记忆编码和提取中的神经激活模式再现

Pattern reinstatement during memory encoding and retrieval

情景记忆使得人们可以在头脑中生动地经历已经发生过的事件,然而支持这一过程的神经机制还没有得到很好地理解.本文针对近年来基于神经激活模式分析的研究对"神经激活模式再现"的假说进行了整合分析,提供了重要的支持性证据.这些研究发现,成功地提取伴随着编码时神经激活模式的再现,且再现的发生先于行为判断出现;除此以外,神经激活重现可以在重复学习过程中发生,或者由相似的学习材料引发,且这种再现程度与随后的记忆效果相关;此外,神经激活模式再现还可以在睡眠和休息条件下自发地产生,促进随后的记忆成绩.在此基础之上,本研究还进一步考察了神经激活模式的本质特征,探讨了内侧颞叶和额顶皮层等重要脑区在再现过程中的作用,并对神经激活模式再现的研究方向进行了展望.

Episodic memory enables humans to vividly re-experience past events via mental time travel. Asproposed by most theoretical and computational models, successful retrieval is accompanied by reinstatement ofrepresentation during encoding. The current study focused on multiple voxel pattern analysis summarizesevidence supporting this hypothesis. It was found that successful retrieval was companied by category and item-specific neural pattern reinstatement. Neural pattern reinstatement could also be triggered by repeated studiesof the same item or similar items, and the degree of reinstatement was associated with subsequent memoryperformance. Spontaneous reinstatement was found both in sleep and during rest when no attention was paid,this reinstatement was also associated with late memory. Base on these observations, we also examined thenature of neural pattern reinstatement and the role of frontal cortex and hippocampus in this process. Finally,we suggest possible ways to further study pattern reinstatement.