The hippocampus remains activated over the long term for the retrieval of truly episodic memories.
The hippocampus remains activated over the long term for the retrieval of truly episodic memories.
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DOI：
10.1371/journal.pone.0043495
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发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Rauchs G
中科院分区：
文献类型：
--
作者：
Harand C;Bertran F;La Joie R;Landeau B;Mézenge F;Desgranges B;Peigneux P;Eustache F;Rauchs G
海马体在陈述性记忆巩固中的作用是一个激烈争论的问题。本研究利用功能性磁共振成像（fMRI）研究了近距离和远距离信息记忆提取的神经机制。18名年轻健康的参与者学习了一系列图片。然后，在3天和3个月后的两次fMRI识别过程中，他们必须使用“记住/知道”程序来确定他们是否认出了每一张图片。在两个延迟中呈现相同的学习图像，使我们能够跟踪记忆的演变，并将那些最初是情景记忆的记忆与那些随着时间的推移变得熟悉或语义化的记忆区分开来，并且在没有任何上下文细节的情况下检索。随着时间的推移，海马激活最初的情节，后来的语义记忆，但保持稳定的一贯情节的，至少在其后部。对于这两种类型的记忆，新皮层激活观察到在两个延迟，特别是在腹内侧前额叶和前扣带皮层。这些激活可能反映了神经网络内记忆痕迹的逐渐重组。我们的数据表明，随着时间的推移，海马和皮质-皮质连接在情景记忆的巩固和恢复中的维持和加强，与多痕迹理论（Nadel和Moscovitch，1997）一致。不同的是，随着时间的推移，通过加强皮质-皮质连接和海马体的逐渐脱离，记忆变得语义化。
The role of the hippocampus in declarative memory consolidation is a matter of intense debate. We investigated the neural substrates of memory retrieval for recent and remote information using functional magnetic resonance imaging (fMRI). 18 young, healthy participants learned a series of pictures. Then, during two fMRI recognition sessions, 3 days and 3 months later, they had to determine whether they recognized or not each picture using the “Remember/Know” procedure. Presentation of the same learned images at both delays allowed us to track the evolution of memories and distinguish consistently episodic memories from those that were initially episodic and then became familiar or semantic over time and were retrieved without any contextual detail. Hippocampal activation decreased over time for initially episodic, later semantic memories, but remained stable for consistently episodic ones, at least in its posterior part. For both types of memories, neocortical activations were observed at both delays, notably in the ventromedial prefrontal and anterior cingulate cortices. These activations may reflect a gradual reorganization of memory traces within neural networks. Our data indicate maintenance and strengthening of hippocampal and cortico-cortical connections in the consolidation and retrieval of episodic memories over time, in line with the Multiple Trace theory (Nadel and Moscovitch, 1997). At variance, memories becoming semantic over time consolidate through strengthening of cortico-cortical connections and progressive disengagement of the hippocampus.
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影响因子：
25
作者：
Eldridge, LL;Knowlton, BT;Engel, SA
通讯作者：
Engel, SA
影响因子：
2.6
作者：
CERMAK, LS;OCONNOR, M
通讯作者：
OCONNOR, M
DOI：
10.1073/pnas.0705454104
发表时间：
2007-11-20
影响因子：
11.1
作者：
Gais, Steffen;Albouy, Genevieve;Peigneux, Philippe
通讯作者：
Peigneux, Philippe
DOI：
10.1073/pnas.0409848102
发表时间：
2005-02-15
影响因子：
11.1
作者：
Dolcos, F;LaBar, KS;Cabeza, R
通讯作者：
Cabeza, R
影响因子：
3.6
作者：
Bosshardt, S;Schmidt, CF;Henke, K
通讯作者：
Henke, K