PLoS Computational Biology
April 14, 2015
Joon-Young Moon, UnCheol Lee, Stefanie Blain‐moraes et al.
143 citations
Efficient brain networks balance global integration with functional specialization, but how global topology, local node dynamics, and information flow relate has been unclear. Using analytical solutions of oscillator models, computational simulations on model and anatomical brain networks, and high-density electroencephalography from conscious and anesthetized humans, the authors demonstrate that network nodes with more connections (higher degree) have larger amplitudes and are directional targets (phase lag) rather than sources (phase lead). This degree–directionality relationship appears to be a fundamental network property with direct applicability to brain function. Changes in directionality patterns across states of human consciousness are driven by alterations in brain network topology.
Frontiers in Human Neuroscience
March 18, 2021
Emma R. Huels, Hyoungkyu Kim, UnCheol Lee et al.
51 citations
Shamanic practitioners in trance show brain changes that overlap with but are distinct from those caused by psychedelic drugs. In 24 practitioners and 24 controls, EEG recordings during shamanic drumming revealed increased gamma power linked to visual changes, decreased low alpha and increased low beta connectivity, reduced gamma-band signal diversity tied to insightfulness, and increased criticality in beta and gamma bands correlating with complex imagery. Practitioners' altered-state scores matched or exceeded those of people on psychedelics. The findings indicate that shamanic trance and psychedelic states share some phenomenal features but produce unique neural signatures.
Scientific Reports
February 16, 2021
Catherine Duclos, Danielle Nadin, Yacine Mahdid et al.
28 citations
Three-node network motifs—recurring patterns of connections—reorganize in the brain during anesthetic-induced unconsciousness and recovery. In nine healthy volunteers undergoing a 3-hour anesthesia protocol, electroencephalography (EEG) recordings in the alpha band (8–13 Hz) showed that two specific motifs (motifs 1 and 5) changed their topology significantly between responsive and unresponsive states. Motif 1 consisted of long-range chain-like connections, while motif 5 comprised short-range loop-like connections. The topological reorganization of motif 5 preceded the return of responsiveness, and motif 1 accompanied it, suggesting these motifs may help reveal neural correlates of consciousness.