Effects of the rate of formant-frequency variation on the grouping of formants in speech perception.
Effects of the rate of formant-frequency variation on the grouping of formants in speech perception.
复制标题
共振峰频率变化率对语音感知中共振峰分组的影响。
DOI：
10.1007/s10162-011-0307-y
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Summers RJ
中科院分区：
文献类型：
--
作者：
Summers RJ
言语是如何在感知上与其他言语分离的，人们仍然知之甚少。最近的研究表明，一个外来共振峰损害清晰度的能力取决于其频率的调制，而不是其幅度，轮廓。本研究通过控制共振峰频率的变化率进一步研究了共振峰频率变化对可懂度的影响。目标句子是自然话语的合成三共振峰（F1 + F2 + F3）类似物。知觉组织的探讨提出刺激二分法（F1 + F2C + F3 C; F2 + F3），其中F2C + F3 C构成的F2和F3的竞争对手，听众必须拒绝优化识别。竞争对手来自使用共振峰频率轮廓提取的扩展通道由同一说话者和处理，以改变共振峰频率的变化率，使率比例因子相对于目标句子为0，0.25，0.5，1，2，和4（0 =恒定频率）。竞争对手的振幅轮廓是恒定的，或时间反转和速率调整的频率轮廓平行。增加一个竞争者通常会降低可懂度;这种降低会随着竞争者的速率增加，直到速率至少是目标句子的两倍。两种振幅条件的结果相似，证实了共振峰振幅轮廓不影响跨共振峰分组。研究结果表明，竞争者的功效是不调整的目标句子的速度，最有可能的是，它主要取决于在竞争对手共振峰的频率变化的整体速度。这表明，当隔离并发谈话者的语音，在语音速率的差异可能不是一个重要的线索跨频率分组的共振峰。
How speech is separated perceptually from other speech remains poorly understood. Recent research suggests that the ability of an extraneous formant to impair intelligibility depends on the modulation of its frequency, but not its amplitude, contour. This study further examined the effect of formant-frequency variation on intelligibility by manipulating the rate of formant-frequency change. Target sentences were synthetic three-formant (F1 + F2 + F3) analogues of natural utterances. Perceptual organization was probed by presenting stimuli dichotically (F1 + F2C + F3C; F2 + F3), where F2C + F3C constitute a competitor for F2 and F3 that listeners must reject to optimize recognition. Competitors were derived using formant-frequency contours extracted from extended passages spoken by the same talker and processed to alter the rate of formant-frequency variation, such that rate scale factors relative to the target sentences were 0, 0.25, 0.5, 1, 2, and 4 (0 = constant frequencies). Competitor amplitude contours were either constant, or time-reversed and rate-adjusted in parallel with the frequency contour. Adding a competitor typically reduced intelligibility; this reduction increased with competitor rate until the rate was at least twice that of the target sentences. Similarity in the results for the two amplitude conditions confirmed that formant amplitude contours do not influence across-formant grouping. The findings indicate that competitor efficacy is not tuned to the rate of the target sentences; most probably, it depends primarily on the overall rate of frequency variation in the competitor formants. This suggests that, when segregating the speech of concurrent talkers, differences in speech rate may not be a significant cue for across-frequency grouping of formants.