Lamb Sarah, Krieger Florian, Kuhn Jörg-Tobias
Department of Rehabilitation Sciences, TU Dortmund University, Dortmund, Germany.
Front Psychol. 2024 Jan 11;14:1187785. doi: 10.3389/fpsyg.2023.1187785. eCollection 2023.
Research suggests that children with developmental dyscalculia (DD) have deficits in basic numerical skills. However, there is conflicting evidence on whether basic numerical skills in children with DD are qualitatively different from those in typically developing children (TD) or whether basic numerical skills development in children with DD is simply delayed. In addition, there are also competing hypotheses about deficits in basic numerical skills, assuming (1) a general deficit in representing numerosities (Approximate Number System, ANS), (2) specific deficits in an object-based attentional system (Object Tracking System, OTS), or (3) deficits in accessing numerosities from symbols (Access Deficit, AD). Hence, the purpose of this study was to investigate whether deficits in basic numerical skills in children with DD are more indicative of a developmental delay or a dyscalculia-specific qualitative deviation and whether these deficits result from (selective) impairment of core cognitive systems involved in numerical processing. To address this, we tested 480 children (68 DD and 412 TD) in the 2nd, 3rd, and 4th grades with different paradigms for basic numerical skills (subitizing, counting, magnitude comparison tasks, number sets, and number line estimation tasks). The results revealed that DD children's impairments did not indicate qualitatively different basic numerical skills but instead pointed to a specific developmental delay, with the exception of dot enumeration. This result was corroborated when comparing mathematical profiles of DD children in 4th grade and TD children in 2nd grade, suggesting that DD children were developmentally delayed and not qualitatively different. In addition, specific deficits in core markers of numeracy in children with DD supported the ANS deficit rather than the AD and OTS deficit hypothesis.
研究表明，患有发育性计算障碍（DD）的儿童在基本数字技能方面存在缺陷。然而，关于DD儿童的基本数字技能在质上是否与正常发育儿童（TD）不同，或者DD儿童的基本数字技能发展是否只是延迟，存在相互矛盾的证据。此外，对于基本数字技能缺陷也存在相互竞争的假设，假设（1）在表示数量方面存在一般缺陷（近似数字系统，ANS），（2）基于对象的注意力系统（对象跟踪系统，OTS）存在特定缺陷，或者（3）从符号中获取数量存在缺陷（获取缺陷，AD）。因此，本研究的目的是调查DD儿童基本数字技能的缺陷是否更表明发育延迟或特定于计算障碍的质的偏差，以及这些缺陷是否源于参与数字处理的核心认知系统的（选择性）损伤。为了解决这个问题，我们用不同的基本数字技能范式（即时数数、计数、大小比较任务、数字集和数轴估计任务）对480名二、三、四年级的儿童（68名DD儿童和412名TD儿童）进行了测试。结果显示，DD儿童的损伤并不表明基本数字技能在质上不同，而是表明存在特定的发育延迟，但点计数除外。当比较四年级DD儿童和二年级TD儿童的数学概况时，这一结果得到了证实，表明DD儿童发育延迟，而非质上不同。此外，DD儿童在数字能力核心指标上的特定缺陷支持了ANS缺陷假说，而非AD和OTS缺陷假说。
