内源性注意定向对立体视觉加工影响的ERP研究

The Effect of Endogenous Attentional Orienting on Stereopsis:an ERP Study

本研究采用行为测量与ERP分析相结合的范式,以视差分离方式、线索提示有效性为自变量,考察三维空间中内源性注意定向对立体视觉加工的影响及其脑电机制。结果发现:无论是短SOA还是长SOA,3D空间中预测性中央符号线索对后续辨认任务均产生了启动效应,且启动效应量不随SOA延长而变化。短SOA下,经典提示效应和跨深度提示效应均表现为有效提示下的N1波幅大于无效提示条件;长SOA下,线索提示效应则表现出了无效提示条件诱发较大N1波幅的趋势。

The effect of attention orienting on visual processing has been studied intensively in cognitive psychology.Based on the spatial cueing paradigm,Posner distinguished endogenous orienting from the exogenous orienting,and it was commonly confirmed in 2D plane studies that there were many differences between the two.The effect of endogenous orienting was more sensitive to distracters,less influenced by SOA,and might have different brain mechanism.However,the effect of endogenous attention orienting on stereopsis is still lack of evidence and worth exploring. Employing a behavioral paradigm combined with the ERP technique,the present research was aimed at exploring how endogenous orienting influenced depth processing.We used a2（cue duration;200ms;1000ms）×4（cue validity：cue and target at the same location and depth;they on different sides,but at the same depth plane;they in different depth planes,but at the same x - y coordinates; they on different sides,both in different depth planes） within - subjects design.In the experiment,the participants wore the liquid crystal stereo glasses.At the beginning of a trial,a fixation point was displayed on a computer screen for 1200ms,then the predictive central symbolic cue was presented for 200ms or 1000ms,the participants were instructed to pay attention to the direction of the cue to maximize the correct rate.And finally,the target was displayed for 100ms,the participants were instructed to press the ＂ 1＂ key on the Stimpad for an H target and the ＂4＂ key for an S target as quickly as possible.After a 1500ms blank,another trial was started.The results showed：At both the short and the long SOA,the cue produced a facilitative effect on the discrimination task,and the difference between the two treatments was not statistically significant.At the short SOA,both the classic and the cross - depth facilitative effect affected N1 wave,in which the valid -cue trials induced a larger N1 amplitude;while at the long SOA,the invalid -cue trials tended to induce a larger N1 amplitude. The findings suggest that the facilitative effect of the endogenous orienting on stereopsis is stable and consistent.But the brain mechanism underlying the short - term cue and the long - term cue may be different.