Halberda Justin, Feigenson Lisa
Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218, USA.
Dev Psychol. 2008 Sep;44(5):1457-65. doi: 10.1037/a0012682.
Behavioral, neuropsychological, and brain imaging research points to a dedicated system for processing number that is shared across development and across species. This foundational Approximate Number System (ANS) operates over multiple modalities, forming representations of the number of objects, sounds, or events in a scene. This system is imprecise and hence differs from exact counting. Evidence suggests that the resolution of the ANS, as specified by a Weber fraction, increases with age such that adults can discriminate numerosities that infants cannot. However, the Weber fraction has yet to be determined for participants of any age between 9 months and adulthood, leaving its developmental trajectory unclear. Here we identify the Weber fraction of the ANS in 3-, 4-, 5-, and 6-year-old children and in adults. We show that the resolution of this system continues to increase throughout childhood, with adultlike levels of acuity attained surprisingly late in development.
行为、神经心理学和脑成像研究表明，存在一个专门用于处理数字的系统，该系统在不同发育阶段和不同物种间共享。这个基础的近似数系统（ANS）通过多种模态运行，形成场景中物体、声音或事件数量的表征。该系统不精确，因此与精确计数不同。有证据表明，由韦伯分数所规定的ANS分辨率会随着年龄增长而提高，以至于成年人能够区分婴儿无法区分的数字大小。然而，9个月至成年之间任何年龄的参与者的韦伯分数尚未确定，其发育轨迹尚不清楚。在这里，我们确定了3岁、4岁、5岁和6岁儿童以及成年人的ANS韦伯分数。我们发现，该系统的分辨率在整个童年时期持续提高，令人惊讶的是，直到发育后期才达到类似成人的敏锐度水平。
