Modality-specific tracking of attention and sensory statistics in the human electrophysiological spectral exponent
- MPI for Human Development, Germany
- University of California, San Diego, United States
- Eriksholm Research Centre, Oticon A/S, Denmark
- Max Planck Institute for Human Development, Germany
- University of Lübeck, Germany
Abstract
A hallmark of electrophysiological brain activity is its 1/f-like spectrum - power decreases with increasing frequency. The steepness of this 'roll-off' is approximated by the spectral exponent, which in invasively recorded neural populations reflects the balance of excitatory to inhibitory neural activity (E:I balance). Here, we first establish that the spectral exponent of non-invasive electroencephalography (EEG) recordings is highly sensitive to general (i.e., anaesthesia-driven) changes in E:I balance. Building on the EEG spectral exponent as a viable marker of E:I, we then demonstrate its sensitivity to the focus of selective attention in an EEG experiment during which participants detected targets in simultaneous audio-visual noise. In addition to these endogenous changes in E:I balance, EEG spectral exponents over auditory and visual sensory cortices also tracked auditory and visual stimulus spectral exponents, respectively. Individuals' degree of this selective stimulus-brain coupling in spectral exponents predicted behavioural performance. Our results highlight the rich information contained in 1/f-like neural activity, providing a window into diverse neural processes previously thought to be inaccessible in non-invasive human recordings.
Data availability
Data and code have been deposited on OSF (https://osf.io/wyzrg/).
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (Emmy Noether Programme)
- Leonhard Waschke
- Douglas D Garrett
H2020 European Research Council (ERC-CoG-2014-646696)
- Jonas Obleser
Max Planck UCL Centre for Computational Psychiatry and Ageing Research
- Leonhard Waschke
- Douglas D Garrett
Whitehall Foundation (2017-12-73)
- Bradley Voytek
National Science Foundation (BCS-1736028)
- Bradley Voytek
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: All participants gave written informed consent, reported normalhearing and had normal or corrected to normal vision. All experimental procedures wereapproved by the institutional review board of the University of California, San Diego, Human Research Protections Program (UCSD IRB Protocol #150834. ).
Copyright
© 2021, Waschke et al.
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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Modality-specific tracking of attention and sensory statistics in the human electrophysiological spectral exponent
eLife 10:e70068.
https://doi.org/10.7554/eLife.70068
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