St Jacques Peggy L, Szpunar Karl K, Schacter Daniel L
School of Psychology, University of Sussex, Pevensey 1, Room 2C5, Brighton BN1 9QH, UK.
Department of Psychology, University of Illinois at Chicago, Chicago 60607, USA.
Neuroimage. 2017 Mar 1;148:103-114. doi: 10.1016/j.neuroimage.2016.12.028. Epub 2016 Dec 15.
The dynamic and flexible nature of memories is evident in our ability to adopt multiple visual perspectives. Although autobiographical memories are typically encoded from the visual perspective of our own eyes they can be retrieved from the perspective of an observer looking at our self. Here, we examined the neural mechanisms of shifting visual perspective during long-term memory retrieval and its influence on online and subsequent memories using functional magnetic resonance imaging (fMRI). Participants generated specific autobiographical memories from the last five years and rated their visual perspective. In a separate fMRI session, they were asked to retrieve the memories across three repetitions while maintaining the same visual perspective as their initial rating or by shifting to an alternative perspective. Visual perspective shifting during autobiographical memory retrieval was supported by a linear decrease in neural recruitment across repetitions in the posterior parietal cortices. Additional analyses revealed that the precuneus, in particular, contributed to both online and subsequent changes in the phenomenology of memories. Our findings show that flexibly shifting egocentric perspective during autobiographical memory retrieval is supported by the precuneus, and suggest that this manipulation of mental imagery during retrieval has consequences for how memories are retrieved and later remembered.
记忆的动态和灵活特性在我们采用多种视觉视角的能力中显而易见。尽管自传体记忆通常是从我们自己眼睛的视觉视角进行编码的，但它们可以从观察者看着我们自己的视角被检索出来。在这里，我们使用功能磁共振成像（fMRI）研究了长期记忆检索过程中视觉视角转换的神经机制及其对在线记忆和后续记忆的影响。参与者生成了过去五年中的特定自传体记忆并对他们的视觉视角进行了评分。在一个单独的fMRI实验环节中，他们被要求在保持与初始评分相同的视觉视角或转换到另一个视角的情况下，对这些记忆进行三次重复检索。自传体记忆检索过程中的视觉视角转换得到了后顶叶皮层重复过程中神经活动线性减少的支持。进一步的分析表明，尤其是楔前叶，对记忆现象学的在线和后续变化都有贡献。我们的研究结果表明，自传体记忆检索过程中灵活地转换自我中心视角得到了楔前叶的支持，并表明检索过程中这种心理意象的操作对记忆的检索方式和随后的记忆方式有影响。
