Liu Yuelu, Bengson Jesse, Huang Haiqing, Mangun George R, Ding Mingzhou
J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL 32611, USA Center for Mind and Brain, University of California, Davis, Davis, CA 95618, USA.
Center for Mind and Brain, University of California, Davis, Davis, CA 95618, USA.
Cereb Cortex. 2016 Feb;26(2):517-29. doi: 10.1093/cercor/bhu204. Epub 2014 Sep 9.
In covert visual attention, frontoparietal attention control areas are thought to issue signals to selectively bias sensory neurons to facilitate behaviorally relevant information and suppress distraction. We investigated the relationship between activity in attention control areas and attention-related modulation of posterior alpha activity using simultaneous electroencephalography (EEG) and functional magnetic resonance imaging in humans during cued visual-spatial attention. Correlating single-trial EEG alpha power with blood-oxygen-level dependent (BOLD) activity, we found that BOLD in the intraparietal sulcus (IPS) and left middle frontal gyrus was inversely correlated with occipital alpha power. Importantly, in IPS, inverse correlations were stronger for alpha within the hemisphere contralateral to the attended hemifield, implicating the IPS in the enhancement of task-relevant sensory areas. Positive BOLD-alpha correlations were observed in sensorimotor cortices and the default mode network, suggesting a mechanism of active suppression over task-irrelevant areas. The magnitude of cue-induced alpha lateralization was positively correlated with BOLD in dorsal anterior cingulate cortex and dorsolateral prefrontal cortex, implicating a role of executive control in attention. These results show that IPS and frontal executive areas are the main sources of biasing influences on task-relevant visual cortex, whereas task-irrelevant default mode network and sensorimotor cortex are inhibited during visual attention.
在隐蔽视觉注意中，额顶叶注意控制区域被认为会发出信号，以选择性地偏向感觉神经元，从而促进行为相关信息并抑制干扰。我们在人类进行线索化视觉空间注意时，使用同步脑电图（EEG）和功能磁共振成像，研究了注意控制区域的活动与后阿尔法活动的注意相关调制之间的关系。将单次试验的脑电图阿尔法功率与血氧水平依赖（BOLD）活动相关联，我们发现顶内沟（IPS）和左额中回的BOLD与枕叶阿尔法功率呈负相关。重要的是，在IPS中，与被注意半视野对侧半球内的阿尔法的负相关更强，这表明IPS参与了任务相关感觉区域的增强。在感觉运动皮层和默认模式网络中观察到正的BOLD-阿尔法相关性，表明对任务无关区域存在主动抑制机制。线索诱导的阿尔法侧化幅度与背侧前扣带回皮层和背外侧前额叶皮层的BOLD呈正相关，这表明执行控制在注意中发挥作用。这些结果表明，IPS和额叶执行区域是对任务相关视觉皮层产生偏向影响的主要来源，而在视觉注意期间，任务无关的默认模式网络和感觉运动皮层会受到抑制。
