Department of Psychology and the Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva, Israel.
Cortex. 2013 May;49(5):1352-62. doi: 10.1016/j.cortex.2012.03.019. Epub 2012 Apr 10.
Number-space synesthetes visualize numbers in specific spatial configurations. Their spatial-numerical perceptions are assumed to be automatic in nature and have been found to affect performance in various numerical tasks. The current study tested whether synesthetic number-space associations can modulate the well-established Size Congruency Effect (SiCE), which is considered to be an indication for the automaticity of numerical processing. Two groups, number-space synesthetes and matched controls, were tested on a numerical Stroop task (Henik and Tzelgov, 1982). In separate blocks, participants were presented with two digits and asked to make comparative judgments regarding either numerical values (numerical comparison) or physical size (physical comparison). Both dimensions were manipulated orthogonally, creating three congruency levels: congruent (e.g., 2 7), incongruent (e.g., 2 7) and neutral (e.g., 2 2 and 2 7 for physical and numerical blocks, respectively). For the numerical block, both synesthetes and controls showed the classic SiCE, indicating similar automatic processing of physical magnitude. However, in the physical block, synesthetes showed a lack of automatic numerical magnitude processing when the numbers to be compared were presented incompatibly with their relative position on the synesthetic number-form. This finding strongly suggests that synesthetes' number-space perceptions affect their ability to automatically process the semantic meaning of numerals. The involvement of space in automatic magnitude processing for number-space synesthetes and non-synesthetes is discussed.
联觉者会将数字以特定的空间形式进行可视化。他们的空间-数字感知被认为是自动的，并且已经在各种数字任务中发现会影响表现。当前的研究测试了联觉的数字-空间联想是否可以调节已经确立的大小一致效应（Size Congruency Effect，SiCE），这被认为是数字处理自动性的一个指标。两组被试，联觉者和匹配的对照组，在数字斯特鲁普任务（Henik 和 Tzelgov，1982）中接受测试。在单独的块中，参与者会看到两个数字，并被要求对数值（数值比较）或物理大小（物理比较）进行比较判断。两个维度都是正交操纵的，创建了三个一致性水平：一致（例如，27）、不一致（例如，27）和中性（例如，分别用于物理和数值块的 22 和 27）。对于数值块，联觉者和对照组都表现出经典的 SiCE，表明对物理大小的自动处理相似。然而，在物理块中，当要比较的数字与联觉数字形式的相对位置不兼容时，联觉者表现出缺乏自动数字大小处理的能力。这一发现强烈表明，联觉者的数字-空间感知会影响他们自动处理数字语义的能力。讨论了联觉者和非联觉者在自动大小处理中空间的参与。
