Rivera S M, Reiss A L, Eckert M A, Menon V
Department of Psychology, University of California, Davis, CA 94305-5719, USA.
Cereb Cortex. 2005 Nov;15(11):1779-90. doi: 10.1093/cercor/bhi055. Epub 2005 Feb 16.
Arithmetic reasoning is arguably one of the most important cognitive skills a child must master. Here we examine neurodevelopmental changes in mental arithmetic. Subjects (ages 8-19 years) viewed arithmetic equations and were asked to judge whether the results were correct or incorrect. During two-operand addition or subtraction trials, for which accuracy was comparable across age, older subjects showed greater activation in the left parietal cortex, along the supramarginal gyrus and adjoining anterior intra-parietal sulcus as well as the left lateral occipital temporal cortex. These age-related changes were not associated with alterations in gray matter density, and provide novel evidence for increased functional maturation with age. By contrast, younger subjects showed greater activation in the prefrontal cortex, including the dorsolateral and ventrolateral prefrontal cortex and the anterior cingulate cortex, suggesting that they require comparatively more working memory and attentional resources to achieve similar levels of mental arithmetic performance. Younger subjects also showed greater activation of the hippocampus and dorsal basal ganglia, reflecting the greater demands placed on both declarative and procedural memory systems. Our findings provide evidence for a process of increased functional specialization of the left inferior parietal cortex in mental arithmetic, a process that is accompanied by decreased dependence on memory and attentional resources with development.
算术推理可以说是儿童必须掌握的最重要的认知技能之一。在此，我们研究心算中的神经发育变化。研究对象（年龄在8至19岁之间）观看算术等式，并被要求判断结果是否正确。在两数相加或相减的试验中，各年龄组的准确率相当，年龄较大的受试者在左侧顶叶皮层、沿缘上回和相邻的顶内沟前部以及左侧枕颞叶皮层表现出更强的激活。这些与年龄相关的变化与灰质密度的改变无关，并为随着年龄增长功能成熟度增加提供了新证据。相比之下，较年轻的受试者在前额叶皮层表现出更强的激活，包括背外侧和腹外侧前额叶皮层以及前扣带回皮层，这表明他们需要相对更多的工作记忆和注意力资源来达到类似的心算表现水平。较年轻的受试者海马体和背侧基底神经节也表现出更强的激活，反映出对陈述性和程序性记忆系统的更大需求。我们的研究结果为心算中左侧顶下叶皮层功能专业化增强的过程提供了证据，这一过程伴随着随着发育对记忆和注意力资源的依赖减少。
