Dewind Nicholas K, Brannon Elizabeth M
Center for Cognitive Neuroscience, Levine Science Research Center, Duke University, Durham, NC, USA.
Front Hum Neurosci. 2012 Apr 19;6:68. doi: 10.3389/fnhum.2012.00068. eCollection 2012.
Prior research demonstrates that animals and humans share an approximate number system (ANS), characterized by ratio dependence and that the precision of this system increases substantially over human development. The goal of the present research was to investigate the malleability of the ANS (as measured by Weber fraction) in adult subjects in response to feedback and to explore the relationship between ANS acuity and acuity on another magnitude comparison task. We tested each of 20 subjects over six 1-h sessions. The main findings were that (a) Weber fractions rapidly decreased when trial-by-trial feedback was introduced in the second session and remained stable over continued training, (b) Weber fractions remained steady when trial-by-trial feedback was removed in session 6, (c)Weber fractions from the number comparison task were positively correlated with Weber fractions from a line length comparison task, (d) improvement in Weber fractions in response to feedback for the number task did not transfer to the line length task, (e) finally, the precision of the ANS was positively correlated with math, but not verbal, standardized aptitude scores. Potential neural correlates of the perceptual information and decision processes are considered, and predictions regarding the neural correlates of ANS malleability are discussed.
先前的研究表明，动物和人类共享一个近似数字系统（ANS），其特征是比率依赖性，并且该系统的精度在人类发展过程中会大幅提高。本研究的目的是调查成年受试者中ANS的可塑性（通过韦伯分数衡量）对反馈的反应，并探索ANS敏锐度与另一量级比较任务的敏锐度之间的关系。我们在六个1小时的时段内对20名受试者进行了测试。主要发现如下：（a）在第二时段引入逐次试验反馈时，韦伯分数迅速下降，并在持续训练中保持稳定；（b）在第6时段去除逐次试验反馈时，韦伯分数保持稳定；（c）数字比较任务中的韦伯分数与线长比较任务中的韦伯分数呈正相关；（d）数字任务中因反馈导致的韦伯分数改善并未转移到线长任务中；（e）最后，ANS的精度与数学标准化能力得分呈正相关，但与语言标准化能力得分无关。我们考虑了感知信息和决策过程的潜在神经关联，并讨论了关于ANS可塑性神经关联的预测。
