Milosavljevic Milica, Madsen Erik, Koch Christof, Rangel Antonio
Computation and Neural Systems, California Institute of Technology, Pasadena, CA 91125, USA.
J Vis. 2011 Apr 6;11(4):4. doi: 10.1167/11.4.4.
Visual psychophysicists have recently developed tools to measure the maximal speed at which the brain can accurately carry out different types of computations (H. Kirchner & S. J. Thorpe, 2006). We use this methodology to measure the maximal speed with which individuals can make magnitude comparisons between two single-digit numbers. We find that individuals make such comparisons with high accuracy in 306 ms on average and are able to perform above chance in as little as 230 ms. We also find that maximal speeds are similar for "larger than" and "smaller than" number comparisons and in a control task that simply requires subjects to identify the number in a number-letter pair. The results suggest that the brain contains dedicated processes involved in implementing basic number comparisons that can be deployed in parallel with processes involved in low-level visual processing.
视觉心理物理学家最近开发出了一些工具，用于测量大脑能够准确执行不同类型计算的最大速度（H. 基尔希纳和S. J. 索普，2006年）。我们使用这种方法来测量个体对两个一位数进行大小比较的最大速度。我们发现，个体平均在306毫秒内就能以高精度进行此类比较，并且在短短230毫秒内就能表现出高于随机水平的能力。我们还发现，对于“大于”和“小于”数字比较以及一项仅要求受试者识别数字字母对中数字的对照任务，最大速度是相似的。结果表明，大脑中存在专门用于执行基本数字比较的过程，这些过程可以与低级视觉处理中涉及的过程并行部署。
