Right TPJ deactivation during visual search: Functional significance and support for a filter hypothesis
Right TPJ deactivation during visual search: Functional significance and support for a filter hypothesis
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DOI：
10.1093/cercor/bhl170
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发表时间：
2007-11-01
期刊：
影响因子：
3.7
通讯作者：
Corbetta, Maurizio
中科院分区：
文献类型：
--
作者：
Shulman, Gordon L.;Astafiev, Serguei V.;Corbetta, Maurizio
行为表现取决于关注环境中的重要物体，而不是不相关的物体。在右颞顶叶交界区（TPJ）被认为是参与重新定向注意到新的对象，是行为相关的。当受试者监视一系列干扰物以寻找目标时，TPJ会停用，直到检测到目标。我们已经提出，去激活反映了从TPJ过滤不相关的输入，防止不重要的对象被关注。该假设预测，当检测到后续目标时，对干扰物的平均失活应大于错过的，反映了更有效的过滤。分析血氧水平依赖（BOLD）的任务诱发信号从20名受试者在2个监测任务证实了这一预测的区域在右缘上回（SMG）。由于失活之前的目标，这意味着BOLD检测的关系并没有反映反馈的目标检测或posttetection过程。显示这种关系的SMG区域重叠或重叠了一些与"默认"脑功能模式相关的区域，这表明在任务执行过程中某些默认区域的失活具有功能意义。
Behavioral performance depends on attending to important objects in the environment rather than irrelevant objects. Regions in the right temporal-parietal junction (TPJ) are thought to be involved in redirecting attention to new objects that are behaviorally relevant. When subjects monitor a stream of distracter objects for a target, TPJ deactivates until the target is detected. We have proposed that the deactivation reflects the filtering of irrelevant inputs from TPJ, preventing unimportant objects from being attended. This hypothesis predicts that the mean deactivation to distracters; should be larger when the subsequent target is detected than missed, reflecting more efficient filtering. An analysis of the blood oxygenation level-dependent (BOLD) task-evoked signals from 20 subjects during 2 monitoring tasks confirmed this prediction for regions in right supramarginal gyrus (SMG). Because the deactivation preceded the target, this mean BOLD-detection relationship did not reflect feedback from target detection or posttletection processes. The SMG regions showing this relationship overlapped or neighbored some regions associated with a '' default '' mode of brain function, suggesting the functional significance of deactivations in some default regions during task performance.