Brain network motifs are markers of loss and recovery of consciousness
Catherine Duclos, Danielle Nadin, Yacine Mahdid, Vijay Tarnal, Paul Picton, Giancarlo Vanini, Goodarz Golmirzaie, Ellen Janke, Michael S. Avidan, Max B. Kelz, George A. Mashour, Stefanie Blain‐moraes
Scientific Reports February 16, 2021 DOI: 10.1038/s41598-021-83482-9 via OpenAlex
Summary
AI-generated from the abstractThree-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.
Study at a glance
| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 9 |
| Population | Healthy human subjects |
| Duration | 3-hour anesthetic protocol; epochs extracted at Baseline, Induction, Unconscious, 30-, 10-, 5-min pre-recovery, and 30- and 180-min post-recovery |
| Keywords | Motif music Unconsciousness Electroencephalography Topology electrical circuits Neuroscience |
| Citations | 28 |
| Key finding | Topological reorganization of 3-node network motifs (motifs 1 and 5) in the alpha band accompanies anesthetic-induced loss and recovery of consciousness. |
Abstract
Motifs are patterns of inter-connections between nodes of a network, and have been investigated as building blocks of directed networks. This study explored the re-organization of 3-node motifs during loss and recovery of consciousness. Nine healthy subjects underwent a 3-h anesthetic protocol while 128-channel electroencephalography (EEG) was recorded. In the alpha (8-13 Hz) band, 5-min epochs of EEG were extracted for: Baseline; Induction; Unconscious; 30-, 10- and 5-min pre-recovery of responsiveness; 30- and 180-min post-recovery of responsiveness. We constructed a functional brain network using the weighted and directed phase lag index, on which we calculated the frequency and topology of 3-node motifs. Three motifs (motifs 1, 2 and 5) were significantly present across participants and epochs, when compared to random networks (p < 0.05). The topology of motifs 1 and 5 changed significantly between responsive and unresponsive epochs (p-values < 0.01; Kendall's W = 0.664 (motif 1) and 0.529 (motif 5)). Motif 1 was constituted of long-range chain-like connections, while motif 5 was constituted of short-range, loop-like connections. Our results suggest that anesthetic-induced unconsciousness is associated with a topological re-organization of network motifs. As motif topological re-organization may precede (motif 5) or accompany (motif 1) the return of responsiveness, motifs could contribute to the understanding of the neural correlates of consciousness.