情绪记忆早期改变在阿尔茨海默病进程中的作用、影响因素及神经调节通路研究

Nowadays, studies have focused their attention on cognitive decline caused by AD and the mechanism of injury. However, little was concerned on the preserved ability of the disease especially in the incipient stage, such as preserved emotional perception, preserved emotional expression and preserved emotional enhancement of memory (EEM). Our previous research also verify that MCI patients still have positive EEM effects. However, the impact factors and neural mechanisms are mainly unknown. Thus, we speculate that the positive emotion modulation and positive EEM effect are preserved during the early stage of AD, and those preservation may due to the preserved functions of positive emotion related brain areas, which further promoting the behaviors of memory; or due to some neural compensatory mechanisms. This project is going to focus on the relationships between emotion and memory with the help of multimodal MR techniques. The purposes of this study are to explore the factors that may affect emotional memory and EEM effect during the encoding, consolidation or retrieval process, and to explore how the emotion modulate on memory, the compensatory mechanism of neural modulation, and the dynamic changes during normal aging and the course of Alzheimer's disease. This project would provide theoretical foundations for new methods of recovery training with the help of stimulative effects mediated by emotion on memory. And to make the precise treatment possible by taking the neural modulation pathway of emotional memory into account. It will bring out not only the scientific and clinical significance, but also huge society benefits.

目前对阿尔茨海默病（AD）的研究多集中在认知功能损伤及其机制，而对病情早期尚保留的正确辨识情绪、正确表达情绪，情绪的记忆增强效应等，尚缺乏系统细致的研究。我们前期研究已证实轻度认知障碍（MCI）患者仍存在正性情绪增强效应，但其影响因素及神经机制尚不完全明确。故推测痴呆早期正性情绪调控仍存在，并对记忆有增强作用，该作用或与疾病早期调控正性情绪的脑区功能尚保留，进而促进记忆；或者与存在一些神经代偿机制有关。本项目拟利用多模态MR技术，研究正常老化和痴呆进程中情绪与记忆之间的关系，编码、固化、提取过程中情绪记忆和情绪增强效应的影响因素，情绪对记忆的神经调节机制和神经代偿机制，及其动态变化，为后期临床利用情绪对记忆的促进作用，开拓记忆康复训练治疗新方法、并进一步利用情绪记忆神经调节通路进行精准干预治疗提供理论依据，具有重要的科学意义及重大社会效益。

情绪对记忆存在增强效应（EEM），但在阿尔茨海默病和正常老化进程中EEM的影响因素及其神经机制目前尚不明确。本研究联合情绪记忆行为学和多模态MRI影像数据，从脑结构、功能、网络等层面多维度探索，发现情绪记忆受到唤醒度、愉悦度、提取方式的共同影响；aMCI患者保留高唤醒图片的EEM效应，且存在性别差异，情绪记忆网络存在一定程度的代偿；AD患者则完全失去了EEM效应，其机制可能与AD情绪记忆功能网络向规则化网络转变，重要节点的功能改变，及半球内与半球间的神经连接环路均受损有关；而正常老化过程中情绪记忆与年轻组表现相似，情绪记忆网络的功能及情绪记忆相关重要脑区的灰质体积相对保留。此外与正常老化组比较，aMCI患者“记起”过程的再认分辨力下降，但“熟悉”过程的再认分辨力未见变化，而AD患者“记起”与“熟悉”过程中的再认分辨力均受损，提示“记起”通道可能比“熟悉”通道更易在AD疾病过程中受损。我们的研究揭示了AD进程和正常老化过程中情绪记忆的改变情况及其可能的神经机制，为后期临床利用情绪对记忆的促进作用对患者进行干预以提高其记忆水平，提供了潜在的线索和理论依据；结合情绪记忆行为学和影像学表现有助于AD的早期诊断。