Kirby Benjamin J, Kopun Judy G, Spratford Meredith, Mollak Clairissa M, Brennan Marc A, McCreery Ryan W
Department of Communication Sciences and Disorders, Illinois State University, Normal, IL.
Boys Town National Research Hospital, Omaha, NE.
J Am Acad Audiol. 2017 Oct;28(9):810-822. doi: 10.3766/jaaa.16157.
Sloping hearing loss imposes limits on audibility for high-frequency sounds in many hearing aid users. Signal processing algorithms that shift high-frequency sounds to lower frequencies have been introduced in hearing aids to address this challenge by improving audibility of high-frequency sounds.
This study examined speech perception performance, listening effort, and subjective sound quality ratings with conventional hearing aid processing and a new frequency-lowering signal processing strategy called frequency composition (FC) in adults and children.
Participants wore the study hearing aids in two signal processing conditions (conventional processing versus FC) at an initial laboratory visit and subsequently at home during two approximately six-week long trials, with the order of conditions counterbalanced across individuals in a double-blind paradigm.
Children (N = 12, 7 females, mean age in years = 12.0, SD = 3.0) and adults (N = 12, 6 females, mean age in years = 56.2, SD = 17.6) with bilateral sensorineural hearing loss who were full-time hearing aid users.
Individual performance with each type of processing was assessed using speech perception tasks, a measure of listening effort, and subjective sound quality surveys at an initial visit. At the conclusion of each subsequent at-home trial, participants were retested in the laboratory. Linear mixed effects analyses were completed for each outcome measure with signal processing condition, age group, visit (prehome versus posthome trial), and measures of aided audibility as predictors.
Overall, there were few significant differences in speech perception, listening effort, or subjective sound quality between FC and conventional processing, effects of listener age, or longitudinal changes in performance. Listeners preferred FC to conventional processing on one of six subjective sound quality metrics. Better speech perception performance was consistently related to higher aided audibility.
These results indicate that when high-frequency speech sounds are made audible with conventional processing, speech recognition ability and listening effort are similar between conventional processing and FC. Despite the lack of benefit to speech perception, some listeners still preferred FC, suggesting that qualitative measures should be considered when evaluating candidacy for this signal processing strategy.
倾斜性听力损失限制了许多助听器使用者对高频声音的可听度。助听器中引入了将高频声音转换为低频声音的信号处理算法，以通过提高高频声音的可听度来应对这一挑战。
本研究考察了成人和儿童在使用传统助听器处理方式以及一种名为频率合成（FC）的新型降频信号处理策略时的言语感知表现、聆听努力程度和主观音质评分。
参与者在初次实验室访视时，以及随后在家中进行的两次为期约六周的试验中，在两种信号处理条件下（传统处理与FC）佩戴研究用助听器，条件顺序在双盲范式中对个体进行平衡。
双耳感音神经性听力损失的全职助听器使用者儿童（N = 12，7名女性，平均年龄12.0岁，标准差 = 3.0）和成人（N = 12，6名女性，平均年龄56.2岁，标准差 = 17.6）。
在初次访视时，使用言语感知任务、聆听努力程度测量和主观音质调查来评估每种处理方式下的个体表现。在每次后续家庭试验结束时，参与者在实验室进行重新测试。以信号处理条件、年龄组、访视（家庭试验前与家庭试验后）以及助听可听度测量作为预测因素，对每个结果指标进行线性混合效应分析。
总体而言，FC与传统处理之间在言语感知、聆听努力程度或主观音质方面，以及在听众年龄影响或表现的纵向变化方面，几乎没有显著差异。在六个主观音质指标中的一个上，听众更喜欢FC而非传统处理。更好的言语感知表现始终与更高的助听可听度相关。
这些结果表明，当通过传统处理使高频言语声音可听时，传统处理与FC之间的言语识别能力和聆听努力程度相似。尽管对言语感知没有益处，但一些听众仍然更喜欢FC，这表明在评估这种信号处理策略的适用性时应考虑定性指标。
