Cortical encoding of acoustic and linguistic rhythms in spoken narratives
Abstract
Speech contains rich acoustic and linguistic information. Using highly controlled speech materials, previous studies have demonstrated that cortical activity is synchronous to the rhythms of perceived linguistic units, e.g., words and phrases, on top of basic acoustic features, e.g., the speech envelope. When listening to natural speech, it remains unclear, however, how cortical activity jointly encodes acoustic and linguistic information. Here, we investigate the neural encoding of words using electroencephalography, and observe neural activity synchronous to multi-syllabic words when participants naturally listen to narratives. An amplitude modulation (AM) cue for word rhythm enhances the word-level response, but the effect is only observed during passive listening. Furthermore, words and the AM cue are encoded by spatially separable neural responses that are differentially modulated by attention. These results suggest that bottom-up acoustic cues and top-down linguistic knowledge separately contribute to cortical encoding of linguistic units in spoken narratives.
Data availability
The EEG data and analysis code (in MatLab) were uploaded as Source data files.
Article and author information
Author details
Funding
National Natural Science Foundation of China (31771248)
- Nai Ding
Major Scientific Research Project of Zhejiang Lab (2019KB0AC02)
- Nai Ding
National Key R & D Program of China (2019YFC0118200)
- Nai Ding
Zhejiang Provincial Natural Science Foundation of China (LGF19H090020)
- Cheng Luo
Fundamental Research Funds for the Central Universities (2020FZZX001-05)
- Nai Ding
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: The experimental procedures were approved by the Research Ethics Committee of the College of Medicine, Zhejiang University (2019-047). All participants provided written informed consent prior to the experiment and were paid.
Copyright
© 2020, Luo & Ding
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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