Brain
April 9, 2013
Winston Chiong, Stephen M. Wilson, Mark D’Esposito et al.
234 citations
Large-scale brain networks coordinate human behavior, and their anatomy helps explain how neurodegenerative diseases progress. Alzheimer's disease targets the default mode network, while behavioral variant frontotemporal dementia targets the salience network. The default mode network is active when healthy people consider personal moral dilemmas, yet Alzheimer's patients respond normally to these dilemmas, whereas frontotemporal dementia patients give abnormally utilitarian responses. This discrepancy may arise because the salience network modulates default mode network activity.
Proc Natl Acad Sci U S A
February 1, 2022
Daniel Toker, Ioannis Pappas, Janna D. Lendner et al.
148 citations
During conscious states, the cortex operates near a mathematically specific critical point called the edge-of-chaos, the boundary between stability and chaos. Applying a modified 0-1 chaos test to ECoG and MEG recordings from humans and macaques, evidence suggests that unconscious states—such as generalized seizure and anesthesia—involve a shift of low-frequency cortical oscillations away from this critical point, disrupting information processing. Psychedelic states tune these oscillations closer to the critical point, potentially increasing information richness. Analysis of clinical EEG from patients with disorders of consciousness indicates that measuring proximity to this critical point may serve as a clinical index of consciousness.
bioRxiv
June 11, 2021
Daniel Toker, Ioannis Pappas, Janna D. Lendner et al.
3 citations
preprint
During conscious states, the cortex's electrical activity operates near the edge-of-chaos critical point—the boundary between stability and chaos. Applying a new chaos test to ECoG and MEG recordings from humans and macaques across waking, seizure, anesthesia, and psychedelic states shows that unconsciousness shifts cortical dynamics away from this critical point, disrupting information processing. Psychedelics may enhance information-richness by tuning activity closer to this point. Analysis of EEG from patients with disorders of consciousness suggests that measuring proximity to the edge-of-chaos critical point could serve as a clinical biomarker of consciousness.