Multiplication tables are typically memorized verbally, with fluent retrieval leading to better performance in advanced math. Arithmetic development is characterized by strategy shifts from procedural operations to direct fact retrieval, which would not necessitate access to the facts’ conceptual meaning. This study tested this hypothesis using a combination of event related brain potentials (ERP) and behavioral measures with 3rd-5th grade children and young adults. Participants verified the solutions to simple multiplication problems (2 × 3 = 6 or = 7) and the semantic fit of word-picture pairs, separately. Children showed an N400 effect to multiplication solutions with larger (more negative) amplitude for incorrect than correct solutions, reflecting meaning-level processing. A similar ERP response was observed in the word-picture verification task, with larger negative amplitude for word-picture pairs that were semantically mismatched compared to matched. In contrast, adults showed a P300 response for correct solutions, suggesting that they treated these solutions as potential targets in over-rehearsed mathematical expressions. This P300 response was specific to math fact processing, as the word-picture verification task elicited a classic N400 in adults. These ERP findings reveal an overlooked developmental transition that occurs after fifth grade, and speak to theories of arithmetic that have been based primarily on adult data.

乘法表通常是口头记忆的，流畅的检索可以提高高等数学的表现。算术开发的特点是策略从程序运算转向直接事实检索，这不需要访问事实的概念含义。这项研究结合了事件相关脑电位 (ERP) 和行为测量，对 3 至 5 年级的儿童和年轻人测试了这一假设。参与者分别验证了简单乘法问题（2 × 3 = 6 或 = 7）的解决方案以及单词-图片对的语义拟合。儿童对乘法解法表现出 N400 效应，错误解法的幅度比正确解法的幅度更大（更负），反映了意义层面的处理。在文字-图片验证任务中观察到类似的 ERP 响应，与匹配相比，语义不匹配的文字-图片对的负振幅更大。相比之下，成年人对正确的解决方案表现出 P300 反应，这表明他们将这些解决方案视为过度演练的数学表达式的潜在目标。这种 P300 反应是针对数学事实处理的，因为文字-图片验证任务在成人中引发了经典的 N400 反应。这些 ERP 研究结果揭示了五年级后发生的一个被忽视的发展转变，并涉及主要基于成人数据的算术理论。