ABSTRACT
The World Health Organization (2002) (Facts about Deafness, 2004) estimates that 250 million people in the world function with a disabling hearing loss. The presence of an uncorrected hearing loss serves to reduce an individual’s level of participation in work, home, school, family, and social domains. The consequences may result in poorer academic outcomes, decreased vocational opportunities, social isolation, and depression (Keller et al., 1999; Karchmer and Allen, 1999). Assistive technology for this population is referred to as hearing assistance technology (HAT). HAT devices are designed to either enhance the degraded auditory signal caused by the hearing loss or to substitute the degraded auditory signal via alternative modes of information input (mainly visual or tactile).
