Parametric effects of numerical distance on the intraparietal sulcus during passive viewing of rapid numerosity changes
Parametric effects of numerical distance on the intraparietal sulcus during passive viewing of rapid numerosity changes
复制标题
DOI：
10.1016/j.brainres.2005.10.083
复制
发表时间：
2006-01-05
期刊：
影响因子：
2.9
通讯作者：
Siong, SC
中科院分区：
文献类型：
--
作者：
Ansari, D;Dhital, B;Siong, SC
许多功能性神经影像学研究表明，顶内沟（IPS）内和周围的区域是由数值距离参数调制的，因此距离和激活水平之间存在反比关系。因此，这些区域被认为包含了数量级的内部表征。然而，也有人建议，IPS参与在数字比较任务的响应选择，而不是本身的数值大小的表示。为了检验距离对皮层区域影响的独立性，我们采用了被动观察范式。16名惯用右手的男性参与者观看了包含正方形阵列的快速变化的幻灯片。通过改变不同区块中呈现的数值之间的距离（8与8，8与12，8与16），我们检查了哪些区域表现出数值距离的参数效应。该分析揭示了双侧IPS的上级部分以及上级顶叶小叶和缘上回的这种效应。相比之下，载玻片的面积而不是数量（面积常数、面积x 1和面积x 2）快速变化，不会在这些区域中产生距离的参数效应。相反，在距状沟的一个区域发现了面积的反向效应。这些研究结果表明，在没有明确的任务和响应要求的情况下，IPS内和周围的区域参与了数值幅度歧视。(c)2005爱思唯尔有限公司版权所有
A number of functional neuroimaging studies have revealed that regions in and around the intraparietal sulcus (IPS) are parametrically modulated by numerical distance, whereby there is an inverse relationship between distance and levels of activation. These areas are thus thought to contain the internal representation of numerical magnitude. Nevertheless, it has also been suggested that the IPS is involved in response selection during number comparison tasks rather than the representation of numerical magnitude per se. In order to test the independence of the effect of distance on cortical regions, we employed a passive viewing paradigm. Sixteen right-handed male participants viewed rapidly changing slides containing arrays of squares. By varying the distance between the numerosity presented in separate blocks (8 vs. 8, 8 vs. 12, and 8 vs. 16), we examined which regions exhibit a parametric effect of numerical distance. This analysis revealed such effects in the superior part of the IPS bilaterally as well as the superior parietal lobule and the supramarginal gyrus. In contrast, slides rapidly changing in area but not number (Area constant, Area x 1, and Area x 2) did not yield a parametric effect of distance in these regions. Instead, a reverse effect of area was found in a region of the calcarine sulcus. These findings suggest that areas in and around the IPS are involved in numerical magnitude discrimination in the absence of an explicit task and response requirements. (c) 2005 Elsevier B.V. All rights reserved