情绪唤醒影响联结记忆的制约因素及认知神经机制

As an important kind of episodic memory, associative memory will bind together disparate elements of an experience into an integrated representation, which takes a very great role on enlarging memory capacity, facilitating memory productivity and forming complicated memory and has significant implications for understanding associative memory impairment from aging, schizophrenia, post traumatic stress disorder and dysmnesia, etc. Meanwhile, It has been debated how emotional arousal affects associative memory. Many studies have confirmed that emotional arousal can enhance associative memory; however, there are inconsistent results that found emotional arousal can impair associative memory. Therefore, it is very valued to explore cognitive and neural correlates of effect of emotional arousal on associative memory. In recent years, a lot of research had explored that emotional arousal’s facilitation or impairment on item memory, however, few research focused on the limits and cognitive neural mechanisms of effect of emotional arousal on associative memory. ..In 5 studies, with item-context picture as experimental materials and with cued association recognition paradigm as experimental methods, through behavioral data, eye movement and event-related potentials, the present proposal aims to: 1）find and wholly discuss the factors which limit emotional arousal’s impairing effects on associative memory; 2) test the unitized hypothesis through manipulating the pattern and degree in which item and context are linked together, based on dissociation of the role of emotional arousal from the role of attention; 3) investigate the controlled process and automatic process embedded in effect of emotional arousal on associative memory in encoding phase and retrieve phase, to explain the cognitive and neural mechanisms of effect of emotional arousal on associative memory.

联结记忆是情景记忆的一种重要形式，对扩大记忆数量，提高记忆效率以及形成复杂的记忆都有极大的影响，而情绪唤醒会削弱或者增强联结记忆。因此，对情绪唤醒影响联结记忆的制约因素及认知神经机制的探索不仅有助于我们深入认识情绪与记忆的关系问题，也有助于我们更好地理解认知老化、精神分裂、创伤后应激障碍及记忆障碍等人群的联结记忆受损。近年来，针对单个项目的记忆研究已经探讨了情绪唤醒对记忆的促进和损害作用，但我国关于情绪唤醒影响联结记忆的研究还刚刚开始。本项目从情绪唤醒影响项目-背景联结记忆的角度入手，利用行为实验、眼动和ERP技术，试图：1）发现并系统分析对情绪唤醒影响联结记忆产生制约作用的因素；2）在对注意的作用和情绪唤醒的影响加以分离的基础上，从项目-背景的联系方式与程度方面检验一体化假设的适用范围；3）揭示情绪唤醒影响联结记忆的意识参与程度和时间进程，以更深入地探讨情绪唤醒影响联结记忆的认知神经机制

针对单个项目的记忆研究已经证实，情绪唤醒对记忆会产生促进或损害作用，而情绪唤醒对联结记忆的影响近年来才受到国内外研究者的关注，还是一个崭新的研究领域。本项目使用行为实验、眼动和ERP技术，力图深入探讨情绪唤醒影响联结记忆的制约因素及其认知神经机制。在本项目的研究过程中，项目组开展了如下工作：1.以项目-背景组成的复合图片为实验材料，考察了情绪唤醒对项目-背景或联结记忆的影响是否会受到项目特性，背景特性，以及项目-背景之间的联系方式和联结程度的制约。研究发现当项目特性和背景特性均显著，且项目与背景具有紧密的语义和空间联系时，情绪唤醒对项目-背景联结记忆的削弱作用会受到抑制。2.通过操纵情绪特性(效价、唤醒、情绪一致性)，材料属性(材料复杂性以及联结捆绑数量)以及记忆的不同加工阶段(编码，巩固)考察了情绪唤醒对联结记忆影响的认知机制。研究发现注意并不能完全解释情绪唤醒对联结记忆的影响，情绪唤醒对联结记忆的影响还会受到情绪本身的特性，联结捆绑的材料特性以及不同记忆加工阶段的调节。3.使用ERP技术，探讨了情绪唤醒与编码方式对联结记忆的影响，以及情绪唤醒影响联结记忆的时间进程。研究发现，有意编码能够促进联结记忆一体化表征的形成，且情绪唤醒对联结记忆的影响主要发生在刺激呈现阶段。这些研究成果的发现，为更好地理解情绪唤醒对联结记忆的影响提供了坚实的理论基础。