Beijing Key Laboratory of Learning and Cognition and Department of Psychology, Capital Normal University, Beijing 100048, China; Center for Brain and Cognition Sciences and Department of Psychology, Peking University, Beijing 100871, China.
Department of Psychology, LMU München, D-80802 München, Germany.
Neuroimage. 2011 Jul 1;57(1):235-241. doi: 10.1016/j.neuroimage.2011.04.024. Epub 2011 Apr 22.
The fMRI technique was used to investigate the functional neuroanatomy of binding features within- or cross-dimension during visual conjunction search. Participants were asked to perform feature search (FS; e.g., search for a vertical bar among tilted bars), within-dimension search (WS; e.g., search for an upright T among non-target oriented Ts and Ls), cross-dimension search (CS; e.g., search for an orange vertical bar among blue vertical bars and orange tilted bars), and complex search combining within- and cross-dimension features (WCS; e.g., search for an orange upright T among orange leftward Ts and blue Ls). Reaction times (RTs) taken to decide whether a target was present or absent were faster in the FS than in the WS, CS, and WCS conditions, but did not differ between the latter three conditions. Neuroimaging results revealed a set of fronto-parietal regions, including frontal eye field and intraparietal sulcus, to be consistently activated in conjunction search (WS, CS, and WCS) relative to feature search, suggesting that these regions play a more prominent role in matching visual input against the target template in conjunction search. Furthermore, left occipito-temporal cortex was more activated in within-dimension conjunction search, and bilateral intraparietal sulci were more activated in cross-dimension conjunction search. This suggests that features from the same dimension are 'bound' at a higher stage of the ventral pathway by conjoining the inputs from lower-level neurons, whereas neurons along the intraparietal sulcus appear to be necessary for discerning the presence of cross-dimensional conjunctions.
功能性磁共振成像（fMRI）技术被用于研究在视觉联合搜索中跨维度或同维度内绑定特征的功能神经解剖学。要求参与者进行特征搜索（FS；例如，在倾斜的棒中搜索垂直棒）、同维度搜索（WS；例如，在非目标定向的 T 和 L 中搜索垂直 T）、跨维度搜索（CS；例如，在蓝色垂直棒和橙色倾斜棒中搜索橙色垂直棒）以及结合同维度和跨维度特征的复杂搜索（WCS；例如，在橙色向左的 T 和蓝色 L 中搜索橙色垂直 T）。决定目标是否存在的反应时间（RT）在 FS 中比在 WS、CS 和 WCS 条件下更快，但后三种条件之间没有差异。神经影像学结果显示，一组额顶叶区域，包括额眼区和顶内沟，在联合搜索（WS、CS 和 WCS）中相对于特征搜索始终被激活，这表明这些区域在匹配视觉输入和目标模板方面发挥了更重要的作用联合搜索。此外，左枕颞叶皮层在同维度联合搜索中更活跃，双侧顶内沟在跨维度联合搜索中更活跃。这表明来自同一维度的特征通过结合来自较低层次神经元的输入在腹侧通路的更高阶段被“绑定”，而沿顶内沟的神经元似乎对于辨别跨维度联合是必要的。
