Fabbri Sara, Caviola Sara, Tang Joey, Zorzi Marco, Butterworth Brian
Department of Psychology , The Brain and Mind Institute, University of Western Ontario, London, Canada.
Q J Exp Psychol (Hove). 2012;65(12):2435-46. doi: 10.1080/17470218.2012.694896. Epub 2012 Jul 16.
The difficulty in processing fractions seems to be related to the interference between the whole-number value of the numerator and the denominator and the real value of the fraction. Here we assess whether the reported problems with symbolic fractions extend to the nonsymbolic domain, by presenting fractions as arrays of black and white dots representing the two operands. Participants were asked to compare a target array with a reference array in two separate tasks using the same stimuli: a numerosity task comparing just the number of white dots in the two arrays; and a proportion task comparing the proportion of black and white dots. The proportion task yielded lower accuracy and slower response, confirming that even with nonsymbolic stimuli accessing proportional information is relatively difficult. However, using a congruity manipulation in which the greater numerosity of white dots could co-occur with a lower proportion of them, and vice versa, it was found that both task-irrelevant dimensions would interfere with the task-relevant dimension suggesting that both numerosity and proportion information was automatically accessed. The results indicate that the magnitude of fractions can be automatically and holistically processed in the nonsymbolic domain.
处理分数的困难似乎与分子和分母的整数值与分数实际值之间的干扰有关。在此，我们通过将分数呈现为代表两个操作数的黑白点阵列，来评估所报告的符号分数问题是否扩展到非符号领域。在两项单独任务中，要求参与者使用相同的刺激物将目标阵列与参考阵列进行比较：一项数量任务，仅比较两个阵列中白点的数量；以及一项比例任务，比较黑白点的比例。比例任务的准确性较低且反应较慢，这证实了即使对于非符号刺激，获取比例信息也相对困难。然而，通过一种一致性操作，即白点数量较多时其比例可能较低，反之亦然，发现两个与任务无关的维度都会干扰与任务相关的维度，这表明数量和比例信息都会被自动获取。结果表明，分数的大小在非符号领域可以被自动且整体地处理。
