Instantaneous brain states have consequences for our sensation, perception, and behaviour. Fluctuations in arousal and neural desynchronization likely pose perceptually relevant states. However, their relationship and their relative impact on perception is unclear. We here show that, at the single-trial level in humans, local desynchronization in sensory cortex (expressed as time-series entropy) versus pupil-linked arousal differentially impact perceptual processing. While we recorded electroencephalography (EEG) and pupillometry data, stimuli of a demanding auditory discrimination task were presented into states of high or low desynchronization of auditory cortex via a real-time closed-loop setup. Desynchronization and arousal distinctly influenced stimulus-evoked activity and shaped behaviour displaying an inverted u-shaped relationship: States of intermediate desynchronization elicited minimal response bias and fastest responses, while states of intermediate arousal gave rise to highest response sensitivity. Our results speak to a model in which independent states of local desynchronization and global arousal jointly optimise sensory processing and performance.
EEG data and pupillometry data are publicly available on the Open Science Framework (OSF) https://osf.io/f9kzs/. Custom computer code to reproduce all essential findings are publicly available on the OSF https://osf.io/f9kzs/
Rest EEG recordings in healthy subjects during wakefulness, sleep and anesthesia with ketamine, propofol, and xenonZenodo, 10.5281/zenodo.806176.
- Jonas Obleser
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: Participants gave written informed consent to participate and consent to publish the recorded data in anonymised form. They were financially compensated.The study was approved by the local ethics committee of the University of Lübeck (reference number 15-313) and all experimental procedures were carried out in accordance with the registered protocol.
- Jonathan Erik Peelle, Washington University in St. Louis, United States
© 2019, 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.