Ghent University.
University of Leuven.
J Cogn Neurosci. 2019 Mar;31(3):453-467. doi: 10.1162/jocn_a_01359. Epub 2018 Nov 20.
Multiplication is thought to be primarily solved via direct retrieval from memory. Two of the main factors known to influence the retrieval of multiplication facts are problem size and interference. Because these factors are often intertwined, we sought to investigate the unique influences of problem size and interference on both performance and neural responses during multiplication fact retrieval in healthy adults. Behavioral results showed that both problem size and interference explained separate unique portions of RT variance, but with significantly stronger contribution from problem size, which contrasts with previous work in children. Whole-brain fMRI results relying on a paradigm that isolated multiplication fact retrieval from response selection showed highly overlapping brain areas parametrically modulated by both problem size and interference in a large network of frontal, parietal, and subcortical brain areas. Subsequent analysis within these regions revealed problem size to be the stronger and more consistent "unique" modulating factor in overlapping regions as well as those that appeared to respond only to problem size or interference at the whole-brain level, thus underscoring the need to look beyond anatomical overlap using arbitrary thresholds. Additional unique contributions of interference (beyond problem size) were identified in right angular gyrus and subcortical regions associated with procedural processing. Together, our results suggest that problem size, relative to interference, tends to be the more dominant factor in driving behavioral and neural responses during multiplication fact retrieval in adults. Nevertheless, unique contributions of both factors demonstrate the importance of considering the overlapping and unique contributions of each in explaining the cognitive and neural bases of mental multiplication.
乘法被认为主要通过直接从记忆中检索来解决。已知有两个主要因素会影响乘法事实的检索，即问题大小和干扰。由于这些因素经常交织在一起，我们试图研究问题大小和干扰对健康成年人乘法事实检索的表现和神经反应的独特影响。行为结果表明，问题大小和干扰都解释了 RT 方差的单独独特部分，但问题大小的贡献明显更大，这与儿童的先前工作形成对比。全脑 fMRI 结果依赖于一种范式，该范式将乘法事实检索与反应选择隔离开来，结果表明在额叶、顶叶和皮质下大脑区域的大型网络中，问题大小和干扰以参数方式共同调节大脑区域。在这些区域内的后续分析表明，问题大小是重叠区域以及在全脑水平上似乎只对问题大小或干扰有反应的区域中更强和更一致的“独特”调节因素，从而强调需要超越使用任意阈值的解剖重叠。在与程序性处理相关的右角回和皮质下区域中，还确定了干扰（超过问题大小）的独特贡献。总的来说，我们的结果表明，与干扰相比，问题大小往往是成人乘法事实检索过程中驱动行为和神经反应的更主要因素。然而，两个因素的独特贡献表明，在解释心理乘法的认知和神经基础时，考虑每个因素的重叠和独特贡献是很重要的。
