Durgin Frank H, Portley Makayla
Department of Psychology, Swarthmore College.
J Exp Psychol Hum Percept Perform. 2023 Apr;49(4):483-495. doi: 10.1037/xhp0001106. Epub 2023 Apr 13.
The approximate number system (ANS) is widely regarded as handling numbers beyond the subitizing range. However, a review of a variety of historical data suggests there is a sharp break in the estimation of visuospatial number at about 20 items. Estimates below 20 tend to be unbiased. Those above 20 tend to show underestimation that can be well-fit by a power function with an exponent less than one. Here we manipulate display duration between subjects to confirm that this break is not simply an artifact of brief displays, but seems to reflect a shift in perceptual magnitude estimation from an ANS (unbiased estimation) to a correlated numerosity system (with log scaling). Detailed analysis of both response time and variability suggests that the sharp break at 20 observed here may reflect a capacity limitation in a linear accumulator system, which gives way to alternative magnitude information beyond 20. Implications for studies of number comparison and math performance are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
近似数系统（ANS）被广泛认为用于处理超出一眼识数范围的数字。然而，对各种历史数据的回顾表明，在大约20个项目时，视觉空间数字估计存在明显的断点。20以下的估计往往是无偏差的。20以上的估计往往表现出低估，可用指数小于1的幂函数很好地拟合。在这里，我们在受试者之间操纵显示持续时间，以确认这种断点不仅仅是短暂显示的人为产物，而是似乎反映了感知量级估计从近似数系统（无偏差估计）到相关数量系统（对数缩放）的转变。对反应时间和变异性的详细分析表明，这里观察到的20处的明显断点可能反映了线性累加器系统中的容量限制，超过20时则让位于其他量级信息。讨论了对数字比较和数学表现研究的启示。（PsycInfo数据库记录（c）2023美国心理学会，保留所有权利）
