The number of attentional foci and their precision are dissociated in the posterior parietal cortex.
The number of attentional foci and their precision are dissociated in the posterior parietal cortex.
复制标题
注意焦点的数量及其精确度在后顶叶皮层中是分离的。
DOI：
10.1093/cercor/bhp197
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
Jiang,YV
中科院分区：
文献类型：
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作者：
Shim,WonMok;Alvarez,GA;Vickery,TJ;Jiang,YV
许多日常任务都需要我们集中注意力追踪移动的物体。当跟踪的目标越多，移动速度越快时，对注意力的需求就会增加。注意的这两个方面——为目标分配多个注意焦点（或指数）和精确监控每个焦点——可能涉及不同的认知和大脑机制。在这项研究中，我们使用功能性磁共振成像来量化背侧注意区域对注意焦点数量及其时空精度变化的响应谱。受试者被要求追踪一个或两个以不同速度旋转的风车的特定辐条。当被跟踪的风车越多，被跟踪的风车旋转得越快时，他们的跟踪性能就会下降。然而，只有当受试者追踪更多的风车时，后顶叶活动才会增加，而当他们追踪更快的风车时，后顶叶活动保持不变。当有更多的目标和目标旋转更快时，前额视野和早期视觉区域的活动增加。这些结果表明，后顶叶皮层专门参与索引独立的运动目标的注意力，而不是精确地监测每个焦点。
Many everyday tasks require us to track moving objects with attention. The demand for attention increases both when more targets are tracked and when the targets move faster. These 2 aspects of attention—assigning multiple attentional foci (or indices) to targets and monitoring each focus with precision—may tap into different cognitive and brain mechanisms. In this study, we used functional magnetic resonance imaging to quantify the response profile of dorsal attentional areas to variations in the number of attentional foci and their spatiotemporal precision. Subjects were asked to track a specific spoke of either 1 or 2 pinwheels that rotated at various speeds. Their tracking performance declined both when more pinwheels were tracked and when the tracked pinwheels rotated faster. However, posterior parietal activity increased only when subjects tracked more pinwheels but remained flat when they tracked faster moving pinwheels. The frontal eye fields and early visual areas increased activity when there were more targets and when the targets rotated faster. These results suggest that the posterior parietal cortex is specifically involved in indexing independently moving targets with attention but not in monitoring each focus with precision.