Ashkenazi Sarit, Tikochinski Refael, Ganor-Stern Dana
Learning Disabilities, The Seymour Fox School of Education, The Hebrew University of Jerusalem, Jerusalem 9190501, Israel.
Technion, Israel Institute of Technology, Haifa 3200003, Israel.
Brain Sci. 2022 Mar 7;12(3):357. doi: 10.3390/brainsci12030357.
Computation estimation is the ability to provide an approximate answer to a complex arithmetic problem without calculating it exactly. Despite its importance in daily life, the neuronal network underlying computation estimation is largely unknown.
We looked at the neuronal correlates of two computational estimation strategies: approximated calculation and sense of magnitude (SOM)-intuitive representation of magnitude, without calculation. During an fMRI scan, thirty-one college students judged whether the result of a two-digit multiplication problem was larger or smaller than a given reference number. In two different blocks, they were asked to use a specific strategy (AC or SOM).
The two strategies activated brain regions related to calculation, numerical cognition, decision-making, and working memory. AC more than SOM elicited activations in multiple, domain-specific brain regions in the parietal lobule, including the left SMG (BA 40), the bilateral superior parietal lobule (BA 7), and the right inferior parietal lobule (BA 7). The activation level of the IFG was positively correlated to individual accuracy, indicating that the IFG has an essential role in both strategies.
These finding suggest that the analogic code of magnitude is more involved in the AC than the SOM strategy.
计算估计是指在不精确计算的情况下为复杂算术问题提供近似答案的能力。尽管其在日常生活中很重要，但计算估计背后的神经网络在很大程度上仍不为人所知。
我们研究了两种计算估计策略的神经元相关性：近似计算和数量感（SOM）——数量的直观表示，无需计算。在功能磁共振成像扫描期间，31名大学生判断两位数乘法问题的结果是大于还是小于给定的参考数字。在两个不同的组块中，要求他们使用特定的策略（近似计算或数量感）。
这两种策略激活了与计算、数字认知、决策和工作记忆相关的脑区。与数量感策略相比，近似计算策略在顶叶小叶的多个特定领域脑区引发了更多激活，包括左侧角回（BA 40）、双侧顶上小叶（BA 7）和右侧顶下小叶（BA 7）。额下回的激活水平与个体准确性呈正相关，表明额下回在两种策略中都起着至关重要的作用。
这些发现表明，与数量感策略相比，近似计算策略更多地涉及数量的类比编码。
