Wang Min, Yu Banglei, Luo Cimei, Fogelson Noa, Zhang Junjun, Jin Zhenlan, Li Ling
Key Laboratory for NeuroInformation of Ministry of Education, High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, Center for Information in Medicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China; Bioinformatics and BioMedical Bigdata Mining Laboratory, School of Big Health, Guizhou Medical University, China.
Key Laboratory for NeuroInformation of Ministry of Education, High-Field Magnetic Resonance Brain Imaging Key Laboratory of Sichuan Province, Center for Information in Medicine, School of Life Science and Technology, University of Electronic Science and Technology of China, Chengdu, China.
Cortex. 2020 May;126:200-212. doi: 10.1016/j.cortex.2020.01.005. Epub 2020 Feb 12.
Previous studies demonstrate that frontal and parietal cortices are involved in bottom-up and top-down attentional processes. However, their respective contribution to these processes remains controversial. The purpose of the current study was to compare the causal contribution of frontal and parietal cortices to the control of bottom-up and top-down visual attention using functional magnetic resonance imaging (fMRI) and repetitive transcranial magnetic stimulation (rTMS). Subjects performed visual search for targets that were easy (pop-out) or difficult (non-pop-out) to distinguish from distractors. Three sites of interest were used, based on the individual fMRI activation during the performance of a search task: the right dorsolateral prefrontal cortex (rDLPFC), the right frontal eye field (rFEF) and the right superior parietal lobule (rSPL). Online rTMS stimulation, with the search onset, showed that relative to rTMS over the vertex, rTMS over the rDLPFC, the rFEF and the rSPL increased the search reaction time (RTs) in the non-pop-out condition. In comparison, no TMS effect was found in the pop-out condition. In addition, the search RT cost caused by the non-pop-out condition was larger after the rDLPFC-TMS compared to the vertex-TMS. The findings suggest that the frontal and parietal cortical regions are both involved in attentional processing during top-down visual search, and that the rDLPFC is causally related to the executive control of cognitive load increases between the pop-out and the non-pop-out search.
先前的研究表明，额叶和顶叶皮质参与自下而上和自上而下的注意力过程。然而，它们对这些过程的各自贡献仍存在争议。本研究的目的是使用功能磁共振成像（fMRI）和重复经颅磁刺激（rTMS）比较额叶和顶叶皮质对自下而上和自上而下视觉注意力控制的因果贡献。受试者对容易（突出）或难以（不突出）与干扰物区分的目标进行视觉搜索。基于搜索任务执行期间的个体fMRI激活，使用了三个感兴趣的部位：右侧背外侧前额叶皮质（rDLPFC）、右侧额叶眼区（rFEF）和右侧顶上小叶（rSPL）。在搜索开始时进行的在线rTMS刺激表明，相对于头顶的rTMS，rDLPFC、rFEF和rSPL上的rTMS在不突出条件下增加了搜索反应时间（RTs）。相比之下，在突出条件下未发现TMS效应。此外，与头顶TMS相比，rDLPFC-TMS后不突出条件导致的搜索RT成本更大。研究结果表明，额叶和顶叶皮质区域在自上而下的视觉搜索过程中都参与了注意力处理，并且rDLPFC与突出和不突出搜索之间认知负荷增加的执行控制存在因果关系。
