时域和频域信息对汉语普通话声调识别的影响

目的通过探讨时域和频域信息对听力正常人声调识别的影响,试图为人工耳蜗汉语言语编码策略的编制提供理论依据.方法共有13名听力正常人参加本次研究,均以普通话作为日常交流方式.测试材料使用美国Ohio大学提供的声调识别测试系统.测试系统包含10组测试词.每组测试词的声、韵母相同而声调不同.将上述测试词录制成原始声音文件.采用声码器技术处理录制的原始声音.将决定时域信息的低通滤波器的截止频率设为1、2、4、8、16、32、64、128、256和512 Hz,共10种;将决定频域信息的通道数设为1、2、4、6、8、12、16和20,共8种.经不同的排列组合,共产生6400个处理后的声音文件.测试在标准隔声室内进行.测试声音通过扬声器发出,强度为65 dB SPL.声音的发出和成绩的记录均由Matlab软件自动完成.结果听力正常人的声调识别得分随着低通滤波的截止频率和通道数的增加而增加.当低通滤波的截止频率在2 Hz以下时,是否增加通道数对声调识别得分基本没有影响.当通道数在2以下时,是否增加低通滤波的截止频率对声调识别得分基本没有影响.结论听力正常人的声调识别与时域和频域信息均相关.时域信息和频域信息在听力正常人的声调识别中的作用是协同的.     

言语识别中的时域及频域信息

本文对言语识别中的声学要素从时域和频域的角度进行探讨，旨在为人工耳蜗编码策略的改善提供理论依据。声码器技术被用于一系列的实验以确定时域和频域信息对言语识别和汉语四声识别的相互作用。频域信息是由声码器中的频道数来决定，而时域信息则是由声码器的低通滤波器的截止频率来决定。听力正常成人参加了各项感知试验。结果表明，时域和频域信息都对音素识别很重要。在安静环境下。辅音和元音识别率分别在8和12频道及16Hz和4Hz的低通截止频率时达到平台成绩。在噪声环境下，元音识别受益于增高的频道数。汉语四声的识别需要256Hz的低通截止频率才达到平台成绩，这一频率比英语音素识别所需的时域信息高得多。声调识别率在本研究中最高频道数12时仍未见饱和。为了研究细微结构和时域包络对四声识别的相对重要性．我们用声嵌合技术将不同声调信号的时域包络和细微结构进行对换。感知实验结果表明，声调识别主要取决于细微结构，这一点与音乐感知的结果类似，而不象言语识别，后者主要依赖于时域包络信息。因此，增加人工耳蜗系统中有效的频道数将有助于尤其是噪声环境下的言语识别。将人工耳蜗刺激中提供更多的细微结构信息可能会提高患者声调识别的成绩。     

共振峰信息在汉语声调感知中的作用

目的探讨言语频域共振峰信息在汉语普通话声调识别中的作用。方法采用线性预测编码（linearprediction coding,LPC）技术将单音节字的频域包络（即共振峰信息）与精细结构（即基频谐波信息）分离,合成128个只具有频域包络信息的＂单音节字＂。使用这些＂单音节字＂测试20例听力正常受试者的声调感知能力。结果听力正常受试者依靠共振峰信息识别三声的正确率为69%,识别二声的正确率为42%,识别一声和四声的能力均低于机会值（25%）,声调的平均识别率为36%。只依靠共振峰信息,三声与二声的识别容易混淆,一声与四声较易误识别成二声与三声。结论共振峰信息（尤其是第一共振峰）可以为声调识别提供一些线索,但不起主要作用。     

汉语声调对感音神经性听力损失患者噪声下语句识别的作用

目的 探讨言语声调信息对于感音神经性听力损失(sensorineural hearing loss,SNHL)患者噪声下言语识别的作用.方法 选取听力正常者10例(平均22.5±1.02岁)、S N H L患者38例(平均36.92±12.38岁,轻度听力损失10例,中度听力损失18例,重度听力损失10例)、听神经病谱...     

听力正常人噪声下汉语普通话声调识别成绩-强度函数的研究

目的　获得噪声下声调识别测试（t o n e identification in noise test,TINT）材料的听力正常人识别成绩-强度（performance-intensity,PI）函数。方法　利用已确立的TINT测试材料对16名年龄在21～28岁、以普通话作为日常交流语言的听力正常人进行声调识别测试,使用SPSS17.0统计软件对结果进行分析。结果　听力正常成人PI 斜率分别为8.6%/dB（男声）、7.3%/dB（女声）（P =0.11）;听力正常成人PI函数信噪比50阈值分别为男声（-12.9±0.8）dB、女声（-13.6±1）dB（t =2.7,P =0.016）;声调类型和播音者性别对PI曲线阈值的影响即存在交互作用（F =11.7,P＜0.001)、亦存在独立作用（声调类型：F =83.7,P＜0.001;播音员性别：F =31.0,P＜0.05),其中听力正常人一声和四声识别阈值明显低于二声和三声识别阈值。结论　本研究初步建立基于TINT测试材料的听力正常人噪声下声调识别PI函 数,以期为临床工作和科学研究提供一个可选择的测量工具。     

植入人工耳蜗与配戴助听器儿童背景噪声下的声调识别

目的 探讨植入人工耳蜗与配戴助听器儿童在声调识别方面是否存在差异,分析背景噪声对听障儿童声调识别的影响.了解在噪声环境中听障儿童声调识别的特点.方法 采用2X4两因素混合实验设计,比较植入人工耳蜗与配戴助听器儿童在不同信噪比条件下(SNR=+12,+6,0 dB)的声调识别能力;采用单因素方差分析,比较不同声调组合识别对听障儿童的难易程度.结果 ①在重建或补偿听阈相似时,植入人工耳蜗与配戴助听器儿童声调识别能力的差异不显著;②在不同信噪比条件下,两组儿童声调识别能力的差异极其显著;③两组儿童均最易分辨一声与四声的差异,最难分辨二声与三声的差异.结论 只要重建或补偿听阈在最适范围,听障儿童便具有一定的声调识别能力,但噪声会对其产生极大的影响.     

听觉和视觉线索在人工耳蜗植入儿童感知汉语声调中的作用

目的 考察在安静环境和噪声环境下,提供视觉线索是否能帮助人工耳蜗植入儿童准确辨识汉语声调。方法 招募80名学龄前人工耳蜗植入儿童（研究组）和50名健听儿童（对照组）,在安静及噪声环境下,通过听录音或看视频并选择与之对应的卡通图片方式,考察儿童在依靠听觉单一线索和依靠听、视觉双线索条件下声调的辨识情况。结果 在安静及噪声环境下,视觉线索会帮助人工耳蜗植入儿童更好地辨认汉语声调,但效果取决于具体声调：在安静环境下,二声在音视频条件下识别率显著高于仅音频条件（P<0.05）;在噪声环境下,一声和三声在音视频条件下识别率显著高于仅音频条件（P<0.05）。结论人工耳蜗植入儿童可借助视觉线索（即说话人的面部表情）更准确地辨识汉语声调,为言语康复中声调的感知训练提供启示。     

诺尔康人工耳蜗植人者的声调识别与生活质量评价

目的：评估诺尔康人工耳蜗植入者对普通话的声调识别能力和术后生活质量。方法：49例植入诺尔康人工耳蜗1年的受试者,使用课题组前期编制的声调识别测试软件,评估植入者的声调识别能力;使用Ni-jmegen人工耳蜗植入量表（NCIQ）,评估植人者术后生活质量。结果：①安静条件下声调识别率平均为67．26％,全部高于机会水平;②噪声条件下声调识别率平均为51．92％,除2例植入者的声调识别率低于机会水平外,其余均高于机会水平;③声调识别混淆矩阵结果显示,三声为较容易辨别的声调;④术后NCIQ总分及基本声音感知、高级声音感知、言语能力、自信心、活动能力和交流能力均获得改善,分别为55．4、72．4、54．0、63．4、50．7、47．3和44．7分。结论：诺尔康人工耳蜗植入者术后具有声调识别能力并可获得生活质量的改善。     

感音神经性听力损失患者不同噪声模式下的言语识别能力研究

目的　研究不同噪声模式对听力正常者和感音神经性听力损失者言语识别能力的影响。方法　通过MATLAB软件播放儿童版汉语普通话噪声下言语测试句表,测试25名听力正常受试者和20例感音神经性聋受试者分别在安静环境、语谱噪声、双人语噪声下的言语识别能力,分析两者在安静和两种噪声模式下对语句感知能力的差异。结果　随信噪比降低,听力正常者在语谱噪声下言语识别率低于双人语噪声,但差异无统计学意义（P＞0.05）。感音神经性听力损失者在信噪比+5 dB时,双人语噪声下言语识别率低于语谱噪声,且差异有统计学意义（P＜0.05）。结论 　两种噪声模式对比,听力正常者在双人语噪声下言语识别率更高,感音神经性听力损失者在语谱噪声下言语识别率更高。     

Relative Contributions of Temporal Envelope and Fine Structure Cues to Lexical Tone Recognition in Hearing-Impaired Listeners

It has been reported that normal-hearing Chinese speakers base their lexical tone recognition on fine structure regardless of temporal envelope cues. However, a few psychoacoustic and perceptual studies have demonstrated that listeners with sensorineural hearing impairment may have an impaired ability to use fine structure information, whereas their ability to use temporal envelope information is close to normal. The purpose of this study is to investigate the relative contributions of temporal envelope and fine structure cues to lexical tone recognition in normal-hearing and hearing-impaired native Mandarin Chinese speakers. Twenty-two normal-hearing subjects and 31 subjects with various degrees of sensorineural hearing loss participated in the study. Sixteen sets of Mandarin monosyllables with four tone patterns for each were processed through a “chimeric synthesizer” in which temporal envelope from a monosyllabic word of one tone was paired with fine structure from the same monosyllable of other tones. The chimeric tokens were generated in the three channel conditions (4, 8, and 16 channels). Results showed that differences in tone responses among the three channel conditions were minor. On average, 90.9%, 70.9%, 57.5%, and 38.2% of tone responses were consistent with fine structure for normal-hearing, moderate, moderate to severe, and severely hearing-impaired groups respectively, whereas 6.8%, 21.1%, 31.4%, and 44.7% of tone responses were consistent with temporal envelope cues for the above-mentioned groups. Tone responses that were consistent neither with temporal envelope nor fine structure had averages of 2.3%, 8.0%, 11.1%, and 17.1% for the above-mentioned groups of subjects. Pure-tone average thresholds were negatively correlated with tone responses that were consistent with fine structure, but were positively correlated with tone responses that were based on the temporal envelope cues. Consistent with the idea that the spectral resolvability is responsible for fine structure coding, these results demonstrated that, as hearing loss becomes more severe, lexical tone recognition relies increasingly on temporal envelope rather than fine structure cues due to the widened auditory filters.     

Effects of Temporal Fine Structure on the Lateralization of Speech and on Speech Understanding in Noise

This study evaluated the role of temporal fine structure in the lateralization and understanding of speech in six normal-hearing listeners. Interaural time differences (ITDs) were introduced to invoke lateralization. Speech reception thresholds (SRTs) were evaluated in backgrounds of two-talker babble and speech-shaped noise. Two-syllable words with ITDs of 0 and 700 μs were used as targets. A vocoder technique, which systematically randomized fine structure, was used to evaluate the effects of fine structure on these tasks. Randomization of temporal fine structure was found to significantly reduce the ability of normal-hearing listeners to lateralize words, although for many listeners, good lateralization performance was achieved with as much as 80% fine-structure randomization. Most listeners demonstrated some rudimentary ability to lateralize with 100% fine-structure randomization. When ITDs were 0 μs, randomization of fine structure had a much greater effect on SRT in two-talker babble than in speech-shaped noise. Binaural advantages were also observed. In steady noise, the difference in SRT between words with 0- vs 700-μs ITDs was, on average, 6 dB with no fine-structure randomization and 2 dB with 100% fine-structure randomization. In two-talker babble this difference was 1.9 dB and, for most listeners, showed little effect of the degree of fine-structure randomization. These results suggest that (1) improved delivery of temporal fine structure would improve speech understanding in noise for implant recipients, (2) bilateral implant recipients might benefit from temporal envelope ITDs, and (3) improved delivery of temporal information could improve binaural benefits.     

Implications of Within-Fiber Temporal Coding for Perceptual Studies of F0 Discrimination and Discrimination of Harmonic and Inharmonic Tone Complexes

Recent psychophysical studies suggest that normal-hearing (NH) listeners can use acoustic temporal-fine-structure (TFS) cues for accurately discriminating shifts in the fundamental frequency (F0) of complex tones, or equal shifts in all component frequencies, even when the components are peripherally unresolved. The present study quantified both envelope (ENV) and TFS cues in single auditory-nerve (AN) fiber responses (henceforth referred to as neural ENV and TFS cues) from NH chinchillas in response to harmonic and inharmonic complex tones similar to those used in recent psychophysical studies. The lowest component in the tone complex (i.e., harmonic rank N) was systematically varied from 2 to 20 to produce various resolvability conditions in chinchillas (partially resolved to completely unresolved). Neural responses to different pairs of TEST (F0 or frequency shifted) and standard or reference (REF) stimuli were used to compute shuffled cross-correlograms, from which cross-correlation coefficients representing the degree of similarity between responses were derived separately for TFS and ENV. For a given F0 shift, the dissimilarity (TEST vs. REF) was greater for neural TFS than ENV. However, this difference was stimulus-based; the sensitivities of the neural TFS and ENV metrics were equivalent for equal absolute shifts of their relevant frequencies (center component and F0, respectively). For the F0-discrimination task, both ENV and TFS cues were available and could in principle be used for task performance. However, in contrast to human performance, neural TFS cues quantified with our cross-correlation coefficients were unaffected by phase randomization, suggesting that F0 discrimination for unresolved harmonics does not depend solely on TFS cues. For the frequency-shift (harmonic-versus-inharmonic) discrimination task, neural ENV cues were not available. Neural TFS cues were available and could in principle support performance in this task; however, in contrast to human-listeners’ performance, these TFS cues showed no dependence on N. We conclude that while AN-fiber responses contain TFS-related cues, which can in principle be used to discriminate changes in F0 or equal shifts in component frequencies of peripherally unresolved harmonics, performance in these two psychophysical tasks appears to be limited by other factors (e.g., central processing noise).     

The Role of Temporal Fine Structure Processing in Pitch Perception,Masking, and Speech Perception for Normal-Hearing and Hearing-Impaired People

Complex broadband sounds are decomposed by the auditory filters into a series of relatively narrowband signals, each of which can be considered as a slowly varying envelope (E) superimposed on a more rapid temporal fine structure (TFS). Both E and TFS information are represented in the timing of neural discharges, although TFS information as defined here depends on phase locking to individual cycles of the stimulus waveform. This paper reviews the role played by TFS in masking, pitch perception, and speech perception and concludes that cues derived from TFS play an important role for all three. TFS may be especially important for the ability to "listen in the dips" of fluctuating background sounds when detecting nonspeech and speech signals. Evidence is reviewed suggesting that cochlear hearing loss reduces the ability to use TFS cues. The perceptual consequences of this, and reasons why it may happen, are discussed.     

听障儿童双字调三声发音的难度分析

目的：分析听障儿童双字调中三声的发音情况,探讨其发音的难度层次,为听障儿童三声的发音训练提供参考依据。方法以8种双字调中三声的组合为基础,测试120名3～5岁听障儿童的三声发音情况。结果听障儿童双字调中三声不同组合形式的发音难度差异有显著统计学意义（P＜0.01）,从易到难依次为3-1和3-4组合;3-2、3-3（前）和3-3（后）组合;2-3、1-3和4-3组合。结论听障儿童双字调三声的发音难度可划分为3个层次,在训练时应遵循难度层次依次进行,以提高康复效率。     

Spectral and Temporal Envelope Cues for Human and Automatic Speech Recognition in Noise

Journal of the Association for Research in Otolaryngology - Acoustic features of speech include various spectral and temporal cues. It is known that temporal envelope plays a critical role for...     

The effects of age on temporal fine structure sensitivity in monaural and binaural conditions

Abstract

Objective: To extend the study of Hopkins and Moore (2011) by examining the effect of age in the medium age range on sensitivity to temporal fine structure (TFS), which is assumed to be represented in the patterns of phase locking in the auditory nerve. Design: Monaural TFS sensitivity was assessed using the TFS1 test (Moore & Sek, 2009) at centre frequencies of 850 and 2000 Hz, and binaural TFS sensitivity was assessed using the TFS-LF test (Hopkins & Moore, 2010a) at centre frequencies of 500 and 850 Hz, using a sensation level of 30 dB. Study sample: Thirty-five newly recruited normal-hearing subjects (thresholds better than 20 dB HL from 250 to 6000 Hz) were tested. Their ages ranged from 22 to 61 years. Results: There was a significant correlation between age and TFS sensitivity at all frequencies for both TFS tests. For the single centre frequency (850 Hz) that was used for both tests, scores for the two tests were modestly but significantly correlated. Conclusions: Sensitivity to TFS decreases with increasing age. The monaural and binaural TFS tests appear to reflect at least somewhat distinct auditory processes.     

Development of a fast method for determining sensitivity to temporal fine structure

Recent evidence suggests that sensitivity to the temporal fine structure (TFS) of sounds is adversely affected by cochlear hearing loss. This may partly explain the difficulties experienced by people with cochlear hearing loss in understanding speech when background sounds, especially fluctuating backgrounds, are present. We describe a test for assessing sensitivity to TFS. The test can be run using any PC with a sound card. The test involves discrimination of a harmonic complex tone (H), with a fundamental frequency F0, from a tone in which all harmonics are shifted upwards by the same amount in Hertz, resulting in an inharmonic tone (I). The phases of the components are selected randomly for every stimulus. Both tones have an envelope repetition rate equal to F0, but the tones differ in their TFS. To prevent discrimination based on spectral cues, all tones are passed through a fixed bandpass filter, usually centred at 11F0. A background noise is used to mask combination tones. The results show that, for normal-hearing subjects, learning effects are small, and the effect of the level of testing is also small. The test provides a simple, quick, and robust way to measure sensitivity to TFS.     

Development of a fast method for measuring sensitivity to temporal fine structure information at low frequencies

Abstract

Recent work suggests that hearing-impaired subjects are relatively insensitive to temporal fine structure (TFS) information, but that sensitivity among subjects varies considerably. developed a fast and easy to administer test of sensitivity to TFS, but it can only be used at medium to high frequencies. Here we describe a binaural method that can be used at lower frequencies. An adaptive two-alternative forced-choice task was used. Each interval contained four tones with frequency f; in one interval all tones were diotic, and in the other tones one and three were diotic while tones two and four had an interaural phase shift, Δ?. The task was to identify the interval with the phase-shifted tones. For normal-hearing subjects, the effects of sensation level and training on performance were small, and the test could be performed reliably for f = 250, 500, and 750 Hz.

Sumario

Varios trabajos recientes sugieren que las personas con impedimentos auditivos son relativamente no sensibles a la información temporal de estructura fina (TFS), pero la sensibilidad entre sujetos varía considerablemente. desarrollaron una prueba rápida de sensibilidad TFS fácil de administrar, pero solo puede usarse en las frecuencias medias y altas. Describimos aquí un método binaural que puede usarse en frecuencias graves. Se usó una tarea adaptativa para la selección forzada de dos alternativas. Cada intervalo contenía cuatro tonos con frecuencia f; en un intervalo, todos los tonos fueron dicóticos y con los otros tonos, uno y tres, fueron dicóticos mientras que los tonos dos y cuatro, tuvieron un cambio de fase interaural Δ?. La tarea fue identificar el intervalo con los tonos que tenían cambio de fase. En los sujetos con audición normal, fueron pequeños los efectos del nivel de sensación y el entrenamiento en el desempeño, y la prueba podría ser realizada confiablemente para f =250, 500 y 750 Hz.     

Perception of temporal fine-structure cues in speech with minimal envelope cues for listeners with mild-to-moderate hearing loss

Abstract

The contribution of temporal fine-structure (TFS) cues to consonant identification was compared for seven young adults with normal hearing and five young adults with mild-to-moderate hearing loss and flat, high- or low-frequency gently sloping audiograms. Nonsense syllables were degraded using two schemes (PM: phase modulation; FM: frequency modulation) designed to remove temporal envelope (E) cues while preserving TFS cues in 16 0.35-octave-wide frequency bands spanning the range of 80 to 8020 Hz. For both schemes, hearing-impaired listeners performed significantly above chance level (PM: 36%; FM: 31%; chance level: 6.25%), but more poorly than normal-hearing listeners (PM: 80%; FM: 65%). Three hearing-impaired listeners showed normal or near-normal reception of nasality information. These results indicate that for mild to moderate levels of hearing loss, cochlear damage reduces but does not abolish the ability to use the TFS cues of speech. The deficits observed for both schemes in hearing-impaired listeners suggest involvement of factors other than only poor reconstruction of temporal envelope from temporal fine structure.

Sumario

Se comparó la contribución de claves temporales de estructura fina (TFS) para la identificación de consonantes en seis adultos jóvenes con audición normal y cinco adultos jóvenes con hipoacusia superficial a moderada con audiogramas planos, o con caídas suaves en graves o en agudos. Se degradaron sílabas sin sentido utilizando dos esquemas (PM: modulación de fase; FM: modulación de frecuencia) diseñados para remover las claves de envoltura temporal (E) mientras que se preservaron las caves TFS en 16 bandas con anchos de frecuencia de 0.35 de octava, espaciando el rango de 80 a 8020Hz. Para ambos esquemas, los oyentes con hipoacusia se desempeñaron significativamente por encima del nivel de azar (PM: 36%; FM: 31%; Nivel de azar : 6.5%) pero mucho menos que los normoyentes (PM: 80%; FM: 65%). Tres sujetos con hipoacusia mostraron una recepción normal o casi normal de la información de nasalidad. Estos resultados indican que para la hipoacusia superficial a moderada el daño coclear reduce pero no cancela la habilidad para usar las claves TFS del lenguaje. Los déficits observados para ambos esquemas en sujetos hipoacúsicos sugiere una participación de factores diferentes a la pobre reconstrucción de la envoltura temporal de la estructura fina.