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Frequency Lowering in Hearing Devices Frequency Lowering Fitting Assistants (Java Script) Candidacy, Selection, and Verification of SoundRecover Options 3rd Phonak Virtual Audiology Conference (May 12, 2009) Video Replay and Slides A New Technique for Verifying Frequency Shifting Work by Stelmachowicz and colleagues demonstrate that the limited bandwidth of hearing aids prevents useful high-frequency speech information from being transmitted. This is especially problematic for children with mild-to-moderate hearing loss who are learning speech and language. The tubing resonances associated with behind-the-ear hearing aids, which are the only option for children, keep the limit of usable amplification well below 5-6 kHz. In addition, children with hearing loss cannot hear their own productions of these sounds with conventional hearing aids and are delayed in acquiring them in their phonetic inventory. The focus of one investigation is on a novel forms of frequency lowering techniques intended for precipitous hearing loss. Current hearing aid signal processing options are limited for individuals with precipitous hearing loss. Frequency lowering may increase the usable information within narrow bandwidths of audibility; however, preserving low-frequency information while recoding high-frequency information is a challenge. The goal of this research is to explore different ways of remapping high frequencies to perceptually enhance acoustic differences between highly confusable consonants. Future directions will investigate the effects of training and the feasibility of applying them to less severe hearing loss. Study results will inform manufacturer decisions on how to implement frequency lowering. The focus of another investigation is on the efficacy of products on the market that recode high-frequency information in lower frequency regions. Collaborative research carried out by Pat Stelmachowicz at Boys Town National Research Hospital (Omaha, Nebraska) investigates the efficacy of frequency lowering in adults and children with mild-to-moderate to severe SNHL of varying configurations on measures of speech perception, reaction time, clarity of speech and music, and speech production.

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