Constructive episodic simulation of the future and the past: Distinct subsystems of a core brain network mediate imagining and remembering
Constructive episodic simulation of the future and the past: Distinct subsystems of a core brain network mediate imagining and remembering
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DOI：
10.1016/j.neuropsychologia.2008.10.026
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发表时间：
2009-09-01
期刊：
影响因子：
2.6
通讯作者：
Schacter, Daniel L.
中科院分区：
文献类型：
--
作者：
Addis, Donna Rose;Pan, Ling;Schacter, Daniel L.
最近的神经成像研究表明，记忆过去和想象未来依赖于同一个核心大脑网络。然而，在记忆和想象事件过程中的共同核心网络活动以及在未来事件模拟过程中的活动增加可以反映过去事件作为未来事件的重铸。我们通过实验重新组合参与者自己过去经历的事件细节，从而防止将过去的事件重铸为想象中的事件。此外，我们指示参与者想象未来和过去的事件，以消除在以前的研究中发现的未来事件特定活动是专门与展望有关，还是与想象情景事件的一般需求有关。使用时空部分最小二乘（PLS），结合对比证实，即使受试者被要求将细节重新组合成想象的事件（并阻止重新投射事件），在整个核心网络中，记忆和想象事件之间的显著神经重叠是明显的。然而，PLS分析确定了核心网络中的两个子系统。一个广泛的子系统优先与想象未来和过去的事件相关联。这一发现表明，先前与未来事件相关的区域，如前海马体、内侧前额叶皮层和额下回，支持的是想象事件的一般过程，而不是前瞻性的特定过程。PLS分析还确定了一个子系统，包括海马体、海马体旁回和后视皮层的广泛区域，这些子系统在记忆丰富的背景和视觉空间细节的过去事件时优先参与。(C) 2008 Elsevier Ltd版权所有。
Recent neuroimaging studies demonstrate that remembering the past and imagining the future rely on the same core brain network. However, findings of common core network activity during remembering and imagining events and increased activity during future event simulation could reflect the recasting of past events as future events. We experimentally recombined event details from participants' own past experiences, thus preventing the recasting of past events as imagined events. Moreover, we instructed participants to imagine both future and past events in order to disambiguate whether future-event-specific activity found in previous studies is related specifically to prospection or a general demand of imagining episodic events. Using spatiotemporal partial-least-squares (PLS), a conjunction contrast confirmed that even when subjects are required to recombine details into imagined events (and prevented from recasting events), significant neural overlap between remembering and imagining events is evident throughout the core network. However, the PLS analysis identified two subsystems within the core network. One extensive subsystem was preferentially associated with imagining both future and past events. This finding suggests that regions previously associated with future events, such as anterior hippocampus, medial prefrontal cortex and inferior frontal gyrus, support processes general to imagining events rather than specific to prospection. This PLS analysis also identified a subsystem, including hippocampus, parahippocampal gyrus and extensive regions of posterior visual cortex that was preferentially engaged when remembering past events rich in contextual and visuospatial detail. (C) 2008 Elsevier Ltd. All rights reserved.