The Effects of Non-Linear Frequency Compression on Speech Recognition1

  • Research type

    Research Study

  • Full title

    The Effects of Non-Linear Frequency Compression on Speech Recognition in Adults with Hearing Loss

  • IRAS ID

    206300

  • Contact name

    Richard Baker

  • Contact email

    richard.baker@manchester.ac.uk

  • Sponsor organisation

    Faculty of Biology, University of Manchester

  • Duration of Study in the UK

    0 years, 7 months, 18 days

  • Research summary

    The Effects of Non-Linear Frequency Compression on Speech Recognition in Adults with Hearing Loss

    High frequency (pitch) hearing loss is the most prevalent type of hearing loss in Great Britain. Non-linear frequency compression (NLFC) aims to improve the audibility of high frequency speech cues provided by hearing aids by compressing high pitch sounds into lower pitches where the listener’s hearing is better. NLFC is currently used in several types of hearing aids fitted by the NHS, but only two studies have shown that NLFC causes any improvement in recognition of whole words rather than individual consonants and there are no studies investigating whether speaker gender influences NLFC effects on speech recognition. There is also a lack of consensus regarding how to optimise NLFC settings.

    This study is for a dissertation in an MSc Clinical Sciences degree and aims to use speech recognition testing to investigate whether frequency compression improves speech recognition by addressing the following research questions:

    1. Which parts of words (phonemes) presented in sentences is recognition of most affected by NLFC?
    2. Does speaker gender influence the effects of NLFC on speech intelligibility?
    3. Is there any relationship between how well NLFC settings maximise the range of pitches audible to the participant and the effects of NLFC on phoneme recognition?

    This study will be of clinical benefit by improving identification of candidates for NLFC and helping to determine the extent to which NLFC improves understanding of speech. Participants will be adults who currently use Phonak hearing aids with NLFC enabled and are current patients of Bradford Royal Infirmary audiology department. They will be invited to attend an additional appointment during which their hearing aids will undergo routine maintenance and will then be asked to listen to sentences read by male or female speakers with NLFC enabled or disabled.

  • REC name

    HSC REC A

  • REC reference

    16/NI/0198

  • Date of REC Opinion

    21 Sep 2016

  • REC opinion

    Further Information Favourable Opinion