Rader Tobias, Doms Philipp, Adel Youssef, Weissgerber Tobias, Strieth Sebastian, Baumann Uwe
a Division of Audiological Acoustics, ENT Department , University Hospital Frankfurt , Frankfurt , Germany.
b Audiological Acoustics Division, Department of Otolaryngology, Head and Neck Surgery , University of Mainz , Mainz , Germany.
Int J Audiol. 2018 Jul;57(7):502-509. doi: 10.1080/14992027.2017.1412519. Epub 2018 Feb 1.
A psychoacoustic procedure designed for the precise assessment of perceptional threshold (T-level) in cochlear implant (CI) users is presented. The impact of this procedure on speech perception was investigated.
Individual T-level measurements were obtained with the proposed procedure and three different speech processor fitting conditions were applied: (1) fitting familiar to the subject, T-levels unchanged, (2) T-level set to thresholds determined with the new procedure, (3) T-level set to thresholds determined with the new procedure, but T-level is decreased by 10 clinical units (CU). The impact of the different fitting conditions was measured by means of categorical loudness scaling (CLS) and speech perception tests in quiet and noise.
A prospective study at a tertiary referral university hospital. 18 experienced postlingually deafened cochlear implanted adult subjects.
Average sound-field thresholds obtained by CLS were lowest in condition using the new procedure yielding a larger dynamic range with significantly higher speech scores in quiet compared to those with a subject's commonly used programme, and significantly improved in noise even after reducing T-levels by 10 CU.
The precise determination of T-levels by means of the proposed procedure improved performance in several speech recognition tasks. Compared to the default behavioural setting, T-level increased on median by 9 CU. Average speech reception threshold in noise for soft speech levels (50 dB sound pressure level) decreased by 1 dB.
介绍一种为精确评估人工耳蜗（CI）使用者的感知阈值（T值）而设计的心理声学程序。研究该程序对言语感知的影响。
采用所提出的程序获得个体T值测量结果，并应用三种不同的言语处理器适配条件：（1）受试者熟悉的适配，T值不变；（2）T值设置为用新程序确定的阈值；（3）T值设置为用新程序确定的阈值，但T值降低10个临床单位（CU）。通过分类响度标度（CLS）以及安静和噪声环境下的言语感知测试来测量不同适配条件的影响。
在一所三级转诊大学医院进行的前瞻性研究。18名有经验的语后聋人工耳蜗植入成年受试者。
通过CLS获得的平均声场阈值在使用新程序的条件下最低，与受试者常用程序相比，产生了更大的动态范围，在安静环境下言语得分显著更高，并且即使在T值降低10 CU后，在噪声环境下也有显著改善。
通过所提出的程序精确确定T值可提高多项言语识别任务的表现。与默认行为设置相比，T值中位数增加了9 CU。软言语水平（50 dB声压级）在噪声环境下的平均言语接受阈值降低了1 dB。
