Parietal and Frontal Cortex Encode Stimulus-Specific Mnemonic Representations during Visual Working Memory.
Parietal and Frontal Cortex Encode Stimulus-Specific Mnemonic Representations during Visual Working Memory.
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DOI：
10.1016/j.neuron.2015.07.013
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发表时间：
2015-08-19
期刊：
影响因子：
16.2
通讯作者：
Serences JT
中科院分区：
文献类型：
--
作者：
Ester EF;Sprague TC;Serences JT
工作记忆（Working memory， WM）使人们能够在活动状态下对信息进行存储和操作。长期以来，WM存储与额叶和顶叶皮层区域网络的持续激活增加有关。然而，最近的证据表明，这些区域主要编码与一般任务目标相关的信息，而不是特定记忆的特征选择表征。这些与目标相关的表征被认为提供了自上而下的反馈，协调了早期感觉区域中细粒度细节的表征。在这里，我们使用基于fmri的区域级激活模式的记忆视觉细节重建来测试该模型。我们可以根据枕部视觉皮层和额叶和顶叶皮层的几个子区域的激活模式重建高保真的记忆方向表征，而不依赖于平均激活的持续增加。这些结果挑战了假设不连接的额顶叶“自上而下控制”和后感觉“特征存储”网络的WM模型。
Working memory (WM) enables the storage and manipulation of information in an active state. WM storage has long been associated with sustained increases in activation across a network of frontal and parietal cortical regions. However, recent evidence suggests that these regions primarily encode information related to general task goals rather than feature-selective representations of specific memoranda. These goal-related representations are thought to provide top-down feedback that coordinates the representation of fine-grained details in early sensory areas. Here, we test this model using fMRI-based reconstructions of remembered visual details from region-level activation patterns. We could reconstruct high-fidelity representations of a remembered orientation based on activation patterns in occipital visual cortex and in several sub-regions of frontal and parietal cortex, independent of sustained increases in mean activation. These results challenge models of WM that postulate disjoint frontoparietal “top-down control” and posterior sensory “feature storage” networks.