Nygaard L C, Sommers M S, Pisoni D B
Department of Psychology, Indiana University, Bloomington 47405, USA.
Percept Psychophys. 1995 Oct;57(7):989-1001. doi: 10.3758/bf03205458.
A series of experiments was conducted to investigate the effects of stimulus variability on the memory representations for spoken words. A serial recall task was used to study the effects of changes in speaking rate, talker variability, and overall amplitude on the initial encoding, rehearsal, and recall of lists of spoken words. Interstimulus interval (ISI) was manipulated to determine the time course and nature of processing. The results indicated that at short ISIs, variations in both talker and speaking rate imposed a processing cost that was reflected in poorer serial recall for the primary portion of word lists. At longer ISIs, however, variation in talker characteristics resulted in improved recall in initial list positions, whereas variation in speaking rate had no effect on recall performance. Amplitude variability had no effect on serial recall across all ISIs. Taken together, these results suggest that encoding of stimulus dimensions such as talker characteristics, speaking rate, and overall amplitude may be the result of distinct perceptual operations. The effects of these sources of stimulus variability in speech are discussed with regard to perceptual saliency, processing demands, and memory representation for spoken words.
进行了一系列实验来研究刺激变异性对口语单词记忆表征的影响。采用系列回忆任务来研究语速变化、说话者变异性和总体幅度对口语单词列表的初始编码、复述和回忆的影响。通过操纵刺激间隔（ISI）来确定加工的时间进程和性质。结果表明，在短ISI时，说话者和语速的变化都会带来加工成本，这反映在单词列表主要部分的系列回忆较差。然而，在较长ISI时，说话者特征的变化会导致初始列表位置的回忆改善，而语速变化对回忆表现没有影响。幅度变异性在所有ISI下对系列回忆均无影响。综合来看，这些结果表明，诸如说话者特征、语速和总体幅度等刺激维度的编码可能是不同感知操作的结果。本文讨论了语音中这些刺激变异性来源在感知显著性、加工需求和口语单词记忆表征方面的影响。
