Rush University Medical Center, Communication Disorders and Sciences, Chicago, IL 60612, USA.
Ear Hear. 2011 Jul-Aug;32(4):511-23. doi: 10.1097/AUD.0b013e3182064a87.
Environmental sound perception serves an important ecological function by providing listeners with information about objects and events in their immediate environment. Environmental sounds such as car horns, baby cries, or chirping birds can alert listeners to imminent dangers as well as contribute to one's sense of awareness and well being. Perception of environmental sounds as acoustically and semantically complex stimuli may also involve some factors common to the processing of speech. However, very limited research has investigated the abilities of cochlear implant (CI) patients to identify common environmental sounds, despite patients' general enthusiasm about them. This project (1) investigated the ability of patients with modern-day CIs to perceive environmental sounds, (2) explored associations among speech, environmental sounds, and basic auditory abilities, and (3) examined acoustic factors that might be involved in environmental sound perception.
Seventeen experienced postlingually deafened CI patients participated in the study. Environmental sound perception was assessed with a large-item test composed of 40 sound sources, each represented by four different tokens. The relationship between speech and environmental sound perception and the role of working memory and some basic auditory abilities were examined based on patient performance on a battery of speech tests (HINT, CNC, and individual consonant and vowel tests), tests of basic auditory abilities (audiometric thresholds, gap detection, temporal pattern, and temporal order for tones tests), and a backward digit recall test.
The results indicated substantially reduced ability to identify common environmental sounds in CI patients (45.3%). Except for vowels, all speech test scores significantly correlated with the environmental sound test scores: r = 0.73 for HINT in quiet, r = 0.69 for HINT in noise, r = 0.70 for CNC, r = 0.64 for consonants, and r = 0.48 for vowels. HINT and CNC scores in quiet moderately correlated with the temporal order for tones. However, the correlation between speech and environmental sounds changed little after partialling out the variance due to other variables.
Present findings indicate that environmental sound identification is difficult for CI patients. They further suggest that speech and environmental sounds may overlap considerably in their perceptual processing. Certain spectrotemproral processing abilities are separately associated with speech and environmental sound performance. However, they do not appear to mediate the relationship between speech and environmental sounds in CI patients. Environmental sound rehabilitation may be beneficial to some patients. Environmental sound testing may have potential diagnostic applications, especially with difficult-to-test populations and might also be predictive of speech performance for prelingually deafened patients with cochlear implants.
环境声音感知通过向听众提供其周围环境中物体和事件的信息，从而发挥重要的生态功能。汽车喇叭声、婴儿哭声或鸟鸣声等环境声音可以提醒听众注意即将到来的危险，同时也有助于增强他们的意识和幸福感。对环境声音的感知作为复杂的听觉刺激，可能涉及到一些与言语处理共同的因素。然而，尽管患者普遍对其感兴趣，但针对使用现代人工耳蜗（CI）的患者识别常见环境声音的能力，相关研究非常有限。本项目（1）研究了具有现代 CI 的患者感知环境声音的能力，（2）探讨了言语、环境声音和基本听觉能力之间的关联，（3）检验了可能涉及环境声音感知的声学因素。
17 名成年后失聪的 CI 患者参与了这项研究。使用由 40 个声源组成的大项目测试来评估环境声音感知，每个声源都有四个不同的样本。根据患者在一系列言语测试（HINT、CNC 以及个人辅音和元音测试）、基本听觉能力测试（听阈、间隙检测、音调和音序测试）和数字倒背测试中的表现，考察了言语和环境声音感知之间的关系以及工作记忆和一些基本听觉能力的作用。
结果表明，CI 患者识别常见环境声音的能力明显下降（45.3%）。除了元音，所有言语测试得分均与环境声音测试得分显著相关：安静时 HINT 为 r = 0.73，噪声中 HINT 为 r = 0.69，CNC 为 r = 0.70，辅音为 r = 0.64，元音为 r = 0.48。安静时 HINT 和 CNC 与音调顺序的相关性较强。然而，在将其他变量的方差部分排除后，言语和环境声音之间的相关性变化不大。
目前的研究结果表明，环境声音识别对 CI 患者来说很困难。进一步表明，言语和环境声音在感知处理上可能有很大的重叠。某些特定的频谱时间处理能力与言语和环境声音表现分别相关。然而，它们似乎并没有介导 CI 患者言语和环境声音之间的关系。环境声音康复可能对某些患者有益。环境声音测试可能具有潜在的诊断应用价值，特别是对于难以测试的人群，也可能对使用人工耳蜗的成年后失聪患者的言语表现具有预测作用。
