Wang Liting, Liu Huan, Zhang Xin, Zhao Shijie, Guo Lei, Han Junwei, Hu Xintao
School of Automation, Northwestern Polytechnical University, Xi'an, China.
Institute of Medical Research, Northwestern Polytechnical University, Xi'an, China.
Front Neurosci. 2022 Mar 24;16:843988. doi: 10.3389/fnins.2022.843988. eCollection 2022.
By integrating hierarchical feature modeling of auditory information using deep neural networks (DNNs), recent functional magnetic resonance imaging (fMRI) encoding studies have revealed the hierarchical neural auditory representation in the superior temporal gyrus (STG). Most of these studies adopted supervised DNNs (e.g., for audio classification) to derive the hierarchical feature representation of external auditory stimuli. One possible limitation is that the extracted features could be biased toward discriminative features while ignoring general attributes shared by auditory information in multiple categories. Consequently, the hierarchy of neural acoustic processing revealed by the encoding model might be biased toward classification. In this study, we explored the hierarchical neural auditory representation an fMRI encoding framework in which an unsupervised deep convolutional auto-encoder (DCAE) model was adopted to derive the hierarchical feature representations of the stimuli (naturalistic auditory excerpts in different categories) in fMRI acquisition. The experimental results showed that the neural representation of hierarchical auditory features is not limited to previously reported STG, but also involves the bilateral insula, ventral visual cortex, and thalamus. The current study may provide complementary evidence to understand the hierarchical auditory processing in the human brain.
通过使用深度神经网络（DNN）整合听觉信息的分层特征建模，最近的功能磁共振成像（fMRI）编码研究揭示了颞上回（STG）中的分层神经听觉表征。这些研究大多采用监督式DNN（例如用于音频分类）来推导外部听觉刺激的分层特征表征。一个可能的局限性是，提取的特征可能偏向于判别性特征，而忽略了多个类别中听觉信息共有的一般属性。因此，编码模型揭示的神经声学处理层次可能偏向于分类。在本研究中，我们探索了一种fMRI编码框架中的分层神经听觉表征，其中采用无监督深度卷积自动编码器（DCAE）模型来推导fMRI采集过程中刺激（不同类别的自然听觉摘录）的分层特征表征。实验结果表明，分层听觉特征的神经表征不仅限于先前报道的STG，还涉及双侧脑岛、腹侧视觉皮层和丘脑。当前的研究可能为理解人类大脑中的分层听觉处理提供补充证据。
