Abstract:

Developmental dyscalculia (DD) is a pervasive disorder that impairs number processing and arithmetic skills. Although previous research has examined both general cognitive functions and specific numerical deficits, the core impairment underlying dyscalculia remains uncertain. This study aimed to evaluate two hypothesized contributors: specific numerical deficits and spatial abilities. We compared 31 children with DD and 31 age- and gender-matched typically developing children on a series of numerical and spatial tasks. The results revealed no significant group differences in accuracy on the non-symbolic magnitude comparison task or the small exact enumeration task; however, children with DD responded significantly more slowly. On the Arabic numeral comparison and large number estimation tasks, there were no significant differences in either accuracy or response time. On the horizontal plane task, children with DD showed marginally longer response times than controls (p = 0.068). These findings support the hypothesis of a deficient approximate quantitative representation system in dyscalculia and suggest that external static spatial capacity may warrant further investigation.

Key words: developmental dyscalculia, cognitive deficits, approximate quantitative representation, precise quantitative representation, spatial capacity

摘要：

通过探讨发展性计算障碍儿童的数量认知加工缺陷和空间亚能力特点，进一步明确发展性计算障碍的核心缺陷。采取整群取样方式对赣州市两所小学共1501名三至六年级儿童进行筛查，最终随机选取31名计算障碍儿童，以及31名正常发展儿童作为对照组。两组儿童均参与一系列的基本数量加工和空间能力测试。结果显示：(1)在非符号数量比较任务和感数任务上，两组儿童的正确率差异不显著，但障碍组的反应时却显著长于对照组；(2)在阿拉伯数字比较任务和计数任务中，两组儿童的正确率及反应时均没有显著性差异；(3)在水平面任务上，与对照组相比，障碍组儿童的反应时有更长的趋势，差异呈边缘性显著。以上结果表明，发展性计算障碍儿童不存在数量转换困难，但其近似数量表征能力方面的明显不足可能是造成计算障碍的核心缺陷，并且提示计算障碍儿童的外部静态空间能力也存在一定程度的损伤。

关键词: 发展性计算障碍, 认知缺陷, 近似数量表征, 精确数量表征, 空间能力