“…Studies have shown that when a hearing loss begins to exceed 55 dB in the high frequencies, participants may not benefit from highfrequency amplification (Moore, 2001). This lack of benefit of high-frequency amplification has been attributed to limitations of the hearing aid in the form of restricted bandwidth, low maximum output, or feedback before the necessary level of amplification is reached (Stelmachowicz et al, 2001;Auriemmo et al, 2009) as well as the existence of dead regions, that is, areas of the cochlea with no functioning inner hair cells (Moore, 2001;Baer et al, 2002;Preminger et al, 2005). Studies on speech perception in people with suspected high-frequency dead regions have shown that amplification of the high frequencies often fails to provide benefit and may in fact lead to poorer performance in some instances (Ching et al, 1998;Hogan & Turner, 1998;Turner & Cummings, 1999).…”