Sheng Jintao, Zhang Liang, Liu Chuqi, Liu Jing, Feng Junjiao, Zhou Yu, Hu Huinan, Xue Gui
State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing 100875, China.
Sci Adv. 2022 Apr 22;8(16):eabm3829. doi: 10.1126/sciadv.abm3829. Epub 2022 Apr 20.
Episodic memory enables humans to encode and later vividly retrieve information about our rich experiences, yet the neural representations that support this mental capacity are poorly understood. Using a large fMRI dataset ( = 468) of face-name associative memory tasks and principal component analysis to examine neural representational dimensionality (RD), we found that the human brain maintained a high-dimensional representation of faces through hierarchical representation within and beyond the face-selective regions. Critically, greater RD was associated with better subsequent memory performance both within and across participants, and this association was specific to episodic memory but not general cognitive abilities. Furthermore, the frontoparietal activities could suppress the shared low-dimensional fluctuations and reduce the correlations of local neural responses, resulting in greater RD. RD was not associated with the degree of item-specific pattern similarity, and it made complementary contributions to episodic memory. These results provide a mechanistic understanding of the role of RD in supporting accurate episodic memory.
情景记忆使人类能够编码并随后生动地检索有关我们丰富经历的信息，然而，支持这种心理能力的神经表征却鲜为人知。我们使用一个关于面孔-名字联想记忆任务的大型功能磁共振成像数据集（ = 468）以及主成分分析来研究神经表征维度（RD），发现人类大脑通过面孔选择性区域内外的层次表征，对面孔保持高维表征。至关重要的是，更大的RD与参与者内部和之间更好的后续记忆表现相关，并且这种关联特定于情景记忆而非一般认知能力。此外，额顶叶活动可以抑制共享的低维波动并降低局部神经反应的相关性，从而导致更大的RD。RD与特定项目模式相似性的程度无关，并且它对情景记忆做出了互补贡献。这些结果为RD在支持准确情景记忆中的作用提供了一种机制性理解。
