It is widely accepted that the critical period for speech and language development is from birth to three years of age. This critical age concept was given by Lenneberg (1967).
According to this, language is biologically innate and there is an optimum time for its development. Hearing loss during this critical period can have adverse effect in speech and language development causing adverse effect on social development. Lack of auditory information due to hearing loss, also affects neural development of the auditory pathways and leads to auditory deprivation.
A child communicates the needs through speech modality. When the child struggles to communicate due to hearing loss, there exists psychological frustration. Earlier the hearing impairment diagnosed, sooner can the early intervention begin, to prevent the negative impacts of hearing loss.
How early should we identify hearing impairment???
A few researchers have examined the benefits of early diagnosis of hearing loss and early intervention. Yoshinaga, Sedey, Coulter, and Mehl (1999) examined 150 deaf and hard of hearing children. The ages ranged from 1 year 1 month to 3 years 0 months. They concluded that the group of children who have been diagnosed before 6 months of age were having significantly better speech and language skills compared to another group. In addition, for normal cognitive development, the finding was evident across all test ages, communication modes, degrees of hearing loss, and socioeconomic strata. Also, the finding was independent of gender, minority status, and the presence or absence of additional disabilities.
Robinshaw in his longitudinal study to examine the impact of early intervention in the hearing-impaired children., he concluded that Children having severe and profound hearing impairment and were fitted with amplification device before six months of age showed communicative and linguistic skills remarkably similar to their normally hearing peers. He suggested that a delay in the fitting of amplification device for as little as 3 to 6 months was enough to cause a significant delay in speech and language acquisition.
The listening Age of the child must match with the biological age. When the implantation happens at the age of 2months to 6 months, the hearing-impaired child does not lag behind on the communicative skills.
The most important tool to help the hearing-impaired person surmount the hearing handicap is a hearing aid or educational amplification unit. No system of amplification can restore hearing, but it can make useful residual hearing which could not otherwise be reached.
• Hearing Aids- Body-level, BTE, ITE, ITC aids, BC hearing aids.
• Implantable Devices- Cochlear Implants, BAHA, Middle-ear Implants, Auditory-brainstem implants, Auditory Mid-brain implants.
• Group Amplification Devices- Hard wire, Induction loop, FM, Infra-red, etc
Why auditory training after hearing amplification or implantation???
The child who is trained to use his residual hearing to the fullest extent develops a better understanding of the relationship between sounds and objects, sounds and actions, sounds and people and he begins to associate the sounds of speech with the language he has learned. This leads to better speech and more comprehensive grasp of language.
Traditionally auditory training has been considered a major component of the audiologic rehabilitation process. Most traditional approaches to auditory training use a hierarchy for auditory skill development (Erber 1982). The hierarchy includes awareness, discrimination, identification, and comprehension. This, to date forms the skeleton of auditory training.
Hierarchy of Listening skills
Within each areas of listening, there are four levels of auditory skill, which are sequential and overlapping.
1.DETECTION is the ability to respond to the presence or absence of sound. It is the first step in listening. In this stage the child learns to respond to sound, how to pay attention to sound, and not to respond when there is no sound.
To build up the child’s conditioned response to a stimulus and to find out changes in the child’s responses to detection task.
To detect possible middle ear dysfunction and associated temporary decrease in hearing levels, hearing aid malfunctions, or changes in the acoustic properties of ear mold.
2.DISCRIMINATION is the ability to recognize similarities and differences between two or more stimuli. The child learns to attend to differences among sounds, or to respond differently to different sounds.
E.g., When a child confuses the singular and plural “dog” and “dogs”, the therapist may present the pairs dog-dog, dog-dogs, dogs-dogs and ask the child whether the words are same or different and the “s” is audible to the child, then some word discrimination activities may be useful.
3.IDENTIFICATION/RECOGNITION is the ability to reproduce a speech stimulus by naming or identifying through picture pointing, by writing, or by repeating the speech heard. It includes practice of both suprasegmental and segmental aspects of speech.
(a). Supra Segmentals
i. Prosodic features of speech
The auditory identification of prosodic features is most easily learned through imitation of prosody. The therapist presents a speech pattern (e.g., A loud voice or rising speech pattern) through listening only., and then ask the child to produce the same pattern. Reinforcement is provided for the correct imitation of the prosodic pattern.
ii. Loudness & Pitch
Teaching the classification of loudness and pitch separately (high-low or loud-soft) is followed by differentiation of paired loudness-pitch characteristics, such as loud-high versus loud –low voices. The therapist needs to ensure that the child has the linguistic ability to describe loudness and pitch parameters. To make it interesting, the activities may be created using puppets in which one puppet has a high-pitched voice and the other has a low-pitched voice. The therapist may then alter the loudness of each of the puppet’s voices to create paired voice characteristics, and the child selects the correct puppet and identifies the voices as loud or soft.
iii. Angry and sad voices
The child is asked to add meaning to changes in loudness, duration, and pitch characteristics in voices. Instead of labeling a voice as high-loud or low-soft, the child learns to find the emotional content of a person’s voice as angry or sad. The child can imitate the speaker’s voice and body language to integrate the reception and production of appropriate prosodic features. Use of puppets, role playing, and tape recordings are especially useful.
iv. Male, female and children’s voice
Children who have begun using cochlear implants at a young age appear to acquire this auditory distinction naturally. To ensure a transition from the easiest to most difficult auditory comparison begins by contrasting male and children’s voices (125Hz versus 325Hz), then male and female voices (125Hz versus 250Hz), followed by female and children’s voices (250Hz versus 325Hz), and finally by comparing male, female and children’s voices. Children begin by listening to familiar male and female voices. Use of tapes of family member’s voices can generalize this auditory skill to the everyday environment.
Identification of segmentals (vowels and consonants) requires more functional hearing than the identification of suprasegmental information.
Initial sound vocabulary
Therapist can begin with different sounds including onomatopoeic sounds. He may use “meow” for the kitten. “ah” for the airplane, ‘bu-bu-bu” for the bus, and “oo-oo-oo” for the train. Each of these sounds is presented with the associated toy during therapy and in play activities in the home. Parents are encouraged to expose children to these sounds in as many natural language situations as possible.
Two critical elements in a phrase
This activity can be illustrated with prepositional phrases such as “show me the cow behind the barn”, “show me the book on the table”, “show me the toy under the bed” moving from a closed set to an open repetition task over time. The child must be familiar with the vocabulary embedded within the two critical elements of the phrase.
A hierarchy of listening skills keeping comprehension activities last is misleading and is only a theoretical concept that permits ordering of skills. Parents of young children are encouraged to develop simple comprehension activities concurrently with identification activities as a part of natural communication.
Familiar expressions and common phrases
It may include expressions such as “Be careful”, “Wait a minute”, “Shhh…baby is sleeping” etc. this can be conducted at the comprehension (to perform the task) or the identification (to select a card demonstrating the action) level. Parents may give the therapist an array of common expressions used in their home, so that carryover from clinic to home can be maximized.
Single directions and Two directions
For young children, those directions may concern manipulation of objects (“Give me some bread”, “Make the bird hop”) in a closed-set task, or some action for the child to perform (“Close the door”, “Brush your teeth”) in an open-set task within a structured setting. Once the child has mastered the skill in a structured task, the therapist or parent can introduce the activity as a spontaneous part of each session. Activities involving two directions may follow mastery at the level of single directions.
This is a brief overview of Auditory Training. At BCII we have a dedicated team for Auditory verbal therapy, that starts soon after Cochlear Implantation for patients who are implanted at our center and also other centers. We ensure the child’s communication matches with the peers and provide necessary help throughout the hearing journey. Connect with us through our email firstname.lastname@example.org, Ph:6366888883.