Music, Spoken Language, and Children with Hearing Loss: Definitions and Development

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In the United States alone, 24,000 babies are born annually with a permanent hearing loss, making it the country's number one congenital birth defect (Beginnings, 2009). Hearing loss puts children at risk for delays in acquiring the necessary spoken language, social and cognitive skills needed to succeed in school and society (National Center for Hearing Assessment and Management, NCHAM; 2010). However, in areas with universal newborn hearing screening (UNHS), many of these children are now identified at birth and receive a complete diagnosis by three months and intervention by six months of age (Harrison, Roush, & Wallace, 2003). This early intervention has a tremendous positive impact on their future prognosis. Given that the overwhelming majority (>90%) of these children are born to hearing parents (Nicholas & Geers, 2007), many are enrolled in aural/oral programs with the ultimate goal of providing access to all the advantages their hearing peers enjoy. Certainly music enjoyment and participation would be one such advantage! Technological advancements in hearing aids (HA) and cochlear implants (CI) have opened the door even further for many of these children. In this article, hearing loss will be briefly defined, music and language development in typically hearing children will be discussed, the commonalities and differences between both domains will be examined, and current research regarding music and children with hearing loss will be highlighted.

Hearing Loss

Hearing loss can occur bilaterally (both ears) or unilaterally (one ear). It can be symmetrical, meaning both ears have the same degree and configuration of loss, or asymmetrical, where each ear is different. It can occur suddenly or progress over a period of time and the loss can fluctuate, as in the case of an ear infection. It is estimated that 30-40% of individuals with a hearing loss have other complicating factors (Almond & Brown, 2009; Robbins, 2009).

Range of Loss

To determine the degree of an individual's hearing loss, an audiologist will measure a person's hearing threshold, or the softest sounds a person hears at different frequencies (pitches) about 50% of the time. Intensity (loudness) is measured in decibels (dB) and frequency (high/low pitch) is measured in Hertz (Hz). Figures 1 and 2 illustrate how intensity and frequency relate to hearing. Plotted on a graph called an audiogram, intensity is on the vertical axis of the graph and frequency across the top.



Click Here to View Larger Version of Figure 1 and Figure 2

The severity of a hearing loss typically falls into four categories, mild, moderate, severe, and profound. A mild loss means that any sound softer than 25-40dB will not be detected. A child with this loss will have trouble hearing speech in a noisy environment. Faucets dripping and birds chirping may not be heard. A moderate loss of 40-65dB means speech will only be understood if it is spoken loudly. Environmental sounds like a vacuum cleaner may not even be heard. A severe loss means sounds softer than 65-90dB will not be detected. Speech will only be heard if shouted into the ear. Dogs barking or phones ringing may be missed. With a profound loss no speech will be heard. An airplane can fly overhead undetected, unless the child actually sees it.