Mendelsohn Avi, Furman Orit, Dudai Yadin
Department of Neurobiology, Weizmann Institute of Science Rehovot, Israel.
Front Behav Neurosci. 2010 Apr 19;4:18. doi: 10.3389/fnbeh.2010.00018. eCollection 2010.
Are specific distributed coactivations in the brain during memory retrieval a signature of retrieval outcome? Here we show that this is indeed the case. Widespread brain networks were reported to be involved in the retrieval of long-term episodic memories. Although functional coactivation among particular regions occurs during episodic memory retrieval, it is unknown to what extent it contributes to the accuracy and confidence of recollection. In this study we set out to explore this question. Participants saw a narrative documentary movie. A week later they underwent an fMRI scan during which they either accepted or rejected factual or fictitious verbal statements concerning the movie. Correct vs. incorrect responses to factual statements were more common and were provided with higher confidence than those made to fictitious statements. Whereas activity in the retrieval network correlated mostly with confidence, coactivations primarily correlated with memory accuracy. Specifically, coactivations of left medial temporal lobe regions with temporal and parietal cortices were greater during correct responses to factual statements, but did not differ between responses to fictitious statements. We propose that network coactivations play a role in recovering memory traces that are relevant to online retrieval cues, culminating in distinct retrieval outcomes.
记忆提取过程中大脑特定的分布式共激活是提取结果的一个标志吗？在这里我们表明情况确实如此。据报道，广泛的脑网络参与长期情景记忆的提取。尽管在情景记忆提取过程中特定区域之间会发生功能共激活，但尚不清楚它在多大程度上有助于回忆的准确性和可信度。在本研究中，我们着手探讨这个问题。参与者观看了一部叙事纪录片电影。一周后，他们接受了功能磁共振成像扫描，在此期间，他们要么接受要么拒绝关于该电影的事实性或虚构的言语陈述。对事实性陈述的正确与错误反应比虚构陈述的反应更常见，且信心更高。虽然提取网络中的活动主要与信心相关，但共激活主要与记忆准确性相关。具体而言，在对事实性陈述的正确反应过程中，左内侧颞叶区域与颞叶和顶叶皮质的共激活更强，但对虚构陈述的反应之间没有差异。我们认为网络共激活在恢复与在线提取线索相关的记忆痕迹中发挥作用，最终导致不同的提取结果。
