Université catholique de Louvain, Belgium.
Educational Neuroscience, Institute of Psychology, University of Graz, Austria.
Neuroimage. 2018 May 15;172:718-727. doi: 10.1016/j.neuroimage.2018.01.060. Epub 2018 Feb 11.
In the development of math ability, a large variability of performance in solving simple arithmetic problems is observed and has not found a compelling explanation yet. One robust effect in simple multiplication facts is the problem size effect, indicating better performance for small problems compared to large ones. Recently, behavioral studies brought to light another effect in multiplication facts, the interference effect. That is, high interfering problems (receiving more proactive interference from previously learned problems) are more difficult to retrieve than low interfering problems (in terms of physical feature overlap, namely the digits, De Visscher and Noël, 2014). At the behavioral level, the sensitivity to the interference effect is shown to explain individual differences in the performance of solving multiplications in children as well as in adults. The aim of the present study was to investigate the individual differences in multiplication ability in relation to the neural interference effect and the neural problem size effect. To that end, we used a paradigm developed by De Visscher, Berens, et al. (2015) that contrasts the interference effect and the problem size effect in a multiplication verification task, during functional magnetic resonance imaging (fMRI) acquisition. Forty-two healthy adults, who showed high variability in an arithmetic fluency test, participated in our fMRI study. In order to control for the general reasoning level, the IQ was taken into account in the individual differences analyses. Our findings revealed a neural interference effect linked to individual differences in multiplication in the left inferior frontal gyrus, while controlling for the IQ. This interference effect in the left inferior frontal gyrus showed a negative relation with individual differences in arithmetic fluency, indicating a higher interference effect for low performers compared to high performers. This region is suggested in the literature to be involved in resolution of proactive interference. Besides, no correlation between the neural problem size effect and multiplication performance was found. This study supports the idea that the interference due to similarities/overlap of physical traits (the digits) is crucial in memorizing arithmetic facts and in determining individual differences in arithmetic.
在数学能力的发展过程中，人们观察到解决简单算术问题的表现存在很大的可变性，但尚未找到令人信服的解释。一个在简单乘法事实中稳健的效应是问题大小效应，表明与大问题相比，小问题的表现更好。最近，行为研究揭示了乘法事实中的另一个效应，即干扰效应。也就是说，高干扰问题（从之前学习的问题中受到更多的前摄干扰）比低干扰问题（就物理特征重叠而言，即数字）更难检索，De Visscher 和 Noël，2014）。在行为层面上，对干扰效应的敏感性表明，它可以解释儿童和成人在解决乘法问题时表现的个体差异。本研究的目的是调查与神经干扰效应和神经问题大小效应相关的乘法能力的个体差异。为此，我们使用了 De Visscher、Berens 等人开发的范式（2015 年），该范式在功能磁共振成像（fMRI）采集期间对比了乘法验证任务中的干扰效应和问题大小效应。42 名健康成年人参加了我们的 fMRI 研究，他们在算术流畅性测试中表现出很高的可变性。为了控制一般推理水平，在个体差异分析中考虑了智商。我们的发现揭示了与乘法个体差异相关的左额下回的神经干扰效应，同时控制了智商。左额下回的这种干扰效应与算术流畅性的个体差异呈负相关，表明低表现者的干扰效应高于高表现者。该区域在文献中被认为参与了前摄干扰的解决。此外，没有发现神经问题大小效应与乘法表现之间的相关性。这项研究支持了这样一种观点，即由于物理特征（数字）的相似性/重叠而产生的干扰对于记忆算术事实和确定算术的个体差异至关重要。
