返回抑制梯度效应的认知神经机制:来自ERP研究的证据

Neural Mechanisms of the Spatial Gradient Distribution of Inhibition of Return:Evidence from an ERP Study

通过操纵线索和靶刺激的空间关系,采用事件相关电位(ERP)技术探讨返回抑制梯度效应的脑内时程动态变化。结果发现,线索化条件下,P1波幅减小。在175-225ms内,线索化与相邻均比相对条件诱发了一个更大的负成分(Nd200),而且当返回抑制量大(线索化位置)时,Nd200更大。差异波(线索化-相对)的地形图显示,该负成分主要在额中部脑区有明显激活。在250-300ms内,线索化比相对条件同样诱发了一个更大的负成分(Nd270),差异波(线索化-相对)的地形图显示,该负成分主要在右侧顶部脑区有明显激活。结果表明,返回抑制梯度效应可能是由线索化位置的抑制和注意方向的转换共同引起的。

In the present study,high-density event - related potentials（ERPs） were recorded to investigate the spatial gradient distribution of inhibition of return（IOR）.Results showed that P1 suppression was observed for targets at a cued location.A later negative component（Nd200） was larger for the cued location.After that,a negative component at right parietal electrode sites （Nd270） appeared only at cued location,and did not show any general visual field effects.The results showed that IOR was caused by the perceptual suppression and the switch of attention orienting.