Jordan N C, Montani T O
Department of Educational Studies, University of Delaware, Newark 19716, USA. njordan@.udel.edu
J Learn Disabil. 1997 Nov-Dec;30(6):624-34, 684. doi: 10.1177/002221949703000606.
This study examined problem-solving and number-fact skills in two subgroups of third-grade children with mathematics difficulties (MD): MD-specific (n = 12) and MD-general (n = 12). The MD-specific group had difficulties in mathematics but not in reading, and the MD-general group had difficulties in reading as well as in mathematics. A comparison group of nonimpaired children (n = 24) also was included. The findings showed that on both story and number-fact problems, the MD-specific group performed worse than the nonimpaired group in timed conditions but not in untimed conditions. The MD-general group, on the other hand, performed worse than the nonimpaired group, regardless of whether tasks were timed or not. An analysis of children's strategies in untimed conditions showed that both the MD-specific and the MD-general groups relied more on backup strategies than the nonimpaired group. However, children in the MD-specific group executed backup strategies more skillfully than children in the MD-general group, allowing them to achieve parity with children in the nonimpaired group when tasks were not timed. The findings suggest that children with specific MD have circumscribed deficits associated with fact retrieval, whereas children with general MD have more basic delays associated with problem conceptualization and execution of calculation procedures.
本研究考察了三年级数学困难（MD）儿童两个亚组的问题解决能力和数字运算技能：特定数学困难组（n = 12）和一般数学困难组（n = 12）。特定数学困难组在数学方面有困难，但阅读方面没有困难，而一般数学困难组在阅读和数学方面都有困难。还纳入了一个未受损儿童对照组（n = 24）。研究结果表明，在故事问题和数字运算问题上，特定数学困难组在限时条件下的表现比未受损组差，但在不限时条件下并非如此。另一方面，无论任务是否限时，一般数学困难组的表现都比未受损组差。对儿童在不限时条件下策略的分析表明，特定数学困难组和一般数学困难组比未受损组更多地依赖备用策略。然而，特定数学困难组的儿童执行备用策略比一般数学困难组的儿童更熟练，这使得他们在任务不限时的情况下能够与未受损组的儿童表现相当。研究结果表明，特定数学困难儿童存在与事实检索相关的局限性缺陷，而一般数学困难儿童存在与问题概念化和计算程序执行相关的更基本的延迟。
