Interactions between unsupervised learning and the degree of spectral mismatch on short-term perceptual adaptation to spectrally shifted speech.
Interactions between unsupervised learning and the degree of spectral mismatch on short-term perceptual adaptation to spectrally shifted speech.
复制标题
无监督学习与频谱不匹配程度之间的相互作用对频谱移位语音的短期感知适应。
DOI：
10.1097/aud.0b013e31819769ac
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发表时间：
2009
期刊：
影响因子：
3.7
通讯作者：
Fu,Qian-Jie
中科院分区：
文献类型：
--
作者：
Li,Tianhao;Galvin3rd,JohnJ;Fu,Qian-Jie
目的：通过日常暴露和/或明确的训练，耳蜗植入体听者能够至少部分适应与植入体设备和语音处理器相关的频谱失配。本研究的总体目标是调查短期无监督学习（即被动适应）和频谱失配的程度在正常听力的听众的适应spectrally shifted vowels.Design：正常听力受试者进行测试，而听声学人工耳蜗植入模拟之间的相互作用。无监督学习是通过在5天内重复测试元音识别来测量的;没有提供反馈或明确的训练。在实验1中，受试者听8通道，正弦波声码语音。压缩频谱包络以模拟16 mm耳蜗植入电极阵列。固定分析频带，压缩频谱包络向基底线性偏移3.6、6或8.3 mm，以模拟电极阵列的不同插入深度，导致轻微、中度或严重的频谱偏移。在实验2中，一半的受试者专门暴露于8或16个通道的严重移位（排他性组），一半的受试者暴露于8通道严重移位语音，16通道严重移位语音和8通道中度移位语音，交替出现在每个测试会话（混合组）。耳蜗中的刺激区域是固定的（范围为16 mm，距离顶点15 mm），并且操纵分析频带以创建频谱偏移条件。为了确定是否增加频谱分辨率将提高适应，受试者被暴露于8或16通道严重移位speech.Results：在实验1中，在适应期结束时，有8通道的语音，频谱匹配，并移动3.6毫米之间没有显着差异。有一个显着的，但不完全，适应6毫米的移位，没有适应的8.3毫米移位。在实验2中，对于混合暴露组，有显着的适应严重移位的语音与8个通道，甚至更大的适应与16个通道。对于独家曝光组，有没有显着的适应严重移位的语音与8或16 channel.Conclusions：这些研究结果表明，听众能够被动地适应频谱移位高达6毫米。对于频谱移位超过6毫米，一些被动适应观察到混合曝光到一个较小的频谱移位，即使在一些低频信息的代价。混合暴露于较小的偏移可能增强了听众对频谱包络细节的访问，而这些细节在只听严重偏移的语音时是不可访问的。结果表明，光谱失配的范围，可以支持被动适应可能比以前报道的更大。通过将听者暴露于与严重失配相结合的相对小的失配，对于严重移位的语音，一定量的被动适应是可能的。
Objectives:Cochlear implant listeners are able to at least partially adapt to the spectral mismatch associated with the implant device and speech processor via daily exposure and/or explicit training. The overall goal of this study was to investigate interactions between short-term unsupervised learning (ie, passive adaptation) and the degree of spectral mismatch in normal-hearing listeners' adaptation to spectrally shifted vowels.Design:Normal-hearing subjects were tested while listening to acoustic cochlear implant simulations. Unsupervised learning was measured by testing vowel recognition repeatedly over a 5 day period; no feedback or explicit training was provided. In experiment 1, subjects listened to 8-channel, sine-wave vocoded speech. The spectral envelope was compressed to simulate a 16 mm cochlear implant electrode array. The analysis bands were fixed and the compressed spectral envelope was linearly shifted toward the base by 3.6, 6, or 8.3 mm to simulate different insertion depths of the electrode array, resulting in a slight, moderate, or severe spectral shift. In experiment 2, half the subjects were exclusively exposed to a severe shift with 8 or 16 channels (exclusive groups), and half the subjects were exposed to 8-channel severely shifted speech, 16-channel severely shifted speech, and 8-channel moderately shifted speech, alternately presented within each test session (mixed group). The region of stimulation in the cochlea was fixed (16 mm in extent and 15 mm from the apex) and the analysis bands were manipulated to create the spectral shift conditions. To determine whether increased spectral resolution would improve adaptation, subjects were exposed to 8-or 16-channel severely shifted speech.Results:In experiment 1, at the end of the adaptation period, there was no significant difference between 8-channel speech that was spectrally matched and that shifted by 3.6 mm. There was a significant, but less-complete, adaptation to the 6 mm shift and no adaptation to the 8.3 mm shift. In experiment 2, for the mixed exposure group, there was significant adaptation to severely shifted speech with 8 channels and even greater adaptation with 16 channels. For the exclusive exposure group, there was no significant adaptation to severely shifted speech with either 8 or 16 channels.Conclusions:These findings suggest that listeners are able to passively adapt to spectral shifts up to 6 mm. For spectral shifts beyond 6 mm, some passive adaptation was observed with mixed exposure to a smaller spectral shift, even at the expense of some low frequency information. Mixed exposure to the smaller shift may have enhanced listeners' access to spectral envelope details that were not accessible when listening exclusively to severely shifted speech. The results suggest that the range of spectral mismatch that can support passive adaptation may be larger than previously reported. Some amount of passive adaptation may be possible with severely shifted speech by exposing listeners to a relatively small mismatch in conjunction with the severe mismatch.