Recent studies have reported evidence that listeners' brains process meaning differently in speech with an in-group as compared to an out-group accent. However, among studies that have used electroencephalography (EEG) to examine neural correlates of semantic processing of speech in different accents, the details of findings are often in conflict, potentially reflecting critical variations in experimental design and/or data analysis parameters. To determine which of these factors might be driving inconsistencies in results across studies, we systematically investigate how analysis parameter sets from several of these studies impact results obtained from our own EEG data set. Data were collected from forty-nine monolingual North American English listeners in an event-related potential (ERP) paradigm as they listened to semantically congruent and incongruent sentences spoken in an American accent and an Indian accent. Several key effects of in-group as compared to out-group accent were robust across the range of parameters found in the literature, including more negative scalp-wide responses to incongruence in the N400 range, more positive posterior responses to congruence in the N400 range, and more positive posterior responses to incongruence in the P600 range. These findings, however, are not fully consistent with the reported observations of the studies whose parameters we used, indicating variation in experimental design may be at play. Other reported effects only emerged under a subset of the analytical parameters tested, suggesting that analytical parameters also drive differences. We hope this spurs discussion of analytical parameters and investigation of the contributions of individual study design variables in this growing field.

最近的研究报告了证据表明，与组外口音相比，听者的大脑在使用组内口音的语音中处理意义不同。然而，在使用脑电图 (EEG) 来检查不同口音语音语义处理的神经相关性的研究中，发现的细节往往存在冲突，这可能反映了实验设计和/或数据分析参数的关键变化。为了确定这些因素中的哪些可能导致研究结果不一致，我们系统地调查了其中几项研究的分析参数集如何影响从我们自己的 EEG 数据集获得的结果。数据是从 49 名单语北美英语听众在事件相关电位 (ERP) 范式中收集的，因为他们在听美国口音和印度口音的语义一致和不一致的句子时。与组外口音相比，组内口音的几个关键影响在文献中发现的参数范围内是稳健的，包括对 N400 范围内不一致的更负面的全头皮反应，对 N400 范围内一致的更积极的后验反应，以及对 P600 范围内不一致的更积极的后验反应。然而，这些发现与我们使用的参数的研究报告的观察结果并不完全一致，表明实验设计的变化可能在起作用。其他报告的影响仅在测试的分析参数的一个子集下出现，这表明分析参数也会导致差异。我们希望这能激发对分析参数的讨论和对单个研究设计变量在这个不断发展的领域中的贡献的调查。