Ligeza Tomasz S, Tymorek Agnieszka D, Wyczesany Mirosław
Psychophysiology Laboratory, Institute of Psychology Jagiellonian University, Kraków, Poland;
Psychophysiology Laboratory, Institute of Psychology Jagiellonian University, Kraków, Poland.
Acta Neurobiol Exp (Wars). 2017;77(4):305-316.
Limited attention capacity results that not all the stimuli present in the visual field are equally processed. While processing of salient stimuli is automatically boosted by bottom‑up attention, processing of task‑relevant stimuli can be boosted volitionally by top‑down attention. Usually, both top‑down and bottom‑up influences are present simultaneously, which creates a competition between these two types of attention. We examined this competition using both behavioral and electrophysiological measures. Participants responded to letters superimposed on background pictures. We assumed that responding to different conditions of the letter task engages top‑down attention to different extent, whereas processing of background pictures of varying salience engages bottom‑up attention to different extent. To check how manipulation of top‑down attention influences bottom‑up processing, we measured evoked response potentials (ERPs) in response to pictures (engaging mostly bottom‑up attention) during three conditions of a letter task (different levels of top‑down engagement). Conversely, to check how manipulation of bottom‑up attention influences top‑down processing, we measured ERP responses for letters (engaging mostly top‑down attention) while manipulating the salience of background pictures (different levels of bottom‑up engagement). The correctness and reaction times in response to letters were also analyzed. As expected, most of the ERPs and behavioral measures revealed a trade‑off between both types of processing: a decrease of bottom‑up processing was associated with an increase of top‑down processing and, similarly, a decrease of top‑down processing was associated with an increase in bottom‑up processing. Results proved competition between the two types of attentions.
注意力容量有限导致视野中呈现的所有刺激并非都能得到同等程度的处理。虽然显著刺激的处理会通过自下而上的注意力自动增强，但与任务相关刺激的处理可以通过自上而下的注意力有意增强。通常，自上而下和自下而上的影响会同时存在，这就导致了这两种注意力之间的竞争。我们使用行为学和电生理学方法研究了这种竞争。参与者对叠加在背景图片上的字母做出反应。我们假设，对字母任务不同条件的反应会在不同程度上调用自上而下的注意力，而对不同显著程度背景图片的处理会在不同程度上调用自下而上的注意力。为了检验自上而下注意力的操控如何影响自下而上的处理，我们在字母任务的三种条件下（自上而下参与程度不同）测量了对图片（主要调用自下而上的注意力）的诱发反应电位（ERP）。相反，为了检验自下而上注意力的操控如何影响自上而下的处理，我们在操控背景图片的显著程度（自下而上参与程度不同）时测量了对字母的ERP反应（主要调用自上而下的注意力）。我们还分析了对字母反应的正确性和反应时间。正如预期的那样，大多数ERP和行为测量结果都显示出这两种处理之间的权衡：自下而上处理的减少与自上而下处理的增加相关，同样，自上而下处理的减少与自下而上处理的增加相关。结果证明了两种注意力之间的竞争。
