Mattys Sven L, Liss Julie M
Department of Experimental Psychology, University of Bristol, 12A Priory Road, Bristol BS8 1TU, England.
Percept Psychophys. 2008 Oct;70(7):1235-42. doi: 10.3758/PP.70.7.1235.
Much of what we know about spoken-word recognition comes from studies relying on speech stimuli either carefully produced in the laboratory or computer altered. Although such stimuli have allowed key constructs to be highlighted, the extent to which these constructs are operative in the processing of everyday speech is unclear. We argue that studying the recognition of naturally occurring degraded speech, such as that produced by individuals with neurological disease, can improve the external validity of existing spoken-word recognition models. This claim is illustrated in an experiment on the effect of talker-specific (indexical) variations on lexical access. We found that talker specificity effects, wherein words are better recalled if played in the same voice than in a different voice between two consecutive blocks, were greater when the words were spoken by dysarthric than by healthy individuals. The effects were found to relate to the increased processing time caused by the dysarthric stimuli, independently of their reduced intelligibility. This result is consistent with Luce, McLennan, and Charles-Luce's (2003) time-course hypothesis, which posits that reliance on indexical details increases when responses are delayed by suboptimal processing conditions. We conclude by advocating the use of laboratory and naturally occurring degraded speech in tandem and more systematic cross-talks between psycholinguistics and the speech sciences.
我们对口语识别的许多了解都来自于依赖语音刺激的研究，这些语音刺激要么是在实验室中精心制作的，要么是经过计算机处理的。尽管这些刺激能够突出关键结构，但这些结构在日常语音处理中的作用程度尚不清楚。我们认为，研究自然产生的退化语音的识别，比如由神经疾病患者产生的语音，可以提高现有口语识别模型的外部效度。这一观点在一项关于说话者特定（索引性）变化对词汇通达影响的实验中得到了证明。我们发现，说话者特异性效应，即在两个连续的板块中，用相同的声音播放单词比用不同的声音播放单词时，单词的回忆效果更好，在构音障碍患者说出的单词中比在健康个体说出的单词中更明显。结果发现，这些效应与构音障碍刺激导致的处理时间增加有关，而与它们降低的可懂度无关。这一结果与卢斯、麦克伦南和查尔斯 - 卢斯（2003）的时间进程假说一致，该假说认为，当反应因次优处理条件而延迟时，对索引性细节的依赖会增加。我们最后主张将实验室语音和自然产生的退化语音结合使用，并在心理语言学和语音科学之间进行更系统的交流。
