Hegarty Lauren, Faulkner Andrew
Cochlear Implants Int. 2013 Nov;14 Suppl 4:S35-9. doi: 10.1179/1467010013Z.000000000132.
This study investigated whether low frequency information from a hearing aid improved the perception of stress and intonation by English-speaking children with cochlear implants. As pitch information is limited for cochlear implant users, this study also investigated if users rely more on the cues of duration and amplitude to perceive stress and intonation.
Nine children with bimodal stimulation (cochlear implant and hearing aid) participated in two experiments. The first measured the just audible change in F0 (pitch) and amplitude for a speech-like word 'baba'. The second experiment examined the children's ability to identify focus in natural and manipulated sentences.
Overall, group results did not show a bimodal advantage in perceiving stress and intonation. However, the children were significantly better at perceiving focus in sentences with natural speech compared with manipulated speech in both the CI and bimodal conditions. The results suggest that in the absence of pitch cues, amplitude and duration cues are used to perceive stress and intonation. However, the majority of children only perceived amplitude changes greater than the changes typically found in speech, implying duration cues were the most valuable.
Taken together the findings suggest that for children with cochlear implants, cues to F0 may not be essential for prosody perception and in the absence of cues to F0 and amplitude, duration may offer an alternative cue.
Although a bimodal advantage was not demonstrated for all participants, it is recommended that if clinically appropriate, a contralateral hearing aid is fitted and trialled to exploit any residual hearing.
本研究调查了助听器的低频信息是否能改善使用人工耳蜗的英语儿童对重音和语调的感知。由于人工耳蜗使用者的音高信息有限，本研究还调查了使用者是否更多地依赖时长和幅度线索来感知重音和语调。
九名接受双模刺激（人工耳蜗和助听器）的儿童参与了两项实验。第一项实验测量了类似语音的单词“baba”的基频（音高）和幅度的刚可听变化。第二项实验考察了儿童识别自然句和人工句中焦点的能力。
总体而言，组内结果并未显示出在感知重音和语调方面的双模优势。然而，在人工耳蜗和双模条件下，与人工句相比，儿童在感知自然句中的焦点方面明显更出色。结果表明，在没有音高线索的情况下，幅度和时长线索被用于感知重音和语调。然而，大多数儿童仅能感知到大于语音中通常出现的变化的幅度变化，这意味着时长线索是最有价值的。
综合研究结果表明，对于人工耳蜗植入儿童，基频线索对于韵律感知可能并非必不可少，在没有基频和幅度线索的情况下，时长可能提供一种替代线索。
尽管并非所有参与者都表现出双模优势，但建议在临床合适的情况下，佩戴并试用对侧助听器以利用任何残余听力。
