Madore Kevin P, Szpunar Karl K, Addis Donna Rose, Schacter Daniel L
Department of Psychology and Center for Brain Science, Harvard University, Cambridge, MA 02138;
Department of Psychology, University of Illinois at Chicago, Chicago, IL 60607;
Proc Natl Acad Sci U S A. 2016 Sep 20;113(38):10696-701. doi: 10.1073/pnas.1612278113. Epub 2016 Sep 6.
Recent behavioral work suggests that an episodic specificity induction-brief training in recollecting the details of a past experience-enhances performance on subsequent tasks that rely on episodic retrieval, including imagining future experiences, solving open-ended problems, and thinking creatively. Despite these far-reaching behavioral effects, nothing is known about the neural processes impacted by an episodic specificity induction. Related neuroimaging work has linked episodic retrieval with a core network of brain regions that supports imagining future experiences. We tested the hypothesis that key structures in this network are influenced by the specificity induction. Participants received the specificity induction or one of two control inductions and then generated future events and semantic object comparisons during fMRI scanning. After receiving the specificity induction compared with the control, participants exhibited significantly more activity in several core network regions during the construction of imagined events over object comparisons, including the left anterior hippocampus, right inferior parietal lobule, right posterior cingulate cortex, and right ventral precuneus. Induction-related differences in the episodic detail of imagined events significantly modulated induction-related differences in the construction of imagined events in the left anterior hippocampus and right inferior parietal lobule. Resting-state functional connectivity analyses with hippocampal and inferior parietal lobule seed regions and the rest of the brain also revealed significantly stronger core network coupling following the specificity induction compared with the control. These findings provide evidence that an episodic specificity induction selectively targets episodic processes that are commonly linked to key core network regions, including the hippocampus.
近期的行为学研究表明，情景特异性诱导——即对过去经历细节进行回忆的简短训练——能提高后续依赖情景检索任务的表现，包括想象未来经历、解决开放式问题和创造性思考。尽管有这些深远的行为学影响，但对于情景特异性诱导所影响的神经过程却一无所知。相关的神经影像学研究已将情景检索与支持想象未来经历的核心脑区网络联系起来。我们检验了这样一个假设，即该网络中的关键结构会受到特异性诱导的影响。参与者接受特异性诱导或两种对照诱导之一，然后在功能磁共振成像（fMRI）扫描过程中生成未来事件并进行语义对象比较。与对照相比，接受特异性诱导后，参与者在想象事件构建过程中，相对于对象比较，在几个核心网络区域表现出显著更多的活动，这些区域包括左侧前海马体、右侧顶下小叶、右侧后扣带回皮质和右侧腹侧楔前叶。想象事件的情景细节中与诱导相关的差异显著调节了左侧前海马体和右侧顶下小叶在想象事件构建中与诱导相关的差异。对海马体和顶下小叶种子区域与大脑其他部分进行静息态功能连接分析也显示，与对照相比，特异性诱导后核心网络耦合显著增强。这些发现提供了证据，表明情景特异性诱导选择性地针对通常与包括海马体在内的关键核心网络区域相关联的情景过程。
