Top-Down and Bottom-Up Attention to Memory Are Dissociated in Posterior Parietal Cortex: Neuroimaging and Neuropsychological Evidence
Top-Down and Bottom-Up Attention to Memory Are Dissociated in Posterior Parietal Cortex: Neuroimaging and Neuropsychological Evidence
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DOI：
10.1523/jneurosci.1209-09.2010
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发表时间：
2010-04-07
影响因子：
5.3
通讯作者：
Moscovitch, Morris
中科院分区：
文献类型：
--
作者：
Ciaramelli, Elisa;Grady, Cheryl;Moscovitch, Morris
后顶叶皮层在情景记忆检索过程中很活跃，但其作用仍不清楚。根据最近的一项提议，背侧顶叶皮层（DPC）将自上而下的注意力分配给记忆检索，而腹侧顶叶皮层（VPC）则通过检索内容介导自下而上的注意力捕获，即注意力记忆（AtoM）假设。在这里，首次将功能磁共振成像（fMRI）和病变技术结合在一项研究中，以测试顶叶皮层在情景检索中的作用。参与者研究单词对，然后在新单词中检测所研究的（目标）单词。在某些情况下，所研究的单词会提示即将出现的目标单词，从而促进识别性能。与 AtoM 假设一致，当参与者根据相关记忆线索搜索/预期记忆目标并预测随后的行为优势时，左 DPC 就会参与其中。相比之下，左 VPC 可以预测非提示试验中目标检测的功效和速度，并且对于无效提示的记忆目标来说效果和速度最大。与 fMRI 证据一致，DPC 病变的患者没有从记忆提示中受益，而 VPC 病变的患者在识别意外的记忆目标方面存在问题。这些结果支持 AtoM 假设，即 DPC 和 VPC 分别介导自上而下和自下而上的记忆检索注意力。
Posterior parietal cortex is active during episodic memory retrieval, yet its role remains unclear. According to a recent proposal, dorsal parietal cortex (DPC) allocates top-down attention to memory retrieval, whereas ventral parietal cortex (VPC) mediates the bottom-up attentional capture by retrieved contents, i.e., the Attention-to-Memory (AtoM) hypothesis. Here, for the first time, functional magnetic resonance imaging (fMRI) and lesion techniques were combined in a single study to test the role of parietal cortex in episodic retrieval. Participants studied word pairs and then detected studied (target) words among new words. In some conditions, a studied word cued the upcoming target word, facilitating recognition performance. In line with the AtoM hypothesis, left DPC was engaged when participants searched for/anticipated memory targets upon presentation of relevant memory cues and predicted the ensuing behavioral advantage. In contrast, left VPC predicted efficacy and speed of target detection on noncued trials and was largest for memory targets that were invalidly cued. Consistent with fMRI evidence, patients with lesions in DPC did not benefit from memory cueing, whereas patients with lesions in VPC had problems recognizing unexpected memory targets. These results support the AtoM hypothesis that DPC and VPC mediate top-down and bottom-up attention to memory retrieval, respectively.