2240 Multimodal imaging of selective recollection in youth and ageing

记忆研究中一个长期存在的问题是人们如何以及何时能够控制他们回忆的内容。例如，你可能想记住上个月和谁喝了一杯远离社交的啤酒，而不想回忆啤酒本身的细节。在回忆的时候，大脑的海马体被认为触发了原始事件中出现的相同皮层模式的恢复。这种恢复被认为是记忆过去的有意识体验的基础。人们可以选择事件的哪些方面被恢复（记忆前控制），还是选择过程在稍后对从记忆中恢复的信息进行操作（记忆后控制）？当记忆前或记忆后的控制能力（或两者都有）受损时，这些能力是如何随着年龄的增长而变化的？人类功能磁共振（fMRI）脑成像已被用于测量恢复，与混合证据选择性回忆。但是功能磁共振成像的时间分辨率很低，所以不能完全区分早期和晚期的认知过程。最近，动态恢复措施已经成为可能，使用脑电图（EEG），它能够更好地区分记忆前和记忆后的控制。潜在影响：了解选择性回忆是如何实现的，对于测试记忆的理论模型，以及提高对记忆受损群体（如健康老年人）的记忆困难的理解至关重要。使用方法：本项目将调查在何种条件下，检索前和检索后的控制可以在年轻人和老年人中实现选择性回忆。学生将学习并应用两种互补的脑成像模式和先进的多变量分析技术，以及为检查记忆控制阶段而开发的记忆任务。您将使用解剖学上精确的功能磁共振成像检查海马体和皮层在选择性回忆中的作用，并使用时间分辨脑电图成像评估选择性记忆表征的动态出现。

A longstanding question in memory research is how and when people are able to control what they recall.For instance, you may want to remember who you had a socially-distanced beer with last month, without recalling details about the beer itself. At the time of recollection the brain's hippocampus is thought to trigger the reinstatement of the same cortical patterns that were present during the original events. This reinstatement is thought to underpin the conscious experience of remembering the past. Can people select which aspects of events are reinstated (preretrieval control), or do selective processes operate later on the information recovered from memory (postretrieval control)? And how do these abilities change as people age when preretrieval or postretrieval control (or both) may be impaired? Human functional magnetic resonance (fMRI) brain imaging has been used to measure reinstatement, with mixed evidence for selective recollection. But fMRI has very low time resolution so cannot fully separate early from late cognitive processes. More recently, dynamic measures of reinstatement have become possible using electroencephalography (EEG), which is better able to distinguish preretrieval from postretrieval control of recollection. POTENTIAL IMPACT: Understanding how selective recollection is achieved is essential for testing theoretical models of memory, and improving understanding of memory difficulties in groups with impaired recollection like healthy older people. APPROACHES TO BE USED: This project will investigate the conditions under which preretrieval and postretrieval control can achieve selective recollection in younger and older adults. The student will learn and apply two complementary brain imaging modalities with advanced multivariate analysis techniques, alongside memory tasks developed to examine stages of memory control. You will examine the roles of the hippocampus and cortex in selective recollection using anatomically precise fMRI, and assess the dynamic emergence of selective memory representations with time-resolved EEG imaging.