Wild-Wall Nele, Falkenstein Michael, Hohnsbein Joachim
Institute for Occupational Physiology, University of Dortmund, Ardeystr. 67 D-44139, Dortmund, Germany.
Brain Res. 2008 May 23;1211:72-84. doi: 10.1016/j.brainres.2008.03.025. Epub 2008 Mar 21.
The present study investigates behavioural and event-related potential (ERP) differences between young and older participants in two variants of a flanker task. Flankers preceded the target by 100 ms (Experiment 1) or were presented simultaneously with the target (Experiment 2). In both experiments the response times showed an age-related slowing and a compatibility effect, which did not differ significantly across age. The older participants committed only half as many errors as the young ones. The visual ERPs revealed that the speed of visual perception was similar between groups. In addition the processing of the targets, but not of the flankers, appeared to be enhanced in the older participants. Moreover the lateralized readiness potential (LRP) started later and was larger for old vs. young participants, which was most pronounced for the incorrect LRP activation due to the flankers. The LRP amplitude effect is due to an enhanced activation over contralateral motor areas, which appears to be a general finding unrelated to the error rate. In summary, in the present study we could not find evidence for enhanced flanker interference in the performance of older compared to young participants. The reduced error rates for older participants are likely due to enhanced processing of the targets and delayed transmission of flanker information from visual to motor areas.
本研究调查了在侧翼任务的两种变体中，年轻参与者和年长参与者之间的行为及事件相关电位（ERP）差异。侧翼刺激在目标刺激之前100毫秒呈现（实验1），或与目标刺激同时呈现（实验2）。在两个实验中，反应时间均显示出与年龄相关的减慢以及相容性效应，且在不同年龄组之间无显著差异。年长参与者犯的错误仅为年轻参与者的一半。视觉ERP显示，两组之间的视觉感知速度相似。此外，年长参与者对目标刺激的加工增强，而对侧翼刺激的加工未增强。而且，年长参与者的侧化准备电位（LRP）起始时间更晚且幅度更大，这在由侧翼刺激导致的错误LRP激活中最为明显。LRP幅度效应是由于对侧运动区域的激活增强，这似乎是一个与错误率无关的普遍发现。总之，在本研究中，我们未发现与年轻参与者相比，年长参与者在任务表现中侧翼干扰增强的证据。年长参与者错误率降低可能是由于对目标刺激的加工增强以及侧翼刺激信息从视觉区域到运动区域的传递延迟。
