Riemer Martin, Diersch Nadine, Bublatzky Florian, Wolbers Thomas
Aging & Cognition Research Group, German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany.
Department of Psychology, School of Social Sciences, University of Mannheim, Mannheim, Germany.
Neuroimage. 2016 Apr 1;129:72-79. doi: 10.1016/j.neuroimage.2016.01.030. Epub 2016 Jan 22.
The mental representations of space, time, and number magnitude are inherently linked. The right posterior parietal cortex (PPC) has been suggested to contain a general magnitude system that underlies the overlap between various perceptual dimensions. However, comparative studies including spatial, temporal, and numerical dimensions are missing. In a unified paradigm, we compared the impact of right PPC inhibition on associations with spatial response codes (i.e., Simon, SNARC, and STARC effects) and on congruency effects between space, time, and numbers. Prolonged cortical inhibition was induced by continuous theta-burst stimulation (cTBS), a protocol for transcranial magnetic stimulation (TMS), at the right intraparietal sulcus (IPS). Our results show that congruency effects, but not response code associations, are affected by right PPC inhibition, indicating different neuronal mechanisms underlying these effects. Furthermore, the results demonstrate that interactions between space and time perception are reflected in congruency effects, but not in an association between time and spatial response codes. Taken together, these results implicate that the congruency between purely perceptual dimensions is processed in PPC areas along the IPS, while the congruency between percepts and behavioral responses is independent of this region.
空间、时间和数字大小的心理表征内在地联系在一起。右后顶叶皮层（PPC）被认为包含一个通用的大小系统，该系统是各种感知维度之间重叠的基础。然而，缺乏包括空间、时间和数字维度的比较研究。在一个统一的范式中，我们比较了右PPC抑制对与空间反应编码（即西蒙效应、SNARC效应和STARC效应）的关联以及对空间、时间和数字之间一致性效应的影响。通过连续theta爆发刺激（cTBS）诱导长时间的皮层抑制，cTBS是一种经颅磁刺激（TMS）方案，作用于右侧顶内沟（IPS）。我们的结果表明，一致性效应而非反应编码关联受右PPC抑制的影响，这表明这些效应背后存在不同的神经元机制。此外，结果表明空间和时间感知之间的相互作用反映在一致性效应中，而不是时间与空间反应编码之间的关联中。综上所述，这些结果表明，纯感知维度之间的一致性在沿IPS的PPC区域中进行处理，而感知与行为反应之间的一致性则独立于该区域。
