“The sense of hearing provides a background, which gives a feeling of security and participation in life. It plays a critical role in the development of speech and language and in monitoring one’s speech. The ear is a complex, but delicate structure designed to perform a variety of functions: to be able to hear very soft sounds over a wide frequency range as well as withstand the very loud sounds, to discriminate between sounds that vary in pitch and loudness; to be able to locate the direction of arrival of a sound and in the presence of noise, to be able to switch on and off a sound of interest. The human ear perceives simple tones in the range of 20 to 20,000 Hz and also complex signals such as speech and music. Both types of signals are used in the assessment of hearing loss.
“360 million people worldwide have disabling hearing loss” (WHO, 2015). The prevalence of deafness in India is fairly significant. It is the second most common cause of disability. “Approximately 63 million people (6.3%) in India suffer from significant auditory loss”. (Sulabha, Mahendra & Akriti, 2013)
As per the study on children of 0 to 6 years conducted by Voice of Voiceless organization in Solapur District using a cost efficient test called “Taat Waati Chachni”, 89 kids were identified with hearing impairment.
VOV has come up with a cost effective and innovative hearing ability test. The test could easily be implemented by anybody, as it includes only 2 easy tasks 1) is to take a metal bowl and a plate 2) Clang it on one another when the child is occupied with some other game. If the child could not hear the sound he/she is identified to be having hearing disability and further is referred for advanced scientific test. The test is specifically designed like this because it could be easily conducted by an Aanganwadi worker. An Aanganwadi worker is expected to visit the houses in his/her village and conduct the test on a child. The sole purpose of this test is to diagnose the hearing disability before the child reaches 2 years of age, so that the child could be given a training to learn speaking. This test could not only diagnose the hearing disability at the earliest but also could help in referring the child for an advanced hearing ability test called ‘BERA Test’. A BERA (Brainstem Evoked Response Audiometry) test technologically measures the central auditory pathways in the brain.
Consequences of hearing impairment will depend on the ear/s involved, the degree and the type of hearing loss and the age of onset. Hearing impairment leads to loss of normal verbal communication. Lower speech and language development in children has significant effect on their educational, linguistic and auditory perceptual development. The hearing-impaired persons have in common, their difficulty in hearing spoken and other sounds. They also depend on what they see which they supplement to what they hear.