I am always fascinated by brain development research. Because of this type of research we know that there are specific time periods when children are better able to learn specific types of information. This type of research has also helped to show us the need to provide intervention to children with severe hearing loss and deafness as early as possible. In the past, but in some cases as recently as the 1970s, children who were born deaf went undiagnosed for many years, sometimes not until they entered school did the family learn there was a problem. In some cases these children were then diagnosed as mentally retarded and placed in institutions. Brain development research has taught us that the prime time to learn language is in the early years of life. Consequently, most of these undiagnosed children were not able to develop language skills.
Because of the research into brain development and how children acquire language, it is common practice for hospitals to administer the newborn hearing screener with all babies. Although the test is not foolproof and can produce a false positive in about 1% of the tests, it is a great way to detect hearing loss and deafness early on. In cases where there is a history of family deafness, research has shown a need for follow up tests every six months until the child is five.
Halpin, K., Smith, K., Widen, J., & Chertoff, M. (2010). Effects of universal newborn hearing screening on an early intervention program for children with hearing loss, birth to 3 yr of age. Journal Of The American Academy Of Audiology, 21(3), 169-175.