Dickson Danielle S, Federmeier Kara D
Department of Biology, University of Texas, San Antonio, 1 UTSA Circle, San Antonio, TX 78249, USA; Department of Psychology, University of Illinois, Urbana-Champaign, 603 E. Daniel St., Champaign, IL 61820, USA.
Department of Psychology, University of Illinois, Urbana-Champaign, 603 E. Daniel St., Champaign, IL 61820, USA; Program in Neuroscience, University of Illinois, Urbana-Champaign, USA; Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana-Champaign, USA.
Brain Res. 2017 May 1;1662:46-56. doi: 10.1016/j.brainres.2017.02.019. Epub 2017 Feb 22.
Arithmetic expressions, like verbal sentences, incrementally lead readers to anticipate potential appropriate completions. Existing work in the language domain has helped us understand how the two hemispheres differently participate in and contribute to the cognitive process of sentence reading, but comparatively little work has been done with mathematical equation processing. In this study, we address this gap by examining the ERP response to provided answers to simple multiplication problems, which varied both in levels of correctness (given an equation context) and in visual field of presentation (joint attention in central presentation, or biased processing to the left or right hemisphere through contralateral visual field presentation). When answers were presented to any of the visual fields (hemispheres), there was an effect of correctness prior to the traditional N400 timewindow, which we interpret as a P300 in response to a detected target item (the correct answer). In addition to this response, equation answers also elicited a late positive complex (LPC) for incorrect answers. Notably, this LPC effect was most prominent in the left visual field (right hemisphere), and it was also sensitive to the confusability of the wrong answer - incorrect answers that were closely related to the correct answer elicited a smaller LPC. This suggests a special, prolonged role for the right hemisphere during answer evaluation.
算术表达式与文字句子一样，会逐步引导读者预期可能的合适完成形式。语言领域的现有研究有助于我们理解两个半球如何以不同方式参与句子阅读的认知过程并为之做出贡献，但在数学方程处理方面的相关研究较少。在本研究中，我们通过检查对简单乘法问题所提供答案的事件相关电位（ERP）反应来填补这一空白，这些答案在正确性水平（给定方程背景）和呈现视野（中央呈现时的共同注意，或通过对侧视野呈现向左侧或右侧半球进行偏向处理）方面均有所不同。当向任何视野（半球）呈现答案时，在传统的N400时间窗口之前就存在正确性效应，我们将其解释为对检测到的目标项目（正确答案）的P300反应。除了这种反应外，方程答案对错误答案还引发了晚期正复合波（LPC）。值得注意的是，这种LPC效应在左视野（右半球）最为显著，并且它也对错答案的可混淆性敏感——与正确答案密切相关的错误答案引发的LPC较小。这表明右半球在答案评估过程中具有特殊的、持续较长时间的作用。
