Abstract
Complex behavior entails a balance between taking in sensory information from the environment and utilizing previously learned internal information. Studies on mice show that the brain continually alternates between outward and inward cognitive modes every few seconds, accompanied by stereotyped cascades of neuronal spiking. Our analysis of large fMRI datasets revealed a similar mechanism in humans. Human brain activity was punctuated every several seconds by coherent, propagating waves emerging in the exteroceptive sensorimotor regions and terminating in the interoceptive default mode network. As in mice, these waves in human fMRI are accompanied by phase-specific enhancements in sensory information encoding and memory retrieval. These findings suggest a conserved feature of mammalian brain physiology that bears directly on the integration of sensory and mnemonic information during everyday behavior.
Data availability
For mice single neuron analysis, we used the Neuropixels Visual Coding Neuropixels and two-photon calcium imaging datasets from the Allen Institute32,33, accessible at https://portal.brain-map.org/overview. For resting-state human fMRI analysis, we used HCP-7T dataset from https://www.humanconnectome.org. We shared our EEG-fMRI dataset at https://openneuro.org/datasets/ds003768. For task human fMRI analysis, we used NSD dataset available at https://naturalscenesdataset.org. Source data are provided with this paper. The processed data in this study is available upon request.
Code availability
The Python code that produced the major results of this paper is available at https://github.com/psu-mcnl/fMRI-Arousal. All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials.
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Acknowledgements
This work was supported by the Brain Initiative award (1RF1MH123247-01 to X.L.), the NIH R01 award (1R01NS113889-01A1 to X.L.), the Intramural Research Program of the National Institute of Mental Health (ZIA-MH002838 to D.A.L.), and the Intramural Research Program of the National Institute of Neurological Disorders and Stroke (ZIA-NS003027 to J.H.D.). The authors of this work recognize the Penn State Institute for Computational and Data Sciences (RRID:SCR_025154) for providing access to computational research infrastructure within the Roar Core Facility (RRID: SCR_026424)].
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Conceptualization: Y.Y., X.L. Methodology: Y.Y., X.L. Investigation: Y.Y., X.L. Supervision: X.L. Writing—original draft: Y.Y., D.A.L., J.H.D., and X.L. Writing—review and editing: Y.Y., J.H.D., and X.L.
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Yang, Y., Leopold, D.A., Duyn, J.H. et al. Sensory encoding and memory retrieval are coordinated with propagating waves in the human brain. Nat Commun (2026). https://doi.org/10.1038/s41467-026-69068-x
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DOI: https://doi.org/10.1038/s41467-026-69068-x
