[en] Mind blanking (MB) is a waking state during which we do not report any mental content. The phenomenology of MB challenges the view of a constantly thinking mind. Here, we comprehensively characterize the MB’s neurobehavioral profile with the aim to delineate its role during ongoing mentation. Using functional MRI experience sampling, we show that the reportability of MB is less frequent, faster, and with lower transitional dynamics than other mental states, pointing to its role as a transient mental relay. Regarding its neural underpinnings, we observed higher global signal amplitude during MB reports, indicating a distinct physiological state. Using the time-varying functional connectome, we show that MB reports can be classified with high accuracy, suggesting that MB has a unique neural composition. Indeed, a pattern of global positive-phase coherence shows the highest similarity to the connectivity patterns associated with MB reports. We interpret this pattern’s rigid signal architecture as hindering content reportability due to the brain’s inability to differentiate signals in an informative way. Collectively, we show that MB has a unique neurobehavioral profile, indicating that nonreportable mental events can happen during wakefulness. Our results add to the characterization of spontaneous mentation and pave the way for more mechanistic investigations of MB’s phenomenology.
Funding text :
This work was supported by the Belgian Fund for Scientific Research (FNRS). S. Mortaheb is a research fellow, A. Demertzi is a research associate, and S. Majerus is a research director at the FNRS. We also thank Dr. Matthieu Koroma, Dr. Camilo Miguel Signorelli, and Mr. Larry D. Fort for proofreading and editing the manuscript. This article is based upon work from COST Action CA18106, supported by COST (European Cooperation in Science and Technology).
Preprocessed functional data at the level of ROI time series can be freely downloaded from: https://osf.io/ 3vqb6/download. The raw data are also freely available in BIDS format from: https://openneuro.org/datasets/ds004134/versions/1.0.0. All the preprocessing and analysis codes are freely available on GitLab: https://gitlab.uliege.be/S.Mortaheb/mind_blanking.