Department of Psychology, Washington University in St. Louis, St. Louis, Missouri 63130, USA.
J Neurosci. 2010 Feb 24;30(8):2924-34. doi: 10.1523/JNEUROSCI.4225-09.2010.
Functional neuroimaging studies of episodic recognition demonstrate an increased lateral parietal response for studied versus new materials, often termed a retrieval success effect. Using a novel memory analog of attentional cueing, we manipulated the correspondence between anticipated and actual recognition evidence by presenting valid or invalid anticipatory cues (e.g., "likely old") before recognition judgments. Although a superior parietal region demonstrated the retrieval success pattern, a larger inferior parietal lobule (IPL) region tracked the validity of the memory cueing (invalid cueing > valid cueing) and no retrieval success-sensitive lateral parietal region was insensitive to cueing. The invalid cueing response occurred even for correctly identified new items unlikely to trigger substantive episodic retrieval. Within the IPL, although supramarginal and angular gyrus (SMG; AG) regions both demonstrated invalid cueing amplitude elevations, each region differentially coupled with distinct cortical networks when unexpectedly old items were encountered; a connectivity pattern also observed at rest in the same subjects. These findings jointly suggest that the lateral parietal response during recognition does not signify the recovery of episodic content, but is a marker of the violation of memory expectations. A second independent dataset confirmed this interpretation by demonstrating that SMG activation tracked the decision biases of observers, not their accuracy, with increased activation for nondominant recognition judgments. The expectancy violation interpretation of the lateral parietal recognition response is consistent with the literature on visual search and oddball paradigms and suggests that damage to these regions should impair memory-linked orienting behavior and not retrieval per se.
情景记忆识别的功能神经影像学研究表明，与新的材料相比，被研究的材料会引起侧顶叶反应增强，这种反应通常被称为检索成功效应。我们使用一种新的注意线索记忆模拟方法，通过在识别判断之前呈现有效或无效的预期线索（例如，“很可能是旧的”），来操纵预期和实际识别证据之间的一致性。尽管上顶叶区域表现出检索成功模式，但更大的下顶叶区域（IPL）区域则跟踪记忆线索的有效性（无效线索＞有效线索），并且没有检索成功敏感的侧顶叶区域对线索不敏感。即使对于不太可能引发实质性情景检索的正确识别的新项，无效线索反应也会发生。在 IPL 内，尽管缘上回和角回（SMG；AG）区域都表现出无效线索幅度升高，但当遇到意外的旧项时，每个区域都与不同的皮质网络不同地耦合；在同一受试者中，这种连接模式在静息状态下也观察到。这些发现共同表明，识别过程中的侧顶叶反应并不表示情景内容的恢复，而是记忆预期被违反的标志。第二个独立数据集通过证明 SMG 激活跟踪观察者的决策偏差，而不是他们的准确性，来证实了这一解释，即对于非主导识别判断，激活增加。侧顶叶识别反应的期望违反解释与视觉搜索和异常范式的文献一致，并表明这些区域的损伤应该会损害与记忆相关的定向行为，而不是检索本身。
