Department of Cognitive Psychology, Institute of Psychology, University of Hamburg, 20146 Hamburg, Germany.
Institute of Experimental Psychology, Heinrich Heine University Düsseldorf, Germany.
Cereb Cortex. 2019 Sep 13;29(10):4154-4168. doi: 10.1093/cercor/bhy298.
Updating established memories in light of new information is fundamental for memory to guide future behavior. However, little is known about the brain mechanisms by which existing memories can be updated. Here, we combined functional magnetic resonance imaging and multivariate representational similarity analysis to elucidate the neural mechanisms underlying the updating of consolidated memories. To this end, participants first learned face-city name pairs. Twenty-four hours later, while lying in the MRI scanner, participants were required to update some of these associations, but not others, and to encode entirely new pairs. Updating success was tested again 24 h later. Our results showed increased activity of the dorsolateral prefrontal cortex (dlPFC) specifically during the updating of existing associations that was significantly stronger than when simple retrieval or new encoding was required. The updating-related activity of the dlPFC and its functional connectivity with the hippocampus were directly linked to updating success. Furthermore, neural similarity for updated items was markedly higher in the dlPFC and this increase in dlPFC neural similarity distinguished individuals with high updating performance from those with low updating performance. Together, these findings suggest a key role of the dlPFC, presumably in interaction with the hippocampus, in the updating of established memories.
根据新信息更新已建立的记忆对于记忆引导未来行为至关重要。然而，对于现有记忆如何被更新的大脑机制知之甚少。在这里，我们结合功能磁共振成像和多元表象相似性分析来阐明巩固记忆更新的神经机制。为此，参与者首先学习人脸-城市名称对。24 小时后，当他们躺在磁共振成像扫描仪中时，要求他们更新其中的一些关联，但不更新其他关联，并编码全新的关联。24 小时后再次测试更新的效果。我们的结果表明，背外侧前额叶皮层（dlPFC）在更新现有关联时的活动增加，特别是当需要简单检索或新编码时，这种活动明显更强。dlPFC 的更新相关活动及其与海马体的功能连接与更新成功直接相关。此外，更新项目在 dlPFC 中的神经相似性明显更高，这种 dlPFC 神经相似性的增加将具有高更新表现的个体与低更新表现的个体区分开来。总之，这些发现表明 dlPFC 在巩固记忆的更新中起着关键作用，可能与海马体相互作用。
