Spatiotemporal brain hierarchies of auditory memory recognition and predictive coding - Nature Communications

The full analysis pipeline used in this study is available at the following link: https://doi.org/10.5281/zenodo.11072410 Additional in-house-built code and functions used in this study are part of the LBPD repository which is available at the following link: https://doi.org/10.5281/zenodo.10701724 Abstract Our brain is constantly extracting, predicting, and recognising key spatiotemporal features of the physical world in order to survive. While neural processing of visuospatial patterns has been extensively studied, the hierarchical brain mechanisms underlying conscious recognition of auditory sequences and the associated prediction errors remain elusive. Using magnetoencephalography (MEG), we describe the brain functioning of 83 participants during recognition of previously memorised musical sequences and systematic variations. The results show feedforward connections originating from auditory cortices, and extending to the hippocampus, anterior cingulate gyrus, and medial cingulate gyrus. Simultaneously, we observe backward connections operating in the opposite direction. Throughout the sequences, the hippocampus and cingulate gyrus maintain the same hierarchical level, except for the final tone, where the cingulate gyrus assumes the top position within the hierarchy. The evoked responses of memorised sequences and variations engage the same hierarchical brain network but systematically differ in terms of temporal dynamics, strength, and polarity. Furthermore, induced-response analysis shows that alpha and beta power is stronger for the variations, while gamma power is enhanced for the memorised sequences. This study expands on the predictive coding theory by providing quantitative evidence of hierarchical brain mechanisms during conscious memory and predictive processing of auditory sequences. The data is provided after pre-processing (Maxfilter, ICA for removing eye blink and heart beat, co-registration with the individual MRI T1) and epoching. Source data files are provided for Supplementary Figures and Tables (referred to as Supplementary Data in the paper). Supplementary Figures are provided in PDF format in high resolution.本研究使用的完整分析流程可通过以下链接获取：https://doi.org/10.5281/zenodo.11072410 本研究中使用的额外自研代码与函数隶属于LBPD仓库，获取链接为：https://doi.org/10.5281/zenodo.10701724 摘要 为保障生存，人类大脑始终持续提取、预测并识别物理世界的关键时空特征。尽管针对视觉空间模式的神经加工机制已得到广泛研究，但听觉序列有意识识别背后的层级脑机制及其伴随的预测误差仍未明晰。本研究借助脑磁图（magnetoencephalography, MEG）技术，分析了83名参与者在识别先前记忆的音乐序列及其系统性变体时的脑活动模式。结果显示，存在源自听觉皮层并延伸至海马体、前扣带回皮层与内侧扣带回皮层的前馈连接；同时观察到反向运作的反馈连接。在整个序列加工过程中，海马体与扣带回皮层维持相同的层级地位，仅在最后一个音调处，扣带回皮层跃居层级顶端。记忆序列与变体所激活的诱发电响应共享同一套层级脑网络，但在时间动力学特性、响应强度与极性上存在系统性差异。此外，非锁时诱发响应分析表明，变体的α与β频段功率更强，而记忆序列的γ频段功率则得到增强。本研究为层级脑机制在听觉序列的有意识记忆与预测加工过程中的运作提供了量化证据，拓展了预测编码理论的研究范畴。 本研究提供的数据已完成预处理（包括Maxfilter、用于去除眼电与心电伪迹的独立成分分析（Independent Component Analysis, ICA）、与个体磁共振T1影像的共配准）以及试次分段处理。 补充图表对应的源数据文件（论文中称为补充数据）已一并提供。 补充图片以高分辨率PDF格式提供。