Researchers have hypothesized that in order to accommodate variability in how talkers produce their speech sounds, listeners must perform a process of talker normalization. Consistent with this proposal, several studies have shown that spoken word recognition is slowed when speech is produced by multiple talkers compared with when all speech is produced by one talker (a multitalker processing cost). Nusbaum and colleagues have argued that talker normalization is modulated by attention (e.g., Nusbaum & Morin, 1992, Speech Perception, Production and Linguistic Structure, pp. 113–134). Some of the strongest evidence for this claim is from a speeded monitoring study where a group of participants who expected to hear two talkers showed a multitalker processing cost, but a separate group who expected one talker did not (Magnuson & Nusbaum, 2007, Journal of Experimental Psychology, 33[2], 391–409). In that study, however, the sample size was small and the crucial interaction was not significant. In this registered report, we present the results of a well-powered attempt to replicate those findings. In contrast to the previous study, we did not observe multitalker processing costs in either of our groups. To rule out the possibility that the null result was due to task constraints, we conducted a second experiment using a speeded classification task. As in Experiment 1, we found no influence of expectations on talker normalization, with no multitalker processing cost observed in either group. Our data suggest that the previous findings of Magnuson and Nusbaum (2007) be regarded with skepticism and that talker normalization may not be permeable to high-level expectations.

研究人员假设，为了适应说话者发出语音方式的可变性，听众必须执行说话者标准化过程。与这一建议一致的是，一些研究表明，与所有语音均由一个讲话者产生时相比，当多个讲话者产生语音时，口语单词识别速度会变慢（多讲话者处理成本）。 Nusbaum 及其同事认为，说话者标准化是由注意力调节的（例如，Nusbaum & Morin, 1992, Speech Perception, Production and Linguistic Structure, pp. 113–134）。这一说法的一些最有力的证据来自一项快速监控研究，其中一组预期听到两个讲话者的参与者显示出多讲话者处理成本，但预期一个讲话者的另一组参与者却没有这样做（Magnuson＆Nusbaum，2007， Journal of 2007）实验心理学， 33 [2], 391–409）。然而，在那项研究中，样本量很小，关键的相互作用并不显着。在这份注册报告中，我们展示了复制这些发现的有力尝试的结果。与之前的研究相比，我们没有观察到我们两个组中的多说话者处理成本。为了排除由于任务限制而导致无效结果的可能性，我们使用快速分类任务进行了第二次实验。与实验 1 一样，我们发现期望对说话者标准化没有影响，在两组中都没有观察到多说话者处理成本。我们的数据表明，Magnuson 和 Nusbaum（2007）之前的发现值得怀疑，并且谈话者正常化可能无法满足高层期望。