Hearing tests for newborns are of late becoming a norm rather than an exception. Hearing screening is conducted before the baby is discharged from the hospital or maternity center. In the absence of such screening practices any hearing loss would only be detected at or after around 14 months.
The importance of hearing tests for newborns may not be very apparent to most of us, but it does play an important role. When there is a delay or late detection of hearing loss it can be damaging as this already implies delays in language development. Late detection of hearing loss or even failure to test for hearing problems can result in several problems for the child later as children suffering from undetected hearing loss would most likely perform poorly and be very likely to be held back. Children whose hearing disabilities are not detected early on are also a lot more likely to suffer greater academic failure and thus drop out of school. It should be pointed out that these patterns are in sharp contrast to those where the child's hearing loss has been diagnosed early on.
The hearing tests for newborns involve screening procedures that can identify bilateral or unilateral, and sensory or conductive hearing loss, both permanent and fluctuating with an average of 30 to 40dB or more. This is in reference to the frequency region that is crucial to speech recognition. Hearing tests for newborns involve the use of screening techniques that are non-invasive and physiologic measures, such as the otoacoustic emissions test or OAEs and the auditory brainstem response or ABR. These procedures are painless and cause no discomfort. They can in fact be performed while the baby is sleeping.
Otoacoustic emission tests involve the use of inaudible sound emissions from the cochlea upon stimulation of the cochlea with audible sound. This causes vibrations in the hair cells on the outer region of the cochlea, and the vibrations cause an inaudible sound to be produced, which echoes through the middle ear. A small probe is used to measure the sound, by inserting it into the ear canal. The emissions that are measured would only be produced in the ear of someone with normal hearing. The Auditory brainstem response is another one of the hearing tests for newborns. Electrodes placed on the head and are used in the measurement of brain wave activity in response to sound. This method of testing would also help in detecting a variety of hearing loss problems.