Proposed EEG measures of consciousness: a systematic, comparative review

In the past few decades, a large number of time-series-based EEG measures of consciousness have been proposed, motivated by diverse theoretical frameworks ranging from global workspace theory to integrated information theory and the entropic brain hypothesis. This systematic review aimed to survey all such measures and compare their behaviour across different states of consciousness (wakefulness, sleep, anaesthesia, psychedelics).

The review covered over 5,000 articles (most screened and excluded), and yielded a comparative dataset of measures across conditions. While the review did not produce major surprises, the results show that most measures behave similarly across states and, critically, that the field likely does not require additional novel metrics. The manuscript received positive peer review but was ultimately declined due to being approximately one year out of date at first rejection, and nearly two years by the final round of reviews. An update is in progress.

Despite its preprint status, the data and findings are freely available and have been cited by subsequent work. The project represents one of the most substantial individual undertakings of the PhD, and the extracted information from the reviewed articles continues to inform ongoing research.

Contributions: Responsible for analysis and manuscript; co-responsible for acquisition and interpretation.

Recommended citation: Nilsen, A. S., Juel, B. E., Thürer, B., & Storm, J. F. (2020). Proposed EEG measures of consciousness: a systematic, comparative review. PsyArXiv.
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