We will examine your hearing ability by letting you listen to a number of different pure tones through a pair of headphones or earplugs, and with bone vibrator. Each ear will be tested individually. When you hear a tone, you press a button or raise your hand. The test results - illustrated as a graph or an audiogram - show your hearing threshold, i.e. the softest sounds you are able to hear at different frequencies (Hz).
This behavioural test are also called site of lesion test. These tests are specially done to differentiate between sensory function from the neural function. It is done only for the adult patient. These tests are used as a screening procedure in the auditory test battery.
The middle ear test shows how the ear drum reacts to varying air pressure in the ear canal. A small probe is inserted into the ear, and while listening to different sounds the air pressure inside your ear is increased or decreased. Your hearing ability depends on the degree of your ear drum sensitivity, and this test, in conjunction with the pure tone test and the speech test, helps the examiner to determine the extent of your hearing loss.
Some children do not accept that a headphone is put on their head or insert earphones are inserted in their ear. The only way to conduct an audiometric evaluation is to present sounds by means of loudspeakers. One more difficulty is to make the child respond to a sound which is audible to the child. This is achieved by connecting sounds and observe for behavioural changes. The procedure is called Behavioural observation Audiometry, every time after a sound is presented child will exhibit some kind of behaviour. An audible sound makes the child looking for the source. Therefore, every search reaction following a sound suggests that the previous sound was audible. For hearing instrument benefit evaluation, BOA is done twice: first without and then with hearing instrument.
Otoacoustic emissions are clinically important because they are the basis of a simple, non-invasive, test for hearing defects in newborn babies and in children who are too young to cooperate in conventional hearing tests.
The ABR is used for newborn hearing screening, auditory threshold estimation, intraoperative monitoring, determining hearing loss type and degree, and auditory nerve and brainstem lesion detection.