, as well as informal settings at home. Combining individual vowels and consonants learned in isolation resulted in perception of a limited number of words. At this time Wedenberg advocate part time use of hearing aid.
Later, training progresses to short sentences formed by words already recognized by the child acoustically. Although not given direct focus, speech reading could be used as a supplement.
His method was directed towards development of auditory, speech and language skills in children with either a congenital or prelinguistic hearing loss of severe to profound proportion.
3.4.2. Verbotonal (Peter Guberina, 1952):
A novel approach toward delivering amplified sound to HI listeners has been proposed, called the verbotonal method (Guberina, 1964).
The verbotonal method is designed to develop auditory perception and speech production through the special amplification equipment, tactual stimulation delivered by a bone conduction vibrator and body movements calculated to produce varying degrees of muscular tension associated with the production of speech sounds.
It’s effective for establishing good spoken language and listening skills. Based on a developmental model of normal hearing children.
The verbotonal method is based on the theory that amplification of the frequencies at which HI is greatest results in added distortion of the auditory signals and should be avoided.
Guberina advocates the use of a special auditory training unit (SUVAG II) composed of banks of filters that can deliver selected bands of frequencies from 20-20000 Hz.
She hypothesized that each person has an ‘optimal band of frequencies’ through which auditory information is least distorted, this frequency band usually corresponds to that frequency region in which hearing is best.
SUVAG II is adjusted to pass only the optimal field of hearing, determined for each child individually by presenting filtered and unfiltered nonsense syllables for detection or identification.
He believes that amplification of auditory cues below 500 Hz to include rhythmic patterns and sound fundamentals can help hearing impaired to perceive higher speech frequencies.
Because most SNHL is greatest in the HF, the verbotonal method stresses delivery of LF amplification, auditorily their earphones and tactually through a small vibrator held in the hand.
In addition to the auditory tactual stimulation kinesthetic movements are associated with each speech sound and used by teacher and children during speech.
In early stages of verbotonal training, nonsense syllables or single words are used exclusively as auditory stimuli.
Accurate imitation by the child, including normal vocal pitch, is the criterion for success.
The verbotonal method confines AT to perception and imitation of speech, represented by nonsense syllables, words and sentences.
Guberina advocates the verbotonal method for all ages and types of deafness, congenital or advantageous regardless of the degree of hearing loss.
3.4.3. Acupedic approach
This is a unisensory approach where the term was coined by Dr. Henkandhas been advocated by Dorin Pollack in 1952. The term ‘acu’ refers to acoustic and ‘pedi’ refers to pediatrics. This approach is not only to teach listening skills but also teaches language.
Principle: Early training using audition only, avoidance of lip reading and other cues, anduse of normal speech pattern.
Dorin Pollack has described the pre-requisites and steps to be carried out for this approach. The pre-requisites are:
– Early Identification of hearing impairment preferably by 1st
– Fitting binaural ear devices (recommended for those with profound hearing loss).
– Training through one modality, that is, auditory modality.
– Normal contact with the environment.
– Prolonged systematic training which is intensive.
This kind of training can be given to children who even have profound hearing loss according to them, children up till 5 years can be given the training but not above 7 years of age.
Pollack has mentioned the following steps to be taken in order to carry out the method:
– Awareness of sounds-initially loud sounds and later softer sounds.
– Attending to sounds.
– Responding to sounds.
– Discrimination between sounds.
– Developing feedback mechanism.
Do not use speech reading or lip-reading:
– Reason she recommends this that eye cannot detect rhythm and other suprasegmental aspects of speech.
– Eye does not provide adequate feedback about the way person produces speech himself/herself.
– People who speech read are much tensed, because the person has to strain a lot to speech read.
Proprioceptive feedback cannot replace auditory feedback. One gets feedback about position, movement etc.
– Using normal speech patterns and everything should be taught meaningfully.
– Language develops through imitation.
– Articulation is taught later on. All of these training is through individualized training program and not in group session.
Advantages of Acupedic approach:
– Children learn to use their auditory mechanism to their maximum.
– They learn vocabulary and language more easily.
– Voice quality of person is much better,
– Articulation tends to get better.
– Children who learn speech and language earlier would be able to integrate with others and then find employment later.
One of the earliest approaches in listening training which gives systematic steps was given by Carhart in 1960. It includes both childhood and adulthood procedures.
Carhart’s auditory training program for prelingually impaired children was based on his belief that since listening skills are normally learned early in life, the child possessing a serious HL at birth or soon after will not move through the normal development stages important in acquiring these skills. Likewise, when a hearing loss occurs in later childhood or in adulthood, some of the person’s auditory skills may become impaired even though they were intact prior to the onset of the hearing loss. In each instance, Carhart believed that auditory training was warranted.
Childhood Procedures: Carhart outlined 4 major steps or objectives involved in auditory training for children with prelingual deafness. They are:
– Development of awareness of sound: The child has to recognize when a sound is present and attend to it. The child should be surrounded with sounds that are related to daily activities and that are clearly audible.
– Development of gross discrimination: Initially involves demonstrating with various noisemakers that sounds differ. Training at this level involves discrimination of several parameters of sound, such as frequency, intensity (loud versus soft) durational (long versus low) properties of sound. When the child is able to recognize the presence of sound and can perceive gross difference with non-verbal stimuli, then move on to the next step of gross discrimination for speech sounds.
– Development of broad discrimination among simple speech patterns:By now the child is aware that the sound differs and is ready to apply this knowledge to the understanding of speech. Familiar meaningful phrases that is sufficiently different to minimize confusion.
– Development of finer discrimination for speech: Fine discriminations of speech stimuli in connected discourse and integrating an increased vocabulary to enable him or her to follow connected speech in a more rapid and accurate fashion.
Carhart also felt that the use of vision by the child should be encouraged in most auditory training activities.
Adult Procedures: He recommended that auditory training with adults focus on reeducating a skill diminished as a consequence of the hearing impairment.
This approach establish “an attitude of critical listening” which involves being attentive to the subtle differences among sounds and can involve analytic drill work on the perception of phonemes that are difficult for the adult with HI.
Lists of matched syllable and words that contain the troublesome phonemes, such as she- fee, so –tho, met- let, or mash-math, are read to the individual, who repeats them back. It also includes phrases and sentences. Speech reading combined with person’s hearing was also encouraged during a portion of the auditory training sessions.
Carhart advocated the auditory training sessions to be conducted in 3 commonly encountered situations:
– Relatively intense background noise
– Presence of competing speech signal
– Listening on the telephone
According to Carhart, the use of hearing aids is vital in AT, and he recommended that they be utilized as early as possible in the AT program. These recommendations were consistent with Carhart’s belief that systematic exposure to sound during AT was an ideal means of allowing a person to adequately adjust to hearing aids and assist in using them as optimally as possible.
In this approach focus is more on auditory training than auditory learning.
Auditory Training-mainly drill work with or without involving concept i.e. may be meaningful or non-meaningful.Auditory Learning– it is done meaningfully. So, in a real life situation, person is required to listen not only to verbal but also non-verbal. They do require getting information about both and needing both sides of the hemisphere to be stimulated.
3.4.4. Erber (1982):
A flexible and widely used approach to auditory training designed primarily for use with children has been described by Erber (1982). This adaptive method is based on a careful analysis of a child’s auditory perceptual abilities through the use of the GASP (Glendonald Auditory Screening Procedure) assessment battery.
The GASP’s approach to evaluate a child’s auditory perceptual skills takes into account two major factors:
– The complexity of the speech stimuli to be perceived (ranging from individual speech elements to connected discourse)
– The form of the response required from the child (detection, discrimination, identification, or comprehension).
Several levels of stimuli and responses are involved as shown in Figure 1.
Figure 1. An auditory stimulus-response matrix showing the three GASP subtests: Phoneme Detection (1), Word Identification (2), and Sentence (Question) Comprehension (3).
The GASP test battery evaluates only the three stimulus-response combinations indicated in the figure above. However, Erber encourages the use of other available test materials to evaluate other test materials to evaluate other stimulus-response combinations from the matrix in Figure 1 when appropriate. Once the child’s auditory capabilities are determined, an auditory training program is outlined using the same stimulus-response model as in GASP assessment, when establishing goals and beginning points for therapy. Erber’s approach is flexible and highly adaptable to children with a wide variety of auditory abilities, since the stimulus and response combinations range from the simplest (phoneme detection) to the most complex (sentence comprehension) perceptual tasks.
Erber also described three general styles which the clinician may use during auditory training, depending on the communication setting. These styles differ in specificity, rigidity, and direction, and are described as in Table 1.
Natural conversational approach
The teacher eliminates visible cues and speaks to the child in as natural a way as possible, while considering the general situational context and ongoing classroom activity.
The auditory speech perception tasks may be chosen from any cell in the stimulus-response matrix, for example, sentence comprehension.
The teacher adapts to the child’s responses by presenting remedial auditory tasks in a systematic manner (modifies stimulus and/or response), derived from any cell in the matrix.
Moderately structured approach
The teacher applies a closed-set auditory identification task, but follows this approach activity with some basic speech development procedures and a related comprehension task. Thus, the method retains a degree of flexibility.
The teacher selects the nature and content of words and sentences on the basis of recent class activities.
A few neighboring cells in the stimulus-response matrix are involved (for example, word and sentence identification and sentence comprehension).
Practice on specific tasks
The teacher selects the set of acoustic speech stimuli and also the child’s range of responses, prepares relevant materials, and plans the development of the task, all according to the child’s specific needs for auditory practice.
Attention is directed to a particular listening skill, usually represented by a single cell in the stimulus-response matrix (e.g., phrase discrimination).
Table 1. Three general auditory training approaches
Adaptive procedures, where the child’s responses to speech stimuli are used to determine the next activity, can be employed with any of these styles. In order to develop a child’s auditory abilities, Erber (1982) stated:
Auditory training need not follow a developmental plan where, for instance, you practice phoneme detection first and attempt comprehension of connected discourse last. Instead, you might use the “conversational approach” during all day conversation, and apply the “moderately structured approach” as a follow-up to each class activity. During each activity, you will note consistent errors. Later, you might provide brief periods of specific practice with difficult material. In this way, you can incorporate auditory training into conversation and instruction, rather than treat listening as a skill to be developed independently of communication.
Erber’s emphasis on integrating the development of auditory skills into all activities with children with hearing impairment is shared by many, including Sanders (1993) and Ling and Ling (1978), who recommend that auditory training “be viewed as a supplement to auditory experience and as an integral part of language and speech training”. Thus, therapy directed towards development of auditory and language skills can and should be done in an integrated, mostly seamless manner.
3.4.5 Developmental Approach to Successful Listening II (DASL-II):
Stout and Windle (1994) have developed a sequential, highly structured auditory-training program called Developmental Approach to Successful Listening II or DASL-II. Like Erber’s (1982) approach, the DASL II consists of hierarchy of listening skills that are worked on in relatively brief, individualized sessions.
The DASL II curriculum can be used with persons of any age, but mainly has been utilized with preschool and school-age youngsters using either hearing aids or cochlear implants. Three specific areas of auditory skill development are focused on:
– Sound awareness: deals with the development of the basic skills of listening for both environmental and speech sounds. The care/use of hearing aids and cochlear implants are also included.
– Phonetic listening: includes exposure to fundamental aspects of speech perception such as duration, intensity, pitch and rate of speech. The discrimination and identification of vowels and consonants in isolation and in words are included in this area.
– Auditory comprehension: emphasizes the understanding of spoken language by the child with hearing impairment. Includes a wide range of auditory processing activities from basic discrimination of common words to comprehension of complex verbal messages in unstructured situations.
As with GASP approach, information from the DASL II placement test enables the clinician to determine the appropriate placement of the child within the auditory skills curriculum. The test’s developers provided numerous activity suggestions for the clinician. These address each of the many sub-skills of the three main areas of listening which make up DASL II. These are organized from the simplest to the most difficult listening task.
A team approach is encouraged with DASL II, with the audiologist, speech-language pathologist, classroom teacher and parents working in a coordinated fashion on relevant subskills. This makes it vital that frequent communication occurs among the team members.
Clark and Watkins (1985) developed this comprehensive identification and intervention treatment program for infants with hearing impairment and their families, and it is in wide use. One of the major components of SKI-HI’s treatment plan is a developmentally based auditory stimulation-training program. It is utilized in conjunction with language-speech stimulation and consists of 4 phases and 11 general skills as shown in Table 2.
Attending:child aware of presence of home and/or speech sounds but may not know meanings; stops, listens, etc.
Early vocalizing: child coos, gurgles, repeats syllables, etc.
Recognizing:child knows meaning of home and/or speech sounds but may not be able to locate; smiles when hears Daddy come, etc.
Locating: child turns to, points to, locates sound sources.
Vocalizing with inflection: high/low, loud/soft, and/or, up/down.
Hearing at distances and levels: child locates sounds far away and/or above and below.
Producing some vowels and consonants.
Environmental discrimination and comprehension: child hears differences among and/or understands some sounds.
Vocal discrimination and comprehension: child hears differences (a) among vocal sounds, (b) among words, or (c) among phrases and/or understands them.
Speech sound discrimination and comprehension: child hears differences among and/or understands distinct speech sounds.
Speech use: child imitates and/or uses speech meaningfully.
Table 2. The four phases and eleven skills of the SKI-HI auditory program
The approximate time line indicates the estimated amount of time spent by a profoundly deaf infant in each phase.
Although these phases and skills are organized developmentally, infants may not always move sequentially from one phase or skill on the list to the next higher one in a completely predictable manner. SKI-HI provides an extensive description of activities which the clinician and parent or caregiver may utilize in working on sub-skills related to each of the specific general skills included in each phase of the auditory training program.
3.4.6. Traditional approach:
Hirsh and Ling(1976) have described 4 levels of audition that contribute to the perception of conversational speech, detection, discrimination, identification and comprehension.
– Detection: requires only the child should be able to distinguish between the presence and absence of sound
– Discrimination: involves differentiation of speech sounds.
– Identification: requires the child to recognize the speech signal and to be able to identify.
– Comprehension: involves understanding of the message on a cognitive and linguistic basis
Erber and Hirsh (1978) suggested an auditory training program in which increasingly complex speech stimuli are presented for processing through 4 levels of audition in Table 3.
The first 2 stages are not usually done. The suprasegmental part is not included here; it taps only long term memory. Mastery of the lower levels of detection and discrimination is considered to be the pre requisite for successful performance at the higher level of identification and comprehension.
Children should progress through the four levels and the various stimulus complexities at their own rate and to the extent dictated by the status of their residual hearing. The detection level in the matrix does not correspond to the awareness stage as proposed by Carhart, because it focuses on speech reception rather than awareness of the sounds in general.
Table 3. Model of Hirsh and Erber (1978) to assess and facilitate Auditory development.
In addition, there is no corollary in the Erber and Hirsh paradigm for the development of gross discriminations of non- speech sounds as proposed by Carhart.
3.4.7. Ling’s approach:
Training programme is based on:
– Acoustic characteristic of speech
– Emphasis on listening aided by amplification
– Involves segments as well as supra segmental
– Recognizes need to attain vocal system, respiration, motor control and coordination. Prior to use of speech in meaningful contexts.
Ling emphasized that speech should be taught at phonetic level rather than phonological level. Child’s ability to detect all six sounds demonstrates that ability to detect all aspects of speech.
3.4.8. Speech tracking /continuous discourse tracing:
Developed by DeFilippon Scott (1978) to provide perception practice with sentence length material referred to tracking. It involves a clinician to read short segment of story in an auditory only communication mode.
The HI adults then attempts to repeat verbatim what was read. When the listeners failed to repeat, the clinician selects one or more of series of strategies to help the listener achieve 100% recognition.
Strategies include repeating the words missed, repeating the words heard correctly, and using the synonym for the word missed .Strategies are selected at the clinicians’ discretion. Visual cues can be added for bisensory training. Performance is monitored by calculating the number of words correctly repeated by the listener per minute during a therapy session.
Speech tracking requires that patient (receiver) listen to segment of on-going speech usually taken from a written passage, spoken by a communication partner (sender) and then repeat the utterance verbatim.This can apply to any sensory modality.
3.4.8. Topicon (Erber 1988):
In this activity the patient or clinician chooses a topic of interest from a prepared list. Then patient and clinician carryout the conversation. The clinician assesses the fluency of the conversation on the basis of a number of presented variables known to influence conversational fluency and satisfaction.
For example the amount of speaking time taken by each person involved in the conversation, no. of conversational turns and no. of communication breakdown. After the communication is completed the patient and clinician discuss the success of the conversation, identifies source of difficulty and identify possible solution that might be implemented to overcome those difficulties.
Other activities include:
– Viewing and analyzing specific segments of video taped conversations, identifying the global characteristics of the conversation and judging the level of satisfaction experienced by the participants.
– Conversation activities such as speech tracking procedures, question and answer activities and topic centered conversation can be used to improve the conversational fluency (Erber 1988, 1996).
Moog, Biedenstein, and Davidson (1995) developed the Speech Perception Instructional Curriculum and Evaluation (SPICE) to provide a guide for clinicians in evaluating and developing auditory skills in children with severe to profound hearing loss. It contains goals and objectives associated with four levels of speech perception. The first level detection,is intended to establish an awareness and responsiveness to speech. The second and third levels, suprasegmentaland vowel and consonant perception, are worked on. In suprasegmental section children work on differentiating speech based on gross variations in duration, stress, and intonation. In the vowel and consonant section, children begin to make perceptual distinctions among individual word stimuli with similar duration, stress, and intonation features, but with different vowels and consonants. With progress, the child is introduced to the fourth level, connected speech. Now the emphasis is the perception of words in a more natural environment (phrases and sentences). Activities for SPICE are done with combined auditory-visual presentation, as well as auditory-only listening situation. As the child progresses, the newly acquired skills can be refined further in more natural, informal conversation. Recently, SPICE has been used extensively with children using cochlear implants as an approach to developing listening skills in conjunction with their expanded auditory input.
3.4.10 Auditory Learning-learning to listen:
Over the years, a lot of terminologies have been used to enable the individuals to use their auditory mechanism for communication. Some of the terms that have been used include auditory training, listening training, and acoustic training. These three are used interchangeably and the most commonly used term is auditory training.
The other terms used include auditory learning. There are also other approaches that have been given specific terminologies such as auditory verbal therapy (AVT), auditory-oral method, and aural-oral method. So it is required these terms be defined.
Auditory learning: It is one in which activities for developing spoken language are related to the children real life experience and language stresses the comprehension of meaningful sounds which is considered to be highest level of auditory behavior (Erber, 1982; Sanders, 1982).
Auditory-oral method: It’s a method to teach language both receptive as well as expressive to children with hearing impairment. Some believe that along with the auditory cue speech reading can also be carried out.
Aural-oral method: It is a method where the child develops/ taught language through the auditory mechanism and communicates through speech.
Result of Auditory training cases of children between 9 to 12 years of age:
Four right handed Monolingual English speaking children 2 males and 2 females were selected from the special school located nearby Sharjah, U.A.E to participate in the study. They ranged in age from 9.0 to 12.0 (years and months).They were between severe to profound sensorineural hearing loss with no other disability or abnormality. All the four cases were using bilateral hearing aids from the age of 3 to 5 years.
4.2. Assessment in Auditory training:
In order to plan effectively for auditory training it is important to assess the child’s auditory levelbefore beginning the training. Assessment can also be used to measure the progress achieved by the child so that the next step can be decided. It tells us the strengths and weakness of the child.
Before beginning the assessment, ensure that the hearing aids are functionally.
4.2.2. The Aided Audiogram
The aided Audiogram tells us the minimum levels of sound that the child can hear through the hearing aid at normal conversational distance-approximately 1 meter. The aided audiogram should ideally be at upper border of speech banana .This means that the child would be able to hear all the speech sounds which lie in the high frequencies, if the aided audiogram is in speech banana at low frequencies but drops below the speech banana at high frequencies,the child may miss hearing those speech sounds which lie in the high frequencies. A good aided audiogram does not ensure that a child will be able to understand all speech but it does give the therapist an idea what sounds the child is capable of detecting.
4.2.3. The Ling’s six sound test.
This simple test given by ling in 1970 can be administered very quickly to get an idea about the child’s ability to detect and identify speech sounds from low to high frequencies. Ling chose six sounds so as to include sounds from low, mid and high frequencies.The six sounds are /a/,/i/,/u/,/sh/,/s/and /m/
4.3 Procedure for Administration:
4.3.1. Awareness level:
The children were instructed to raise the hand when a sound is heard or keep a peg on the ear and put it in a box when a sound is heard .The children can be given practice for doing this with the therapist sitting infront of the child.Visual clues may be provided initially if required, the giving practice with covered mouth of the therapist .begin when the children have understood the test .To begin testing stand behind the children at a distance of 3 feet, say each sound in a normal voice and wait to see if children respond if a child is unable to hear a sound from 3 feet, present the sound near the children ears. This will help the therapist to understand the distance that should be maintained for the children to hear particular speech sounds.Sound intensity increases when distance is reduced.If a child hears all six sounds from 3 feet, go to distance of 5 feet and administer the sound. Results are noted in each case.
4.3.2. Identification level:
In this case children had to indicate which sound they heard. This could be done by getting the children to point out to the sound written on a paper by the therapist or by repeating it if children can say all the sounds.
The following toys/pictures can be used:
– A train for sound /u/
– A baby doll crying for /a/
– A car for /i/
– An aeroplane for /m/
– A snake for /s/
– A pressurecooker for /sh/.
The therapist should begin the test from a distance of 3 feet. Children responses are noted as correct or incorrect after presenting each sound.
The responses can be noted down in the following format.
a i u s sh m
The ling’s test is very quick and should be performed each day before beginning an auditory session. Besides telling us about auditory abilities of a child, it can also alert the therapist to a hearing id that has gone out of order.
4.3.3. Assessment of Auditory Speech Perception:
Children with normal hearing learn to speak correctlyby matching their own speech with that of adults around them. The ability to produce speech is closely linked to the ability to perceive speech .It is therefore logical that children with hearing impairment would show incorrect production of speech sound thatthey do not perceive adequately. The following test “Early Speech Perception test “designed by Ann Geers and jean Moog divides children into 4 categories depending on their ability to perceive speech.
Category 1 – No pattern Perception: At the lower end of this category are those who cannot even detect speech with the help of amplification. It also includes children who can detect speech but cannot differentiate auditory among speech patterns that differ grossly in terms of duration. (e.g., cat vs rhinoceros)
Category 2 – Pattern perception: Children in this category have developed minimal skills in perceiving speech.At the lower end of this category are those children who are just beginning to differentiate words or phrases differing in durational pattern in a closed set(i.e., among alimited choice).At the upper end are those children who can differentiate between words that differ in stress (e.g., apple vs tooth brush).
Category 3 – Same word identification: Children in this category demonstrate minimal ability to make use of spectral and into national information. They can discriminate among words or phrases in similar stress and durational pattern in a closed set only if the vowels are highly different. (e.g., Santa Claus vs Christmas tree)
Category 4 – consistent word identification: Children in this category use spectral information to a greater extent for discrimination.They can discriminate among single syllable set (i.e., the child has to choose the correct word from a choice of many words)e.g, bun, bowl,bite, back etc.
The essential pattern in auditory training is to begin at a level just above the present level of the child’s auditory abilities and then as the child achieves that level, target the next level of performance that the child is asked to discriminate becomes less and less. However the sequence is always detection, discrimination, identification and comprehension.
4.4 Activities done for Awareness level:
Opportunity to listen: Seeing, feeling and listening to various noise makers,rattles etc.The therapist makes a box called the “listening box”.Children are taught to put in toys that make noise and those that are quiet. As each toy is taken out of the box the therapist says whether the toy makes a sound or not. Imitation of the sound is also done. Giving of toy to children is done for manipulation. The toys that make sound are put to one side and the toys that make no sounds are put to the other side. With this children learn to associate the sound with its source.
Anticipating sound: Before the sound is made, the children attention is seek and they are asked to listen for the sound. Eg. Hold a coin above the metal tin, and tell the child you are going to drop it and there will be a sound to listen.Then dropping the coin and asking them if they listened.
Who has the noisy shaker? One child at a time gets a turn to do the listening part. All the kids stand in the row with one closed tin in each child’s hand. Some tins contain objects and thus makes noise while some are quiet.The child, whose turn it is goes to each child in a row, listens to the tin when it is shaken and says who has the noisy tins. Things kept in the shakers: coins, beads, grains, buttons, stones, sand etc.
Jumping frog: Each child is given a toy frog.Whenever he hears the therapist makes a croaking sound,the child must make the frog jump. Other similar activity was also done where the child pours water from a tumbler when sound is presented. Instead of using the sound /a/ or the sound of drum, it is more natural to say pour the water as the stimulus.This makes it natural and eventually the child also learns the meaning of the sentences.
4.5. Activities done for Discrimination level:
The basic pattern in discrimination activities is presenting two or three sounds one after the other and children had to say whether they are same or different beginning with sounds that are very different from each other and then going by step by step to sounds which differ more finely from each other.
4.6. Activities done for identification level:
In these activities children had to recognize the target sound,word or sentences.
These activities were done by using toys, pictures or written materials.Below are few activities done with children.
– Farmyard game: plastic toy is kept in abox and kept in front of the child.Farmyard model is kept in front of children.The therapist names an animal or bird and the child picks that one from the box and put it in farmyard increasing the number of different animals used and having more animal names which sounds similar is done to increase the difficulty level.
– Color the circles: drawing circles on a paper and keeping a set of crayons next to children. The therapist names the color and the children pick up the color and fill is a circle.
– Going to shopping activity: parents are asked to take their children to take them to supermarket and ask their children to put in basket whatever is asked for. E.g. Soap, Biscuits, milk, chocolates etc.
– Identification of words and sentences differing in duration :
(e.g., cat vs. rhinoceros/ Cat vs donkey/ The girl is playing with big doll vs the boy is crying/ The girl has doll vs the boy is crying/ The child can point to pictures when depict the word or sentences).
Note: the difficulty level is being increased by reducing the differences.
– Continuous vs discrete sounds: Eg: meow vs dog (the child picks up the correct animal picture or object)
– Continuous vs discontinuous sounds: meow vs bow bow(the child picks up the picture of cat or dog correctly)
– Sentences differing in rhythm: e.g.: She is a good girl vs Oh! Look at that rat.
– Words differing in vowels and consonants: E.g.: Santa Claus vs Christmas tree, Donkey vs Monkey, Ball vs Bat.
– Words differing in consonants by manner of articulation: E.g. bat vs man (non-nasal vs nasal), Big vs pig (voiced vs voiceless)
– Words differing in consonants by manner of articulation: E.g. tall vs call, Pick vs tick.
These tasks can be made further difficult by putting such words into phrases and sentences.
4.7 Activities done for comprehension level:
– Picture Description: The Therapist describes the picture while the children listen.
– Following directions: Children does drawing or does any other activity by following directions e.g. draw two balls. Draw any animal, etc.
– Conversation: This can be with relevance with a particular topic. E.g. Birthday of any child in the session, Discussing about birthday celebrations, etc.
– Guessing games: Guess who it is by providing clues one by one. E.g: “I am a large animal”, “I have a long nose”, “I have big ears” .etc. These games foster thinking skills besides working on auditory comprehension.
Since hearing loss is a hidden disability and in case of children hearing loss becomes handicap, if undetected and untreated, it will lead to speech and language development delay, social and emotional problems and academic failure. Hearing or sense of audition is a pre-requisite for normal speech and language development and its sustainment.
By detecting hearing loss as early as possible even as early as new born period with effective treatment and rehabilitation it reduces the handicapped condition as hearing impaired children possess the same biological capacity for learning speech and language as do normal hearing children for those with a significant amount of residual hearing the most natural and effective sensory modality is the auditory channel.
Early intervention permits the children with even severe to profound sensorineural hearing loss to progress through normal developmental sequences concerning the critical period from birth to 2 ½ or 3 years of age resulting in greater linguistic and academic gains than the intervention after 2 ½ to 3 years. There are certain periods in development when the organism is programed to receive and utilize particular type of stimuli and subsequently the stimuli will have gradually diminishing potency in affecting the organism’s development in the function represented. In the case of audition, it means that at a certain developmental stage auditory signals will be optimally received and utilized for important pre linguistic activities, but once that stage has passed, the effective utilization of these signals gradually declines.
With the beginning of hearing aid fitting the rehabilitation starts but it is not enough to learn to make maximum use of the information that a child is getting through hearing aid. Parents often wonder why their child is advised for intensive training. It is the duty of the therapist /teacher to make them understand and explain the importance of auditory training. Auditory training can be incorporated into all routine activities. If this is done, the child will learn to use his or her hearing in all context.it is important to make the child realize the importance of hearing in our lives, the ways in which we react to sounds and what different sounds mean to us. For this to happen auditory training should be meaningful in the sense that the stimuli used as well as the responses expected should be relevant to the child’s life. Using every opportunity to teach a child to listen will bring awareness for a sound. Talking about the sound also ensures language input. Once the child has been introduced to sound give him /her opportunity to practice listening to sound whenever there is chance so that the child slowly begins to recognize the sound. This kind of training method effectively combines auditory training and language stimulation.
This program believes in the use of speech as astimulus for auditory training.Processing of sounds such as drum,bells etc. happens in one part of the brain whereas speech is processed in another part of the brain.Thus training children only with non-verbal sounds will not automatically improve speech perception. To improve the ability of the child to recognize speech, speech sounds should be used as a stimulus during training. All children may not be able to reach the level of comprehension but the therapist should train the child to reach the maximum level the residual hearing allows. Incorporation of Auditory training into routine activities will help children to learn to use his or her hearing for listening in all contexts .This kind of training method effectively combines auditory training and language stimulation, after all one of the goals of Auditory training isto enable better language development.
Finally, from our observations we found out Auditory training tends to prove in an improvised task done by 4 of our recruited children than their regular class peers in terms of an applied level, whether in their efforts from a stimulus perspective (e.g., components of language, such as phonemes) or from cognitive perspective(e.g., whether maximally activates an auditory attention network).With hearing aid fitting marking as the beginning of the rehabilitation for scientific auditory training program,we focused on discovering the rules and implementing into useful applications and emphasizing the importance of active engagement with the tasks.However, listening to sounds, providing auditory,visual and verbal cues helped in improved performance of both top down cognitive processing and bottom up sensory processing and hence Auditory training is proven to be the most efficient, convenient, controllable, and flexible way for most people to improve their listening, language and literacy skill.
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