Key Laboratory of Cognition and Personality, Southwest University, Ministry of Education, Chongqing, China.
Exp Brain Res. 2012 Sep;221(3):279-85. doi: 10.1007/s00221-012-3170-0. Epub 2012 Jul 13.
Although the inhibition of return (IOR) effect in exogenous orienting has been investigated extensively with the Posnerian cuing paradigm, there has been little evidence for the role of attentional processes in the IOR effect. The N2pc component was used as a marker of the deployment of spatial attention to isolate attentional processes in the IOR effect. Participants responded to task-relevant target displays that were preceded by cue displays in a non-predictive, exogenous cuing paradigm. A 1,000 ms of stimulus onset asynchrony (SOA) was designed to investigate the IOR effect. Behavioral results indicate that the SOA was sufficiently long to cause an IOR effect in the discrimination task. As for ERP patterns elicited by targets, the N2pc amplitudes were similar across cue types, but the N2pc latency was delayed when targets appeared at the cued location rather than at the uncued location. N2pc patterns demonstrated that the spatial attentional process is indeed an important mechanism underlying the IOR effect. The delayed N2pc for targets in the valid cue type suggested that IOR effect may reflect a delayed deployment of spatial attention to targets appearing at recently cued locations.
尽管在外部定向中已广泛研究了抑制返回（IOR）效应，但在 IOR 效应中注意力过程的作用却鲜有证据。N2pc 成分被用作标记空间注意力的部署，以在 IOR 效应中分离注意力过程。参与者在非预测性的外部线索范式中对任务相关的目标显示做出响应，该范式以前有线索显示。设计了 1000 毫秒的刺激呈现时间间隔（SOA），以研究 IOR 效应。行为结果表明，SOA 足够长，足以在辨别任务中引起 IOR 效应。至于由目标引发的 ERP 模式，N2pc 幅度在不同的线索类型之间相似，但当目标出现在有线索的位置而不是无线索的位置时，N2pc 潜伏期会延迟。N2pc 模式表明，空间注意力过程确实是 IOR 效应的重要机制。在有效线索类型中目标的 N2pc 延迟表明，IOR 效应可能反映了对最近有线索的位置出现的目标的空间注意力的延迟部署。
