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bioRxiv · 10.1101/2024.03.15.585182

Cycle-frequency content EEG analysis improves the assessment of respiratory-related cortical activity

Navarro-Sune, X.·Raux, M.·Hudson, A. L.·Similowski, T.·Chavez, M.
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Abstract

Time-Frequency (T-F) analysis of EEG is a common technique to characterise spectral changes in neural activity. This study explores the limitations of utilizing conventional spectral techniques in examining cyclic event-related cortical activities due to challenges, including high inter-trial variability. Introducing the Cycle-Frequency (C-F) analysis, we aim to enhance the evaluation of cycle-locked respiratory events. For synthetic EEG that mimicked cycle-locked pre-motor activity, C-F had more accurate frequency and time localization compared to conventional T-F analysis, even for a significantly reduced number of trials and a variability of breathing rhythm. Preliminary validations using real EEG data during both unloaded breathing and loaded breathing (that evokes pre-motor activity) suggest potential benefits of using the C-F method, particularly in normalizing time units to cyclic activity phases and refining baseline placement and duration. The proposed approach could provide new insights for the study of rhythmic neural activities, complementing T-F analysis.

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Navarro-Sune, X., Raux, M., Hudson, A. L., Similowski, T., Chavez, M.. 2024-03-17. Cycle-frequency content EEG analysis improves the assessment of respiratory-related cortical activity. https://doi.org/10.1101/2024.03.15.585182

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