Semantic representations in the temporal pole predict false memories
Semantic representations in the temporal pole predict false memories
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DOI：
10.1073/pnas.1610686113
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发表时间：
2016-09-06
影响因子：
11.1
通讯作者：
Hassabis, Demis
中科院分区：
文献类型：
--
作者：
Chadwick, Martin J.;Anjum, Raeesa S.;Hassabis, Demis
神经科学的最新进展使我们对错误记忆的神经机制有了前所未有的了解，表明人工记忆可以以与真实记忆无法区分的方式插入海马体的记忆细胞中。然而，仅此还不足以解释错误记忆如何在我们的日常生活中自然产生。认知心理学已经证明，无论是在实验室还是在现实世界中，许多错误记忆的例子都可以归因于语义干扰。尽管之前的研究发现不同的区域表现出一定程度的语义错误记忆，但没有揭示支撑这一现象的语义表征的本质。在这里，我们使用功能磁共振成像和表征相似性分析来搜索与语义错误记忆一致的神经代码。我们发现了明确的证据，表明错误记忆是由颞极中基于相似性的神经代码产生的，该区域被称为大脑的“语义中心”。我们进一步表明，每个人在颞极内都有部分独特的语义代码，这种独特的代码可以预测记忆错误的特殊模式。最后，我们证明相同的神经代码也可以预测真实记忆性能的变化，这与错误记忆的自适应观点一致。总而言之，我们的发现揭示了语义知识的神经表征的潜在结构，以及这种语义结构如何增强和扭曲我们的记忆。
Recent advances in neuroscience have given us unprecedented insight into the neural mechanisms of false memory, showing that artificial memories can be inserted into the memory cells of the hippocampus in a way that is indistinguishable from true memories. However, this alone is not enough to explain how false memories can arise naturally in the course of our daily lives. Cognitive psychology has demonstrated that many instances of false memory, both in the laboratory and the real world, can be attributed to semantic interference. Whereas previous studies have found that a diverse set of regions show some involvement in semantic false memory, none have revealed the nature of the semantic representations underpinning the phenomenon. Here we use fMRI with representational similarity analysis to search for a neural code consistent with semantic false memory. We find clear evidence that false memories emerge from a similarity-based neural code in the temporal pole, a region that has been called the "semantic hub" of the brain. We further show that each individual has a partially unique semantic code within the temporal pole, and this unique code can predict idiosyncratic patterns of memory errors. Finally, we show that the same neural code can also predict variation in true-memory performance, consistent with an adaptive perspective on false memory. Taken together, our findings reveal the underlying structure of neural representations of semantic knowledge, and how this semantic structure can both enhance and distort our memories.