Knakker Balázs, Weiss Béla, Vidnyánszky Zoltán
Brain Imaging Centre, Research Centre for Natural Sciences, Hungarian Academy of Sciences Budapest, Hungary ; Faculty of Information Technology and Bionics, Pázmány Péter Catholic University Budapest, Hungary.
Brain Imaging Centre, Research Centre for Natural Sciences, Hungarian Academy of Sciences Budapest, Hungary.
Front Hum Neurosci. 2015 Jan 12;8:1048. doi: 10.3389/fnhum.2014.01048. eCollection 2014.
Visual cortical alpha oscillations are involved in attentional gating of incoming visual information. It has been shown that spatial and feature-based attentional selection result in increased alpha oscillations over the cortical regions representing sensory input originating from the unattended visual field and task-irrelevant visual features, respectively. However, whether attentional gating in the case of object based selection is also associated with alpha oscillations has not been investigated before. Here we measured anticipatory electroencephalography (EEG) alpha oscillations while participants were cued to attend to foveal face or word stimuli, the processing of which is known to have right and left hemispheric lateralization, respectively. The results revealed that in the case of simultaneously displayed, overlapping face and word stimuli, attending to the words led to increased power of parieto-occipital alpha oscillations over the right hemisphere as compared to when faces were attended. This object category-specific modulation of the hemispheric lateralization of anticipatory alpha oscillations was maintained during sustained attentional selection of sequentially presented face and word stimuli. These results imply that in the case of object-based attentional selection-similarly to spatial and feature-based attention-gating of visual information processing might involve visual cortical alpha oscillations.
视觉皮层的阿尔法振荡参与传入视觉信息的注意力门控。研究表明，基于空间和特征的注意力选择分别导致代表来自未注意视野的感觉输入和任务无关视觉特征的皮层区域的阿尔法振荡增加。然而，基于对象选择情况下的注意力门控是否也与阿尔法振荡相关，此前尚未得到研究。在这里，我们测量了参与者在被提示关注中央凹面部或单词刺激时的预期脑电图（EEG）阿尔法振荡，已知对这两种刺激的处理分别具有右半球和左半球的偏侧化。结果显示，在同时呈现、重叠的面部和单词刺激的情况下，与关注面部时相比，关注单词会导致右半球顶枕部阿尔法振荡的功率增加。在对顺序呈现的面部和单词刺激进行持续注意力选择期间，预期阿尔法振荡半球偏侧化的这种对象类别特异性调制得以维持。这些结果表明，在基于对象的注意力选择情况下，与基于空间和特征的注意力一样，视觉信息处理的门控可能涉及视觉皮层的阿尔法振荡。
