High-order brain interactions in ketamine during rest and task: a double-blinded cross-over design using portable EEG on male participants

作者：Rubén Herzog, Florentine Barbey, Md Nurul Islam, Laura M. Rueda‐Delgado, Hugh Nolan, Pavel Prado, Marina Krylova, Igor Izyurov, Nooshin Javaheripour, Lena Vera Danyeli, Zümrüt Duygu Şen, Martin Walter, Patricio O’Donnell, Derek L. Buhl, Brian Murphy, Agustín Ibáñez · 发表于：Translational Psychiatry · 年份：2024 · DOI：10.1038/s41398-024-03029-0 · 被引用次数：14 · 研究领域：Functional Brain Connectivity Studies、Treatment of Major Depression、Neural dynamics and brain function

Ketamine is a dissociative anesthetic that induces a shift in global consciousness states and related brain dynamics. Portable low-density EEG systems could be used to monitor these effects. However, previous evidence is almost null and lacks adequate methods to address global dynamics with a small number of electrodes. This study delves into brain high-order interactions (HOI) to explore the effects of ketamine using portable EEG. In a double-blinded cross-over design, 30 male adults (mean age = 25.57, SD = 3.74) were administered racemic ketamine and compared against saline infusion as a control. Both task-driven (auditory oddball paradigm) and resting-state EEG were recorded. HOI were computed using advanced multivariate information theory tools, allowing us to quantify nonlinear statistical dependencies between all possible electrode combinations. Ketamine induced an increase in redundancy in brain dynamics (copies of the same information that can be retrieved from 3 or more electrodes), most significantly in the alpha frequency band. Redundancy was more evident during resting state, associated with a shift in conscious states towards more dissociative tendencies. Furthermore, in the task-driven context (auditory oddball), the impact of ketamine on redundancy was more significant for predictable (standard stimuli) compared to deviant ones. Finally, associations were observed between ketamine's HOI and experiences of derealization. Ketamine appears to increase redundancy a...