HEARING IMPAIRMENT

1 HEARING . IMPAIRMENT . Chapter 1. Introduction The Ear and Its Work damage to the inner ear, makes it difficult to tolerate T he sense of HEARING provides a background, loud sounds. which gives a feeling of security and For children with HEARING IMPAIRMENT , participation in life. It plays a critical role in the congenital or acquired before development of development of speech and language and in speech and language, normal speech development monitoring one's speech. is interfered with. The ear is a complex, but delicate structure With unilateral HEARING IMPAIRMENT also, designed to perform a variety of functions: to able there is difficulty in localizing sound, reduced to hear very soft sounds over a wide frequency speech discrimination.

2 Lower speech and language range as well as withstand the very loud sounds, to development in children has significant effect on discriminate between sounds that vary in pitch and their educational, linguistic and auditory perceptual loudness; to be able to locate the direction of arrival development. of a sound and in the presence of noise, to be able to switch on and off a sound of interest. The HEARING -impaired persons have in common, their difficulty in HEARING spoken and The human ear perceives simple tones in the other sounds.

3 They also depend on what they see range of 20 to 20,000 Hz and also complex signals which they supplement to what they hear. such as speech and music. Both types of signals are used in the assessment of HEARING loss. Assessment HEARING sensitivity of each ear is Impact of HEARING IMPAIRMENT measured separately and the severity/degree of Consequences of HEARING IMPAIRMENT will HEARING IMPAIRMENT / HEARING loss is generally depend on the ear/s involved, the degree and the classified in seven categories as per Goodman's type of HEARING loss and the age of onset.

4 (1965) classification and an additional category HEARING IMPAIRMENT leads to loss of normal - slight HEARING loss is added between the verbal communication. Due to distortion of normal HEARING and mild HEARING loss sounds, differentiation of environmental sounds, especially when assessing the HEARING including speech, is difficult; making sounds sensitivity of young children. Table 1 shows louder does not improve the clarity or quality of the classification of severity of HEARING sound. Similarly, recruitment, which is an IMPAIRMENT .

5 Abnormal growth in loudness, a characteristic of 99. Table 1: Classification of Severity of Percentage of HEARING Disability HEARING IMPAIRMENT (Threshold + Speech Discrimination Score Based). Classification PTA range in dBHL The Ministry of Social Justice and Normal HEARING -10 to 15 Empowerment, Government of India notified Slight HEARING Loss 16 to 25 guidelines for evaluation of various disabilities and Mild HEARING Loss 26 to 45. procedure for certification vide Notification No. Moderate HEARING Loss 46 to 55. 16-18/97-NI dated 1st June 2001.

6 Procedure for calculating HEARING disability is based on pure tone Moderately-severe HEARING Loss 56 to 70. thresholds as well as speech discrimination score Severe HEARING Loss 71 to 90. in order to arrive at the percentage of the disability. Profound HEARING Loss 91 and more The minimum degree of disability should be 40%. in order to be eligible for any concessions/ benefits. The level of normal conversational speech is approximately 65dBSPL. Thus, for a person with Issue of Disability Certificate HEARING IMPAIRMENT of 60dBHL or more, verbal The certificate of disability is to be issued by communication would be difficult.

7 This level of a medical board consisting of at least three HEARING IMPAIRMENT has been equated as 40%. members, of which one shall be an HEARING IMPAIRMENT as in Persons with Disability otolaryngologist. Percentage of disability can be (Full Participation, Equal Opportunity and determined considering Pure Tone Average and Protection of Rights) Act, 1995. The definition of Speech Discrimination Score as shown in Table 2. HEARING disabled as stipulated in the PWD Act, 1995. is a person who has a minimum of 60dBHL of HEARING IMPAIRMENT in the better ear in speech conversation frequencies.

8 Table 2: Percentage of Disability Category Type of PTA of Better Speech Discrimination Percentage IMPAIRMENT Ear in dBHL Score of Better Ear of Disability I Mild 26-40 80-100% < 40%. II(a) Moderate 41-60 50-80% 40-50%. II(b) Severe 61-70 40-50% 51-70%. III(a) Profound 71-90 <40% 71-100%. III(b) Total >91 Very Poor 100%. To obtain Speech Discrimination scores, nor standardized tests for speech discrimination in specialized skills, instruments and standardized various languages are presently available in all tests are required. Neither the range of instruments centers in the country.

9 100. Chapter 2. Historical Perspective H istorical developments have been dealt with comprehensively in the Disability Status Reports published by the RCI, in 2001 and 2003. mean that any effort to initiate early intervention services should be accompanied by short term training programs for qualified professionals. Since then, significant events such as establishment These programs should be aimed at equipping and support of early identification and early rehabilitation professionals to handle aspects intervention centers by the AYJNIHH, Mumbai especially pertinent to very young children.

10 And the Disability Helpline initiated during 2004- Keeping these issues in view, the project was 05 are worthy of mention. evolved. The project was conceptualized in two phases: Establishment of Early Intervention Phase I: Training of manpower to enable Centers and Training of Personnel them to handle very young A collaborative project by AYJNIHH, children. Mumbai and Balavidyalaya, Chennai on Early Identification and Early Intervention towards Phase II: Running the early intervention Inclusive Education of Children with HEARING programs.